Communicable Diseases, Table of Contents
CHAPTER VIII
THE DIARRHEAL GROUP OF DISEASES
The diseases which may be grouped together as inflammationsof the intestinal tract, and which possess in common the symptom diarrhea, wereof much less importance during the World War than during any previous majorconflict of which we have record. It will be the main attempt of this chapter,therefore, to show not only the fact of the greatly decreased incidence of thesediseases as compared to that of earlier wars, but to study the causes of thisdecrease and to deduce, if possible, from this study the lines along whichfurther progress in their prevention may be made.
In the comparison of the rates for the diarrheal diseasesobtaining during the World War with those of earlier wars we are at once facedwith a difficulty arising from differences in nomenclature. The last few decadeshave been so fruitful of discoveries in the pathology and etiology of diseaseand in advances in the exactness of clinical diagnosis that the significance ofmany a diagnostic term as understood to-day is widely different from thataccepted only a short time ago. The modern conception of dysentery is that of aclinical entity or complex characterized by an increase in the number of stools,which contain pus, mucus, and blood, accompanied by abdominal pain and tenesmus.This symptom complex may be induced by several known specific agents, of whichthe most important are the dysentery bacilli and the Entamoba histolytica. Ofthe dysentery bacilli there are several well recognized, more or less nearlyrelated strains, and possibly other bacteria such as the paratyphoid grouporganisms may at times cause the same group of symptoms. Conditions permittingaccurate diagnostic work, the Surgeon General accepts the diagnosis"dysentery" only when supported by evidence as to the specificcausative organism. Under war conditions it usually proved impossible to carryout the laboratory studies necessary to such proof and hence by far the greaternumber of cases of dysentery reported during the war period were unclassifiedetiologically. A minority, however, were reported as of bacillary or amebicorigin. Headings are found in the war tabulations for balantidic dysentery andfor dysentery due to other protozoal agents.
In addition to the dysenteries properly so called, there werereported during the war a large number of cases under the headings"diarrhea," "enteritis," and "colitis," the twolatter combined in the tabulations. It is self-evident on account of theclinical character of these conditions that a certain number of cases recordedas diarrhea or as enterocolitis actually may well have been dysentery, and,conversely, that some of the cases recorded as "dysentery,unclassified" might better have been called diarrhea or enterocolitis had astrict etiological classification been possible. That in general, however, the
aUnless otherwise stated, all figures for the World War period are derived from sick and wounded reports sent to the Surgeon General.-Ed.
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distinction between the dysenteries and the nonspecificdiarrheal diseases is a valid one on clinical grounds there can be no doubt aswill be shown later.
In the earlier records of the United States Army littleattempt seems to have been made to distinguish accurately the different types of"intestinal flux." Diarrhea, dysentery, enteritis, and colitis, aswell as other now archaic diagnostic terms, were used evidently more or lessinterchangeably. In the Medical and Surgical History of the War of theRebellion,1 the "fluxes"are divided into four groups: Acute and chronic diarrhea and acute and chronicdysentery. Modern diagnostic criteria were not sufficiently in use during theperiod of the Spanish-American War and the Philippine insurrection to make thestatistics of that period much more valuable in the differentiation of thevarious types of intestinal disease than were those of earlier years. Indeed, inspite of increased diffusion of knowledge and of greatly increased laboratoryfacilities, experience during the World War has shown that under fieldconditions-and the greater number of these cases must be expected to occurduring active campaigning-accurate differentiation is impossible. For thisreason comparisons between the incidence of diarrheal diseases in the World War,and that in earlier conflicts must necessarily be based on totals of the entiregroup. Nor is this necessarily an unscientific or illogical method of comparisonfor, so far as may be said at present, the methods of transmission of thediseases of this group, varying as they do clinically and etiologically, areessentially the same. We believe that they are all acquired by the ingestion ofinfected food or drinkb and thatconsequently the underlying predisposing causes and the necessary preventivemeasures must be considered to be the same for all these diseases howeverdifferent the specific etiology of individual cases.
Returning to the question of the nomenclature of thesediseases, it is evident that in spite of the probability of some confusion inrecent statistics, and of the impossibility of separating from the statistics ofthe past any groups comparable to those of modern tables, there can be littledoubt that in the statistics of the World War the diarrheal diseases can bedivided into two clinically different groups, on the one hand those which werereported as dysentery on clinical grounds and on the other those cases whichwere perhaps more loosely classified as diarrhea, colitis, or enteritis. Thedistinction between these two groups originally made by the clinicians in theindividual cases is emphasized and confirmed by the study of the incidence ofthe two groups month by month, and by a comparison of the severity of the casesas shown by the average number of days lost from duty per case. Table 47 showsthe monthly incidence rates of these diseases for the white enlisted men on dutyin the United States for the period of the war. Inasmuch as these figures arenot influenced by sharp variations in sanitary conditions such as occurredduring operations at the front in France, they furnish a better means ofcomparing the varying incidence of disease than would the figures for the entireArmy. The rates under the heading "Dysentery (all)" include allspecifically diagnosed cases of dysentery and all cases of "Dysentery,unclassified."
bWith the possible exception of diarrheas believed by some to be due to chilling of the abdomen.
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TABLE 47.-Diarrheal diseases. Primaryadmissions, white enlisted men in the United States,April,1917, to December, 1919. Annual rates per 1,000 by months
|
| Diarrhea | Enteritis | Total |
| Dysentery (all) | Diarrhea | Enteritis | Total |
|
|
|
|
|
| 1919 |
|
|
|
|
April | 1.76 | 2.09 | 17.63 | 21.48 | January | .52 | 2.43 | 4.32 | 7.27 |
May | 1.76 | 2.49 | 17.11 | 21.36 | February | .38 | 1.17 | 4.10 | 5.65 |
June | 2.41 | 4.70 | 23.75 | 30.86 | March | .38 | 1.59 | 4.45 | 6.42 |
July | .63 | 5.44 | 26.88 | 32.95 | April | .35 | 2.19 | 3.85 | 6.39 |
August | .87 | 6.21 | 43.36 | 50.44 | May | .74 | 2.59 | 4.98 | 8.31 |
September | 1.28 | 6.54 | 32.05 | 39.87 | June | .49 | 3.06 | 8.85 | 12.40 |
October | .72 | 4.86 | 17.75 | 23.33 | July | .28 | 4.07 | 10.88 | 15.23 |
November | .64 | 1.04 | 7.76 | 9.44 | August | .23 | 5.43 | 14.85 | 20.51 |
December | .34 | .69 | 6.72 | 7.75 | September | .56 | 3.54 | 9.40 | 13.50 |
| 1918 |
|
|
|
| October | .43 | 5.83 | 6.52 | 12.78 |
January | .36 | 1.20 | 6.75 | 8.31 | November | .54 | 3.17 | 7.52 | 11.23 |
February | .14 | .94 | 6.77 | 7.85 | December | .27 | 2.04 | 8.95 | 11.26 |
March | .50 | 1.20 | 9.76 | 11.46 |
|
|
|
|
|
Average, 1917 | 1.16 | 3.78 | 21.45 | 26.39 | |||||
April | .49 | 3.98 | 13.04 | 17.51 | Average, 1918 | .58 | 5.67 | 11.74 | 17.97 |
May | .79 | 5.28 | 15.62 | 21.69 | Average, 1919 | .46 | 3.09 | 7.39 | 10.94 |
June | 1.17 | 9.78 | 18.70 | 29.65 | Average for war | .64 | 4.89 | 12.92 | 18.45 |
July | .91 | 11.34 | 19.94 | 32.19 |
|
|
|
|
|
August | .69 | 13.66 | 21.69 | 36.04 | |||||
September | .82 | 8.63 | 11.74 | 21.19 | |||||
October | .29 | 4.48 | 6.21 | 10.98 | |||||
November | .36 | 4.67 | 5.47 | 10.50 | |||||
December | .38 | 2.83 | 4.31 | 7.52 |
Study of the figures given in Table 47, and the graphiccomparison of the rates shown in Chart XXXVI, which is drawn from the samefigures on a logarithmic scale of ordinates, leads to the conclusion that whilethe rates for cases classed as "diarrhea" and those for "enterocolitis"rose and fell together in almost perfect correlation, the cases classed as"dysentery" varied independently, showing not nearly so much seasonal variation, and the curve for dysen-
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tery is quite independent of that for diarrhea or that forenterocolitis. We are thus justified on statistical grounds in assuming that thedistinction made by the reporting officers is an entirely valid one. We arefurther supported in this conclusion by the analysis of the severity of theaverage case as shown by the number of days lost from duty per case under eachheading. Three thousand five hundred and forty-seven cases of dysentery in whiteenlisted men accounted for the loss of 99,561 days, or 28.3 days per case. Therewere 19,125 cases classed as "diarrhea," with 215,420 days lost, or11.2 days per case. Enterocolitis resulted in the loss of 605,811 days among56,865 cases, the average case losing 11.4 days from duty. It is seen that thetwo latter conditions were of equal severity, while the dysentery cases averagedmuch greater severity. It seems amply justifiable, therefore, to divide theconsideration of these diseases into two groups, the dysenteries, on the onehand, and the cases reported as "diarrhea" and as "enterocolitis,"on the other. Both groups are doubtless of mixed etiology. In the dysenterygroup we shall find some data for conclusions as to the relative importance ofthe recognized inciting agents in the period of the war. In the second group nospecific statements as to bacterial or protozoal etiology are possible.
Table 47 shows the further interesting fact that the ratesfor all classes of diarrheal diseases showed a marked tendency to decrease astime passed. The highest rates were shown during the first months ofmobilization, during the period of voluntary recruiting, and before thecompletion of the great training camps and cantonments which housed the NationalArmy during the period of preparation. During the following year, 1918, althoughthe camps were constantly filled with recruits as the older troops were sent tothe front, the rates for these diseases showed a definite decline. This mayprobably be best explained by the improved environmental conditions possible inthe completed camps and by the results of training in sanitary matters. However,the rates for 1919 showed a still further improvement. During this year thecamps were the scene of the rapid demobilization of the Army. Men returned fromabroad and passed rapidly to the camp selected for discharge. Conditions werenot as favorable for maintaining a high sanitary standard as was the case in theprevious year, though every effort was made to do so. It may be permissible toargue that the low rates during demobilization indicate that in the intestinalinfections as in those of the respiratory tract the seasoned soldier shows agreater resistance than does the recruit.
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TABLE 48.-The diarrheal diseases (dysentery, acute and chronic, and diarrhea). Admissions and deaths, absolute numbers and ratios per 1,000 per annum, white enlisted men, United States Army, 1819 to 1919
aFor years 1819-1848, inclusive, statistics are for the year ending Sept.30, for the years 1849-1882, inclusive, year ending June 30; for the years1883-1919, inclusive, year ending Dec. 31.
bCholera epidemic, Black Hawk War.
cNo strength records available for these years.
dCovers period of Mexican War (1847-48).
eCivil War period: Ratios per 1,000 per annum for deaths, based on followingstrengths: 1862, 288,919; 1863, 659,955; 1864, 675,412; 1865, 645,506; 1866,101,897; 1867, 40,183.
fYears 1898-1903, inclusive, covers period of Spanish-American War andPhilippine insurrection; also covers period; of the China expedition. (1900-01).
gThese two years (1898-99) not tabulatedseparately; does not include enteritis.
hReported as "other diarrheal diseases," but does not includedysentery and enteritis.
iPrevious to this year, officers were included with white enlisted men;beginning 1904 they are excluded.
j1916 includes enteritis.
kCovers period of World War, through period of demobilization.
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Table 48 and Chart XXXVII, drawn from the same figures on alogarithmic scale of ordinates, show the experience of the United States Armywith diarrheal diseases for the 100-year period 1819-1919. Inasmuch as in theearlier years there were no colored enlisted men in the Army, the figures arefor white enlisted men throughout. The rates are the total of dysentery,diarrhea, enteritis, and colitis, since for the reasons given no accuratedifferentiation of these diseases is possible during this period. While thereare periods for which no figures are available it is evident that there has beena definite downward trend in the rates for admissions and deaths from thesediseases broken only by wars and mobilizations. The figures for the Mexican Warperiod are missing, but reports indicate that the rates for diarrhea anddysentery were excessively high at that time. The additional conclusionfrom these figures is that during the century each war showeda decreasingly great increase in the incidence of the diarrheas over thepreceding peace-time figures. This tendency culminated in the World War, duringwhich the rates for the combined diarrheal diseases were actually lower than atany previous time in the history of our Army.
Some details of this record will be considered later andfurther comparisons made. Here it will suffice to point out that while in therecord of the Civil War a large volume was required for the consideration ofthese diseases, here they occupy but insignificant space. In theSpanish-American War and Philippine insurrection, the dysenteries and diarrheasformed a formidable proportion of the total illnesses afflicting the troops. Itshould be remembered in this connection, however, that these campaigns wereconducted in tropical countries and the special liability to intestinal diseaseof troops serving
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in the Tropics has long been recognized. Doubtless some ofthe freedom from these diseases enjoyed by the Army in the World War was theresult of the geographical location of the territory occupied, but making allallowance for this factor it becomes evident that the disparity in rates fordiarrheal diseases between the World War and those preceding it must be mainlydue to improved methods and practices of sanitation.
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TABLE 49.-Dysentery (all), diarrhea, andenterocolitis. Officers and enlisted men, United States Army, by countries ofoccurrence. Primary admissions, deaths, discharges for disability, andnoneffectiveness, absolute numbers and ratios per 1,000 per annum, April, 1917,to December, 1919
320-321
TABLE 49.-Dysentery(all), diarrhea, and enterocolitis. Officers and enlisted men, United StatesArmy by countries of occurrence. Primary admissions, deaths, discharges fordisability, and noneffectiveness, absolute numbers and ratios per 1,000 perannum, April, 1917, to December, 1919-Continued
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OCCURRENCE IN THE WORLD WAR
A general view of the occurrence of the diarrheal group ofdiseases during the World War is given in Table 49. The figures are not only forthe Army as a whole but also for those fractions stationed in the principalgeographical locations occupied by our troops. The cases are grouped under fourheadings, "Dysentery (all)," which includes the unclassified cases aswell as those etiologically diagnosed, "Diarrhea," and "Enterocolitis,"the latter including cases reported as either enteritis or colitis. The fourthheading gives the total of the three named, thus representing for the World Warperiod a close approximation to the totals given for the preceding century inTable 48. The absolute numbers under each heading are for the period of the war.The corresponding rates per thousand are based on a strength aggregate obtainedby the summation of the mean strength for each year, the resulting rate being anannual rate per thousand strength. In the case of the noneffective rate theannual figure is further divided by 365 to give a rate directly comparable tothe usual average noneffective rate of Army reports, which represents the numberof men per thousand constantly excused from duty for any given cause.
Of the total of 92,512 admissions only 4,738 were reported asdysentery cases, or 5.12 per cent of the group. It is probable, owing to thepolicy of the Surgeon General already referred to, of requiring an etiologicaldiagnosis in reports of cases of dysentery whenever facilities for such work areavailable, that a certain proportion of cases of dysentery were reported underthe other headings as diarrhea, or more probably as enteritis or colitis.However, a most liberal estimate of such cases could not more than double theprobable number of dysentery cases and that would mean that but 10 per cent ofthe diarrheal group of diseases were dysentery. In the Philippines and in Panamathat proportion was exceeded, but there is no reason for extending the effect oftropical environment to the mass of the Army. It would appear, then, that astriking fact in the figures before us is that the proportion of cases of theserious or fatal type, true dysentery, was small compared to the total of thegroup. That the total incidence, while impressive in absolute numbers of cases,was not of serious import in loss of man power, is shown by the annual admission rate of 22.41 per annum, which, distributed over a year, would mean alittle less than two cases per month for each thousand men. As the greaternumber of these admissions were for the milder types of intestinal disturbance,the total number of days lost from duty on account of diseases of this groupamounted to only 1,061,229, a figure that gives a noneffective rate for theperiod of 0.71, which means that on the average 1 man in a little over 1,400 wasexcused from duty on account of one of these conditions.
The loss to the Army by deaths due to this group totaled 267,with an annual rate per thousand of 0.07, or 1 death per year in each 14,282men. An even smaller number of men were lost to the service by discharge fordisability, namely, 243, which gives a rate of 0.05 per thousand per annum, or 1each year to 20,000 men.
As a measure of the progress made in military sanitation inthe last half century it is instructive to compare the record given above withthat of the Civil War. There were during that conflict 1,585,196 cases ofdiarrhea and dysentery
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in an average strength of 2,193,427 white troops.1 Had thesame rate prevailed in the World War there would have been 2,601,915 cases amongwhite troops. Had the incidence rate for colored troops in the Civil Warobtained in the World War there would likewise have been 240,517 cases among ourcolored soldiers, a total of 2,842,432. As a matter of fact there were reportedas diarrhea and dysentery during the World War but 27,171 cases, or less than 1per cent of the number that would have obtained had Civil War conditions beenrepeated. If we include the enterocolitis cases reported during the World Warthe total, already given, is 92,512, or, roughly, 3 per cent of the cases tohave been expected at Civil War rates.
In the Civil War there were 37,794 deaths among white troopsand 6,764 among colored troops charged to dysentery and diarrhea. At these ratesthere would have been 62,021 deaths among white soldiers and 10,427 among thecolored in the recent war, a total of 72,448. The total deaths ascribed to thisgroup of diseases in 1917-1919 was only 267, a saving of 72,181 lives. It isperhaps claiming too much to attribute this impressive difference entirely toadvances in sanitation and therapeutics, as other factors such as differences inthe geographical location of the campaigns, questions of the nomenclature andclassification of disease, may have entered into the comparison; but howeverexplained, the impressive fact remains that this enormous saving of life anddisability has been accomplished not only in this group of diseases but in therelated typhoid-paratyphoid group as well. Instead of being the most importantcause of illness and death in the Army, the diarrheal group ranked seventh amongdiseases for admissions, tenth for deaths, and twelfth for days lost from duty.That, nevertheless, these diseases are an ever-present menace to armies, andthat military concentrations, especially under active service conditions, stillpresent dangers from intestinal infections is shown by Table 50, which comparesthe death rates obtaining in the Army during the World War with those of thecomparable age and sex groups in the United States registration area for thesame period. It is seen that the Army rate for dysentery is ten times that ofthe civilians, for diarrhea and enteritis seven times, and for the group as awhole a little more than seven times as great.
|
| U.S. Armyb |
Dysentery | 0.002 | 0.02 |
Diarrhea and enteritis | .007 | .05 |
|
| .009 | .07 |
aCompiled from Mortality Statistics, Bureau of the Census, 1917-1919.
bReports of sick and wounded, S. G. O. 1917-1919.
Certain other facts are brought out by Table 49 which are worthy of more thanpassing notice. The admission rates for the group were approximately the samefor officers and men whether stationed in the United States or in Europe. Thesame is true of the death rates for those stationed in the United States.
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In Europe, however, the death rate for the group is muchhigher for enlisted men than for officers. This fact will be referred to againin the discussion of dysentery. In general, the rates for admissions and deathsin this group are much higher in Europe than is the case with troops in thetraining camps at home. That this was due to the stress of battle conditions isevident from the monthly rates for the diseases in question, which show thatgreat military activity was always accompanied by an increase in the incidenceof diarrhea.
The prevalence of diarrheal disease in our Army in Europe wasundoubtedly greater than the figures of Table 49 would indicate. Many of thecases were of a mild type and as such were not made a matter of record.Moreover, early in the war only hospital admissions were recorded in Europe. Thefollowing quotation gives an idea of the general prevalence of the diarrhealdiseases during the summer of 1918 in the American Expeditionary Forces.2
Epidemic diarrheas, with a considerable amount of dysenteryand probably some unrecognized typhoid and paratyphoid fevers, developed invarious parts of France late in June, appearing first in the more southern areasoccupied by our troops, and wherever insanitary disposal of human wastes, flybreeding, and insufficient precautions in the preparation and serving of foodprevailed. Immediately after the Chateau Thierry operation the troops sufferedquite generally from diarrheal diseases, probably as many as 70 per cent havingbeen so affected. This was inevitable under the conditions of a hard-fought andprolonged battle which made even the elementary principles of sanitationimpracticable of application. Inadequate and ill-prepared food, chilling of thebody at night, polluted water sources, and the plague of flies, which bred andfed upon human excreta everywhere exposed and upon the dead bodies of men anddraft animals upon the battle fields, combined to produced a widespread epidemicof diarrhea among which was a certain proportion of true dysentery andtyphoid-paratyphoid infections. Most of the cases never reached a hospital orobtained medical treatment. Spontaneous recovery in a few days was the rule. Theenthusiasm of the victorious forward movement of the troops carried many menout of reach of hospitalization, and a true measure of noneffectiveness fromthat epidemic can only be guessed. A small number of serious and persistentinfections found their way through the evacuation hospitals to the basehospitals, and of these the great majority examined early in the course of theirdisease were found to be suffering from true dysentery caused by well-knownstrains of bacilli. Fortunately the type of the infection was mild and very fewdeaths resulted from the entire epidemic. The disease prevailed during the warmweather while the fly-breeding season continued. In a few favored places, wheremedical care was combined with adequate physical equipment to avoid fecalexposure and pollution of food and water, only an occasional case of diarrheadeveloped and entire organizations escaped infection, but in the main thedisease prevailed throughout the American Expeditionary Forces from July to themiddle of September.
That these diseases continued through the fall of 1918,during the Meuse-Argonne operation and immediately thereafter, is shown in thefollowing report of the surgeon of the Second Army.3
The movements of the 79th Division troopsduring October and November took them into the region formerly occupied by German troops aroundEtraye, Reville, Crepion, Gibercy, and Damvillers, where the Germans had ahospital with considerable intestinal disease, some of their latrines beingreserved for "intestinal cases." Previous to this the troops, while inaction in November, drank water from shell holes, springs, and wells. Diarrheadeveloped so that estimates of regimental medical officers ranged from 50 to 75per cent of the command.
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A mobile laboratory investigated the outbreak in the 79thDivision and from the report it appears that there were cases reported asdiarrhea which in reality were typhoid fever. The investigation also extended tothe 7th Division, where a great many soldiers were examined for the typhoidcarrier state. Of 100 kitchen personnel examined, 25 per cent gave a history ofhaving had "bowel trouble."
A report from Base Hospital No. 89 shows the difficulty ofclassifying the diseases generally listed as "diarrhea."4
The cases of infectious diarrhea, which come to the hospitalby the score, were nearly always in soldiers who had been ill for many days. The stools of practically every case were examinedbacteriologically, but wewere never able to find ameb? or the organisms of bacillary dysentery, althoughwe all felt sure that the latter was the cause of the symptoms present.Numerous organisms resembling the bacillary types were isolated, but none ofthem agglutinated with known sera.
Of the relatively small bodies of our troops stationed invarious parts of the world other than the United States and Europe, some were intropical countries and such generally suffered more severely from the diarrhealdiseases, especially from true dysentery. By far the highest admission and deathrates for the diarrheal group in white enlisted men in the Army was shown bythe force of about 17,000 men stationed in the Philippine Islands. The admissionrates in Panama were not notably above the average for the group, though therewas a disproportionately large incidence of a nonfatal form of dysentery. The incidence in Hawaii was about the same as that in the United States.
An interesting racial difference appears when the rates forwhite and colored troops are compared. Almost without exception admission ratesin these diseases are definitely higher for the white soldier, sometimes severaltimes as high. On the other hand, the greater fatality of the individual case inthe negro brings his death rate up to or higher than that of the white. Fromthe standpoint of noneffectiveness, the negro shows to excellent advantage, ashis noneffective rate for the diarrheas is definitely less than that of thewhite.
The native Porto Rican and native Filipino soldiers, also ofraces indigenous to the Tropics, manifest no such advantage. After the whites inthe Philippines, these groups showed the highest susceptibility to diarrhealdiseases. It is perhaps possible that the colored American soldier benefitedfrom the effects of discipline and sanitary training. The colored troops in theTropics were in organizations of long service.
There were considerable differences in the rates of differenttraining camps in the United States. In general the camps showing higher rateswere more apt to be located in the Southern States than were camps showing lowrates. The camps showing the highest annual admission rates were Camp Hancock,Ga. (27.21); Camp Beauregard, La. (26.91); Camp MacArthur, Tex. (26.51); andCamp Doniphan, Okla. (27.70). The lowest rates for admissions were Camp Forrest,Ga. (4.34); Camp Eustis, Va. (6.93); and Camp Fremont, Calif., (4.48).
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THE DYSENTERIES
OCCURRENCE
In the discussion of the prevalence of true dysentery duringthe World War it is not permissible to rely exclusively on the records.Statistical tables are not always to be regarded as complete in themselves, norare the various figures of which they are composed to be regarded as conveyingalways entirely truthful impressions, unless they are interpreted with someknowledge of the sources of the information which entered into theircompilation, and of the difficulties which beset those making the originalreports. Several of the difficulties which serve to render the recorded figuresfor the dysenteries an understatement of the actual facts have been brought outin the previous pages. The clinical characters of mild dysentery are so similarto those of a nonspecific enterocolitis that some confusion is to be expected inthe reports of these conditions. It has already been pointed out that the numberof days lost per case in dysentery as reported was much greater than was thecases in the nonspecific diarrheas. One is justified, therefore, in assumingthat, as a class, the cases reported as diarrhea and as enteritis or colitiswere different from and milder than the cases of dysentery. That some cases ofdysentery were included in the epidemics of intestinal disease experienced bythe troops at the front during periods of great military activity has beenindicated by several reports quoted above. Also that an undetermined butprobably large number of these cases escaped hospitalization entirely and wereprobably never reported at all. Of those which did reach hospitals and werereported as cases of diarrhea or enterocolitis, it is probable that many weretrue dysentery, although no specific diagnosis could be made. This was theopinion expressed in the report from Base Hospital No. 98 already quoted.
If a considerable proportion of the more severe dysenterycases were included under the headings "diarrhea" and "enterocolitis"it would serve to increase the average severity of the latter cases and increasethe number of days lost per case, and also the case fatality. Of the 9,604 casesof diarrhea reported in white enlisted men in the United States (Table 49), onlyone proved fatal, a fatality of slightly over one one-hundredth of one per cent.The average duration of these cases was three and three-tenths days. Of the8,921 cases reported from Europe, 16 were fatal, 0.18 per cent, and the averageof the days lost was 20. The corresponding figures for enterocolitis in theUnited States were, case fatality 0.082 per cent with 5.5 days lost per case,and in Europe, fatality 0.43 per cent and 14.7 days lost per case. It is evidentthat some element was present in the European cases which greatly increased theseverity of the average. That this was the inclusion under these headings ofa certain number of cases of true dysentery is probable for all of the reasonsgiven. An exact estimate of the number of cases so included is manifestlyimpossible, but judging from the excess number of deaths per thousand cases inEurope over the corresponding figures from the United States, and applying tothese deaths the case fatality of the reported dysentery cases, it seemspossible that the true incidence of dysentery was not far from
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double that shown in the tables. This conclusion does not inany way vitiate the comparison already given between recent rates and those ofthe Civil War, as that comparison was based on totals of the entire group andnot on dysenteries alone.
ETIOLOGIC TYPES
Here again in order to properly evaluate the figures given itis necessary to appreciate certain facts in regard to the difficulties in thespecific diagnosis of a given case of dysentery. The isolation of the specificdysentery bacilli from the stool of a patient depends for its success upon acombination of circumstances not easily attained under war conditions, indeednot always possible of attainment under most favorable surroundings. After thepossession of adequate facilities the most important of these conditions arethat the stool should have been recently passed, and that the patient shouldhave been in the very early stages of his disease. The latter requirement isprobably explained by the early development in the intestines of thebacteriophage of d'H?relle, which inhibits growth of the specific organism.Under war conditions, therefore, when adequate laboratories were not alwaysavailable, when stools were often necessarily delayed on the way to thelaboratory, and when the majority of patients had been ill for several daysbefore reaching a hospital at which bacteriological work could be initiated, itshould be expected that many, probably a majority, of the cases of truebacillary dysentery should fail of bacteriological confirmation.
In a way the reverse is true of entamebic cases. It is comingto be more and more generally recognized that finding E. histolytica inthe stool does not constitute valid grounds for the diagnosis of amebicdysentery. Of all individuals who harbor the entameba in their intestines, onlya small proportion, probably not over 3 per cent, ever develop dysentericsymptoms. The others remain healthy carriers as evidenced by the more or lessconstant evacuation of the cysts of the organism. When such a carrier becomesaffected with any diarrheal disease, the trophozoites or active vegetative formsof the organism are carried down and evacuated, and their discovery may lead toa diagnosis of amebic dysentery not justified by the facts. As will be shownlater, a considerable proportion of our troops returned from France carryingthis organism in their intestines. It seems probable that a certain percentageof cases on record as amebic dysentery were probably of bacillary origin incarriers of the entameba. Two circumstances fortify this conclusion. First, theentameba is readily identified under the microscope, especially as compared withthe difficult and time-consuming process of isolation of the dysentery bacilli.Secondly, the cytologic methods by which it is now possible to distinguish withgreat accuracy between the two main types of dysentery had not at the time ofthe World War been perfected, but since, in the hands of Willmore and Shearman,5Manson-Bahr,6 and Haughwout,7 have attained great reliability.
All these considerations lead to the conviction that thenumber of cases of bacillary dysentery were understated in the records, thatthat of the amebic cases was overstated, and that the majority of the casesreported as dysentery unclassified were probably in reality of the bacillarytype. This was undoubtedly especially true in Europe where the dysentery casesoccurred in
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epidemic groups since, owing to the biological peculiaritiesof the organism, amebic dysentery is rarely known to occur in epidemicoutbreaks.
Tables 51 and 52 show the incidence of the various types ofdysentery in white enlisted men by months in the United States and in Europe. InEurope bacillary and amebic dysentery and the unclassified group as well, variedin a closely correlated manner. This would hardly be expected in two conditionsepidemiologically so different as bacillary and amebic dysentery. In the UnitedStates, where there were no epidemic outbreaks of the disease, but only theslower seasonal variations, it is possible to compare the curve of theunclassified group with those of the bacillary and amebic cases in theattempt to see which pair are the more closely correlated. The curves are shownin Chart XXXVIII. That for bacillary dysentery ends with 1918, as but one caseof this disease was reported during 1919. It is seen that the curve forbacillary dysentery more closely approximates that of the unclassifieddysenteries than does the curve for amebic cases. The number of casesclassified each month was so small that the comparison loses some of its value,but for as much as it is worth it bears out the conclusion already arrived atthat the great majority of the cases reported in the tables as "dysenteryunclassified" were in fact bacillary cases.
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| Strength |
| Balantidic | Entamobic | Other protozoal | Unclassified | Total | ||||||
Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | ||
| 1917 |
|
|
|
|
|
|
|
|
|
|
|
|
|
April | 183,758 | 0 | --- | --- | --- | 14 | 0.91 | --- | --- | 13 | 0.85 | 27 | 1.76 |
May | 245,454 | 0 | --- | --- | --- | 15 | .73 | --- | --- | 21 | 1.03 | 36 | 1.76 |
June | 309,205 | 3 | 0.12 | --- | --- | 28 | 1.09 | --- | --- | 31 | 1.20 | 62 | 2.41 |
July | 458,817 | 1 | .03 | --- | --- | 11 | .29 | --- | --- | 12 | .31 | 24 | .63 |
August | 562,714 | 5 | .11 | --- | --- | 24 | .51 | --- | --- | 12 | .26 | 41 | .87 |
September | 776,466 | 12 | .19 | --- | --- | 19 | .29 | --- | --- | 52 | .80 | 83 | 1.28 |
October | 1,032,244 | 9 | .10 | --- | --- | 19 | .22 | 1 | 0.01 | 33 | .38 | 62 | .72 |
November | 1,061,422 | 14 | .16 | --- | --- | 28 | .32 | 2 | .02 | 13 | .15 | 57 | .64 |
December | 1,129,065 | 1 | .01 | --- | --- | 28 | .30 | --- | --- | 3 | .03 | 32 | .34 |
| 1918 |
|
|
|
|
|
|
|
|
|
|
|
|
|
January | 1,096,434 | 1 | .01 | 1 | 0.01 | 16 | .18 | --- | --- | 15 | .16 | 33 | .36 |
February | 1,095,039 | 1 | .01 | --- | --- | 3 | .03 | --- | --- | 9 | .10 | 13 | .14 |
March | 1,129,223 | 6 | .06 | --- | --- | 11 | .12 | 1 | .01 | 29 | .31 | 47 | .50 |
April | 1,168,558 | 5 | .05 | --- | --- | 13 | .13 | --- | --- | 30 | .31 | 48 | .49 |
May | 1,197,757 | 10 | .10 | --- | --- | 30 | .30 | --- | --- | 39 | .39 | 79 | .79 |
June | 1,303,746 | 12 | .11 | --- | --- | 27 | .25 | 2 | .02 | 86 | .79 | 127 | 1.17 |
July | 1,328,513 | 6 | .05 | --- | --- | 35 | .32 | 4 | .04 | 56 | .51 | 101 | .91 |
August | 1,284,247 | 4 | .04 | --- | --- | 15 | .14 | 2 | .02 | 53 | .50 | 74 | .69 |
September | 1,321,440 | 5 | .05 | --- | --- | 27 | .25 | 1 | .01 | 57 | .52 | 90 | .82 |
October | 1,343,933 | 1 | .01 | --- | --- | 12 | .11 | 1 | .01 | 19 | .17 | 33 | .29 |
November | 1,255,195 | 1 | .01 | --- | --- | 15 | .14 | 1 | .01 | 21 | .20 | 38 | .36 |
December | 941,219 | 2 | .03 | --- | --- | 15 | .19 | 1 | .01 | 12 | .15 | 30 | .38 |
| 1919 |
|
|
|
|
|
|
|
|
|
|
|
|
|
January | 672,937 | 0 | --- | --- | --- | 11 | .20 | --- | --- | 18 | .32 | 29 | .52 |
February | 471,815 | 0 | --- | --- | --- | 5 | .13 | --- | --- | 10 | .25 | 15 | .38 |
March | 406,839 | 0 | --- | --- | --- | 5 | .15 | --- | --- | 8 | .24 | 13 | .38 |
April | 339,836 | 0 | --- | --- | --- | 2 | .07 | --- | --- | 8 | .28 | 10 | .35 |
May | 291,810 | 0 | --- | --- | --- | 7 | .29 | --- | --- | 11 | .45 | 18 | .74 |
June | 246,903 | 0 | --- | --- | --- | 7 | .34 | --- | --- | 3 | .15 | 10 | .49 |
July | 215,104 | 0 | --- | --- | --- | 5 | .28 | --- | --- | 0 | --- | 5 | .28 |
August | 156,791 | 0 | --- | --- | --- | 2 | .15 | --- | --- | 1 | .08 | 3 | .23 |
September | 149,360 | 0 | --- | --- | --- | 3 | .24 | --- | --- | 4 | .32 | 7 | .56 |
October | 139,877 | 0 | --- | --- | --- | 2 | .17 | --- | --- | 3 | .26 | 5 | .43 |
November | 132,403 | 0 | --- | --- | --- | 3 | .27 | --- | --- | 3 | .27 | 6 | .54 |
December | 135,441 | 1 | .09 | --- | --- | 1 | .09 | --- | --- | 1 | .09 | 3 | .27 |
| Total | 1,965,297 | 100 | .05 | 1 | 0 | 458 | .23 | 16 | .01 | 686 | .35 | 1,261 |
|
330
| Strength |
| Balantidic | Entamobic | Other protozoal | Unclassified | Total | ||||||
Absolute numbers |
| Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | Absolute numbers | Annual ratios per 1,000 | ||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
April | 13,420 | 1 | 0.89 | --- | --- | --- | --- | --- | --- | 1 | 0.89 | 2 | 1.79 |
July | 28,821 | 2 | .83 | --- | --- | 1 | 0.42 | --- | --- | 4 | 1.67 | 7 | 2.91 |
August | 50,882 | --- | --- | --- | --- | --- | --- | --- | --- | 1 | .24 | 1 | .24 |
September | 70,266 | --- | --- | --- | --- | 1 | .17 | --- | --- | 2 | .34 | 3 | .51 |
October | 92,139 | --- | --- | --- | --- | 3 | .39 | --- | --- | 2 | .26 | 5 | .65 |
November | 123,429 | --- | --- | --- | --- | 3 | .20 | --- | --- | 7 | .68 | 10 | .97 |
December | 160,178 | --- | --- | --- | --- | 2 | .15 | 1 | 0.07 | 9 | .67 | 12 | .90 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
January | 193,264 | 3 | .19 | --- | --- | 1 | .06 | --- | --- | 5 | .31 | 9 | .56 |
February | 223,130 | 1 | .05 | --- | --- | 0 | --- | --- | --- | 2 | .11 | 3 | .16 |
March | 283,268 | 2 | .08 | --- | --- | 3 | .13 | --- | --- | 3 | .13 | 8 | .34 |
April | 388,048 | 0 | --- | --- | --- | --- | --- | 1 | .03 | 5 | .16 | 6 | .19 |
May | 587,240 | 1 | .02 | --- | --- | 3 | .06 | 0 | --- | 5 | .10 | 9 | .18 |
June | 796,427 | 1 | .02 | --- | --- | 2 | .02 | 0 | --- | 7 | .11 | 10 | .15 |
July | 1,063,192 | 55 | .62 | 3 | 0.03 | 8 | .09 | 2 | .02 | 53 | .60 | 121 | 1.37 |
August | 1,266,592 | 67 | .63 | 1 | .01 | 21 | .20 | 2 | .02 | 275 | 2.61 | 336 | 3.47 |
September | 1,527,793 | 34 | .27 | --- | --- | 25 | .20 | 2 | .02 | 314 | 2.47 | 375 | 2.95 |
October | 1,635,321 | 38 | .28 | --- | --- | 11 | .08 | 4 | .03 | 493 | 3.64 | 546 | 4.01 |
November | 1,682,836 | 9 | .06 | --- | --- | 13 | .09 | 0 | --- | 239 | 1.70 | 261 | 1.86 |
December | 1,591,962 | 5 | .04 | --- | --- | 6 | .05 | 1 | .01 | 91 | .69 | 103 | .78 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
January | 1,488,683 | 3 | .02 | --- | --- | 6 | .05 | --- | --- | 26 | .21 | 35 | .38 |
February | 1,310,083 | 1 | .01 | --- | --- | 5 | .05 | --- | --- | 22 | .20 | 28 | .26 |
March | 1,115,693 | 0 | --- | --- | --- | 1 | .01 | --- | --- | 2 | .02 | 3 | .03 |
April | 853,425 | 0 | --- | --- | --- | 1 | .07 | --- | --- | 3 | .04 | 8 | .11 |
May | 569,842 | 0 | --- | --- | --- | 0 | --- | --- | --- | 0 | --- | 0 | --- |
June | 271,633 | 0 | --- | --- | --- | 0 | --- | --- | --- | 5 | .22 | 5 | .22 |
July | 111,634 | 4 | .43 | --- | --- | 1 | .11 | --- | --- | 4 | .43 | 9 | .97 |
August | 48,006 | 15 | 3.75 | --- | --- | 1 | .25 | --- | --- | 6 | 1.50 | 22 | 5.50 |
September | 30,315 | 0 | --- | --- | --- | 2 | .79 | --- | --- | 1 | .40 | 3 | 1.19 |
October | 21,055 | 1 | .57 | --- | --- | 1 | .57 | --- | --- | 0 | --- | 2 | 1.14 |
November | 18,920 | 0 | --- | --- | --- | 0 | --- | --- | --- | 0 | --- | 0 | --- |
December | 18,379 | 0 | --- | --- | --- | 0 | --- | --- | --- | 0 | --- | 0 | --- |
Not stated | 18,379 | 0 | --- | --- | --- | 0 | --- | --- | --- | 3 | --- | 3 | --- |
| 1,469,656 | 243 | .17 | 4 | 0 | 125 | .09 | --- | --- | 1,590 | 1.08 | 1,975 | 1.34 |
Seventy per cent of the dysentery cases were reported withoutetiologic classification (Table 53), 47 per cent in 1917, 78 per cent in 1918,and 52 per cent in 1919. The proportion so reported varied greatly from month tomonth, usually highest when the absolute number of cases was greatest especiallyin the European cases. Of the classified cases, those reported as amebicconsistently exceeded those called bacillary. During the World War (Table 53)there were reported 926 amebic cases to 460 demonstrated as bacillary, aproportion of nearly 2 to 1. Inasmuch as, combined, these two groups representedless than a third of the cases of dysentery, and as we have shown theprobability that most of the other two-thirds were of bacillary origin as wellas perhaps some that were reported as amebic, we shall not be greatly in errorif we assume that the true proportion should be not far from five cases of bacillary dysentery to eachamebiccase.
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|
| Bacillary | Balantidic | Amebic | Other protozoal | Unclassified |
Total dysenteries in 1917 | 688 | 69 | 2 | 291 | 3 | 323 |
| United States | 484 | 50 | 0 | 195 | 2 | 237 |
| Europe | 41 | 3 | 0 | 10 | 1 | 27 |
Total dysenteries in 1918 | 3,573 | 325 | 6 | 428 | 30 | 2,784 |
| United States | 883 | 70 | 2 | 239 | 14 | 558 |
| Europe | 2,431 | 244 | 4 | 105 | 15 | 2,063 |
Total dysenteries in 1919 | 577 | 66 | 2 | 207 | --- | 302 |
| United States | 151 | 3 | 0 | 62 | --- | 86 |
| Europe | 188 | 31 | 0 | 43 | --- | 114 |
|
| 4,838 | 460 | 10 | 926 | 33 | 3,409 |
A few cases, as shown in the tables, were reported as ofbalantidic or other protozoal origin. The former organism is generallyrecognized as occasionally pathogenic with the production of chronic dysentericsymptoms. As for ciliates or other protozoa, however, the evidence of theirpathogenicity is very doubtful, and the opinion is rather generally held amongthose qualified to judge that the finding of ciliates in a case of dysentery isan accidental occurrence without significance etiologically. In any case thenumber of cases so reported was so small as to merit no further considerationhere.
PREVALENCE AND DISTRIBUTION
Bearing in mind the considerations just stated and theconclusions that in all probability the actual number of cases of true dysenterywas twice that reported in the tables, and further that the reported proportionof amebic to bacillary cases can not be relied upon, but that we shall notgreatly err if we assume that there were in fact about five bacillary cases toeach of the amebic type, it is still possible to glean from the tables asreported information of great comparative value. It is possible to state fromthem the relative incidence in different countries and in different races.
Of the 4,738 cases of dysentery reported, between April 1,1917, and December 31, 1919, 254 were in officers and 3,547 in white enlistedmen. The incidence of reported cases in officers was 1.23 per thousand perannum, while that for enlisted men was 0.99. One death only occurred among theofficers and 54 among the white soldiers. The latter figure gives a death rateof 0.02 per thousand per annum, while the officers' rate is too small to beconsidered and is recorded as 0. In the troops in the United States there were107 cases in officers (0.86 per 1,000 per annum) and 1,261 in white enlisted men(0.64). One officer and 14 enlisted men (white), died, a death rate in each caseof 0.01 per thousand per annum. In Europe there were 133 cases in officers (1.80)and 1,975 among the white enlisted men (1.34), while there were no deaths fromdysentery among officers and 35 among white soldiers (an annual rate of 0.02per thousand).
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These figures show that both in Europe and in America theincidence of dysentery was higher among officers than among enlisted men, butthat, among officers, the type of the disease was less severe, the death rates,low as they were, were higher in the case of the enlisted men. The incidenceamong officers was a little more than twice as high in Europe as in the UnitedStates and the relative proportion among enlisted men comes to exactly the samefigure, in Europe being two and nine hundredths times the incidence of those inthe United States. Remembering the practical certainty that many other dysenterycases occurred in the troops in Europe, we must assume that the true ratio ofincidence in Europe to that in the United States was probably nearer 4 than 2 to1. The type of the disease was more severe in Europe, or perhaps treatment lessprompt and efficacious on account of battle conditions. This is shown by thedifference in the case fatality in the two places, 1.11 per cent in the UnitedStates and 1.77 per cent in Europe. This difference is less than couldreasonably be expected considering the difference in conditions. Comparisons ofthe number of cases of discharge for disability between Europe and America arevalueless, as large numbers of men were so discharged in America for diseaseoriginally contracted in France. There were 70 cases discharged for disabilityin the United States and only 8 in Europe. The greater severity of the Europeancases is further shown by the average number of days lost per case, 24.6 in theUnited States and 31 in Europe. These figures are for all types of dysentery. Adivision into bacillary and amebic types would bring the figures down to suchsmall size as to render averages valueless and conclusions unreliable.
In the Philippines, white troops encountered a more severetype of dysentery and conditions which rendered them more likely to contract thedisease than was the case at home. Their rate of 8.94 per thousand per annum wasmore than four times the rate for the troops in Europe for the entire warperiod (1.34). In October, 1918, at the height of military activity in Francethere was a reported rate of 4.01. As this was the time when the greatest numberof cases necessarily went unreported, and as by no means all of our troops inFrance were in the battle area, it is evident that the troops in the battle areamust have been exposed to infection much more effectively than was the case inthe Philippines for troops living under peace conditions. The Filipino strain ofdysentery was more fatal, however, as is shown by the comparison of the casefatality rates, 1.77 per cent in Europe and 2.63 in the Philippines. The yearlydeath rate per thousand in the Philippines was 0.24, twelve times that of theArmy as a whole.
In Hawaii, the case rate for white enlisted men was far belowthe average for the Army and there were no deaths. In Panama, 28 cases gave arate of 1.42 per thousand per annum, but there were no deaths. This does notnecessarily indicate a milder type of the disease, as the case fatalityelsewhere was so low, from 1 to 2 per cent, that deaths would hardly be expectedamong 28 cases.
All the figures in the comparisons given above relate towhite enlisted men or officers. Some interesting points are brought out by thestudy of the figures for the colored troops. (Chart XXXIX and Table 49.) In thefirst place, for the whole Army the incidence rates for the colored troops are20 per cent lower than
333
334
those for white troops, while their death rates are 50 percent higher. The negro appears less likely to become infected with dysentery,but offers less resistance to the disease once acquired. The case fatality inthe colored was 3.64 per cent for the whole Army; that in the white troops 1.52.The number of cases in the colored troops, 220 for the entire period, was sosmall, however, as to somewhat lessen the value of this comparison. The ratesfor colored troops were lower in Europe than in the United States. This strikingdifference must have been due to the large proportion of colored troops engagedin work under the better sanitary conditions of the Services of Supply. That therate was actually lower than in the camps at home may be interpreted assupporting the idea already advanced that seasoned troops are less susceptibleto intestinal infection than are recruits. In the Philippines the coloredincidence rate of 2.92 was also strikingly lower than the rate for the whites,and there were no deaths among colored troops. Here again the small number ofcases involved prevents drawing conclusions.
In Hawaii there were no cases of dysentery among 3,319colored soldiers.
Of the native troops, serving in their home environment, theFilipinos and the Porto Ricans showed to poor advantage, having the highestincidence rates, 5.98 and 6.76, respectively, after the white troops in thePhilippines. The number of deaths was so small as to render averages withoutvalue, but their rates as shown were far above those of the Army as a whole.
INCIDENCE BY MONTHS
Chart XL shows the varying monthly incidence of the totalreported cases of dysentery in enlisted men in the United States and in Europe.It is seen that there is some tendency for the occurrence of higher rates duringthe summer months, with a distinct lessening of the incidence in cold weather.In the United States the rates were higher during the first three months of thewar period than was the case at any time later. This fact already has beenmentioned in the discussion of the incidence of the total diarrheal group. Thereasons for the high rate at this time are not apparent. Of the 125 cases ofdysentery reported from the white enlisted men in the United States for thesethree months, 57 were of the entamebic type, only 3 recognized as bacillary, andthe balance, 65, were unclassified etiologically. These figures suggest thatthe accessions to the Army during that period of voluntary recruiting brought inan unusually large number of persons infected with the entameba. From thisinitial high point in June, 1917, there was a nearly uniform gradual fall in therates until February, 1918, when they began to rise toward the second relativelyhigh point in June of that year. From June, 1918, until May, 1919, the tendencywas again downward, although the winter fall was not as low as in the previousyear. From May, 1919, to the end of the year there were irregular rises andfalls in the rates, but the absolute numbers of cases were so small at thistime that the figures possess little value. It can be said, however, that thereis little or no indication of a definite summer rise in 1919. Chart XXXVIII,which shows the monthly incidence rates for the bacillary and entamebic types ofdysentery separately, together with the unclassified group, shows also
335
that in general the curves of the three classes of casesfollow the same course with such minor divergencies as are to be expected fromthe small numbers of cases involved.
In Europe, too, a relatively high rate was observed in thesummer of 1917. This is of little significance, however, as it was the result ofseven cases in a strength of about 29,000. Two of the caseswere reported as bacillary, one as entamebic, and four were unclassified. During the winter of1917-18 the rates in Europe did not fall as low as those in the United States,but the summer rise was delayed until July, when decided military activitybegan, and a decidedly high rate prevailed until after the armistice began.From then until the follow-
336
ing summer the Army in Europe showed very low rates, muchlower than was the case at home during the same period. In August and September,1919, however, the rates again shot up to reach a point higher than was reportedat any time during active operations. This outbreak, however, consisted of only22 cases in a strength of about 48,000 men; 15 of the cases were recorded asbacillary, 1 as entamebic, and 6 were not classified. Perhaps the fact that atthis time the army of occupation had received a large number of newly recruitedreplacements may account for this small outbreak. Leaving out of considerationthis late peak and the one of July, 1917, on the grounds that the number ofcases involved was too small to be significant, it is seen that the only highrates in the Army in Europe were those which occurred during periods of intensemilitary activity. The conditions which of necessity prevailed during thosemonths of battle will be described later. The death rates from the dysenteries,both in Europe and America, fluctuated so irregularly, due to the small numberof cases involved, as to make their consideration useless. The sameconsiderations prevent any conclusions from being drawn from the monthlyincidence of cases among colored soldiers, or the troops in other countriesthan the United States and Europe.
ETIOLOGY
In spite of intensive study on the part of all the armiesinvolved, the World War added very little of moment to our knowledge of theetiology of these conditions. Much work was done in the laboratories on thespecific etiological agents, particularly of the bacillary types, and muchexperience accumulated confirming the knowledge previously attained as to theimportance of food, feces, flies, and fingers in the mechanical transfer of thepathogenic agents. The influence of climate has long been known, and the higherrates to be expected in tropical and subtropical countries were experiencedduring the war as shown by the incidence in the Philippines and to some extentin Panama. The effect of race has already been discussed, and it has been shownthat the colored soldier appeared to have less tendency to contract dysenterythan the white soldier, but that once attacked his chances of death weregreater.
More interesting and important is the consideration of thepredisposing causes incidental to war conditions as shown by reports from theAmerican Expeditionary Forces. In the camps at home conditions were well undercontrol. In battle sanitary discipline usually was impossible of enforcement,and during the military operations at Chateau Thierry, St. Mihiel, the ArgonneForest, and elsewhere dysentery and other diarrheal conditions prevailed inepidemic form. Of the many descriptions of such outbreaks a few have beenselected to give an idea of the conditions which prevailed.
August 6, 1918, a mild type of bacillary dysentery wasreported in the First Army and a request made of the director of laboratories atDijon to send an officer to investigate it.8 Accordingly a medicalofficer reported at First Army headquarters9 and began a study of the epidemicwhich had existed in that sector since early in July. It was difficult todetermine the prevalence of the disease, as perhaps not more than 2 per cent ofthe cases were hospitalized and sick call was held very irregularly. At the timeof the call for an investigation the 3d Division had 500 cases, with 60 inhospital, the 28th Division 300
337
cases, with 1 in hospital, and the 32d Division 1,200 cases,with 20 in hospital. In the 1st Battalion, 165th Infantry, it was estimated that70 per cent of the command had diarrhea. The nature of the disease is shown bythe following quotation from the report of the investigator.9
The large majority of the cases were clinically characterizedby a simple though severe diarrhea, usually coming on suddenly and, in somecases, resembling the effects of a saline purge. Many cases subsided withouttreatment of any kind. Many yielded to simple treatment with saline cathartics,or castor oil, followed by bismuth. A great many cases persisted for three orfour days and a percentage variously estimated at from 3 to 5 lasted longer andhad blood and mucus in the stool. About the same percentage had a temperature of100? or over, and a number of cases were seen by the undersigned in which thetemperature was 102?, some even going up to 104?. In these cases also therewas tenesmus. In many cases there were systemic symptoms consisting of pain inthe muscles and back and feeling of great prostration. In the writer's owncase, and in that of several nurses and doctors observed, systemic symptoms andprostration were noted. Then the condition was one of diarrhea which in perhaps90 per cent of the cases was not accompanied by severe systemic symptoms,disabling the men merely for one, two, or three days. Among these cases,however, there were more severe ones, some of which took on the form of moderatetrue dysentery, a very few showing the picture of severe types of dysentery.
The report stated that diarrhea of a similar type wasprevalent among neighboring French troops. Water in the entire area was bad; B.coli was present in all examinations, and it could not be regarded as safewithout chlorination or boiling. Efforts at chlorination had been general, butit was frankly stated that during the time of battle it was quite impossible tochlorinate the water for the men in the more advanced posts and later it wasfound that water was not being chlorinated in many commands, owing in some casesto the difficulty in obtaining calcium hypochlorite. In this connection theinvestigator stated:9
It is our opinion that the disease may have been started bythe drinking of unboiled water from contaminated sources and that some of it isbeing kept going in this way; nevertheless that this was not the only and maincause of the continuance of the disease was shown by such examples as thefollowing: Mobile Hospital No. 2 had had nothing but chlorinated water since thebeginning and have taken good care of their latrines, but have always been nextto units with open latrines and many flies. At least 10 per cent of the commandhas had diarrhea. The 146th Field Artillery, as reported by Captain Stark, hadonly boiled water for a short period during which diarrhea appeared. Since thiscommand, however, was subsequently scattered and detachments could not becontrolled as far as drinking from unauthorized sources was concerned, watercould not entirely be excluded as being in part at least responsible, and 8 outof every 10 men have had the disease.
Sanitary conditions throughout this entire area wereatrocious. At first, of course, there were many unburied bodies of men andhorses throughout the area; at the time of the arrival of the undersigned, humanbodies had been buried, but there were still many unburied horses. The writer nolonger saw any unburied human bodies, but was told that until a few days beforeAugust 10 there had still been unburied bodies and many had not been buried verydeeply. Major McKoy told the writer of some German bodies that he had seenseveral days after the writer arrived, buried with the hands sticking out of theground, and there were areas of the country in which on riding through in anautomobile one passed through a strongly noticeable stench.
Feces disposal except in a few instances was in a conditionof utter neglect. To describe well-cared-for latrines would consist merely inpicking out a few exceptions. The wretched conditions of the latrines appliednot only to the front and forwarded areas, but also to areas as far back as Ussy.Many latrines were seen, some at Ussy, some in the town
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of Chateau Thierry, and many in other places, consisting ofshallow ditches, half or more filled with feces, with no attempt whatever toeven cover them with dirt. Flies swarmed in and about them, and in some casessuch as the latrine in the Chateau de la Foret near Ville Moyenne, and one inthe medical supply depot of the 32d Division in Chateau Thierry, they werewithin short distances of messes. In addition to this, feces were depositedwithout any regard to latrines. In many of the woods occupied by troops therewere piles of feces here and there throughout the area, on the ground,uncovered, with the paper used for cleansing purposes scattered irregularlyabout them. This was true not only of woods in the forward areas, but in suchplaces as gardens at the backs of houses, such as, for instance, the onementioned above in Chateau Thierry at the medical supply depot of the 32dDivision. Again the men in the forward areas had made use, for defecating, ofthe shallow trenches dug for the immediate protection of a few men at a time,and no attempt had been made to cover them. This condition was true of placeslike the woods occupied by the 304th Field Artillery, and at Moreuil where the77th Division units entered places previously occupied by units of the 4thDivision and found them in the condition described above.
The abundance of flies was greater than the writer has everseen anywhere before. This was probably due to the fact that the areas had beenso thickly covered by breeding places, dead bodies of animals and men, andmanure, and because of the coincident hot weather. During the early part of thewriter's stay it was impossible to sit at a mess and eat any of the foodplaced on the table before myriad flies had settled upon it, and the tables inthe kitchen and the food in the kitchen were at all times covered with flies.
The investigator concluded his report by saying that it wasbelieved the epidemic of diarrhea which had been prevalent in the Paris group ofthe First Army was not due to any single cause. It was believed to have beenstarted by the drinking of unchlorinated water and the contamination of food byfeces; and kept alive chiefly by flies in this latter manner.
Medical officers were advised by the chief surgeon, A. E. F.,of the insanitary conditions as follows:10
Intestinal flux has been quite prevalent recently in theAmerican Expeditionary Forces. Whether we call it cholera morbus, dysentery,diarrhea, enterocolitis, or acute intestinal indigestion, we can not blink thefact that the causes of practically every case have been preventable and wellwithin the control of the officers and men of the American Expeditionary Forces.The ingestion of dirty food and water is the simple and the correct explanationof the extensive epidemics which have caused a large burden of unnecessarysuffering and inconvenience to our men in every part of France. The dirt has in99 per cent of the cases been our own dirt and the food and water have beenof our own providing. Feces have got into the food. All varieties of infectingorganisms familiar to dwellers in temperate zones and plenty of tropicalorganisms have been identified. Among them the commonest have been Shiga,Flexner, Hiss-Y, Wheeler, paratyphoid, and the Entameba histolytica.
Do not unload the responsibility for summer diarrhea upon thefilthy fly; carriers-i. e., men sick with diarrhea, typhoids, dysenterics,etc-have served food in many kitchens. Officers and men, even in parts ofFrance far from the turmoil and disorganization of the recently captured areassouth of the Vesle, constantly drink water from unapproved sources in utterdisregard of orders issued for their protection. A diarrhea of only one day,followed by three days of constipation, in a negro private of Engineers wasfound to be due to the Flexner bacillus. Most of those clinically recovered fromwhat seems a simple dietetic diarrhea continue, as do typhoid convalescents, tospread their infection by hand contact with their fecal discharges. That Francehas been well seeded must be acknowledged if one will but count the harvest. Itis verily in our own hands to prevent a continuance or a recurrence.
This graphic picture of the conditions allowed to persistafter a great battle, as well as the opinion expressed from headquarters, showswhat may be expected when the lessons of sanitary discipline have not beensufficiently
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well ingrained upon new troops. Had the germs of cholera oreven of typhoid fever been present instead of the comparatively mild strain ofdysentery bacilli, the results would have been calamitous. That the AmericanExpeditionary Forces learned its lesson and perfected its sanitary discipline isshown by the remarkably low rates for intestinal diseases which followed thesigning of the armistice and to which attention has already been called.
The conditions just described served as a causative factor inthe occurrence of both major types of dysentery as well as of other intestinalinfections grouped in the reports as diarrhea and as enteritis and colitis. Theresults of such conditions have long been known and they are repeated here onlyto emphasize the lesson they teach.
In the matter of specific etiology of the dysenteries littleof importance was added to the sum of our knowledge by the extensive researchconducted not only in the laboratories of the American forces but also by allthe other armies engaged. It would appear from the reports that the outbreaks ofdysentery during the period of active military operations differed from thoseusually occurring in civil life in being of mixed etiology. In civil life anoutbreak of dysentery is usually the result of one type of organism and allcases show the same type and all are directly or indirectly due to the samesource of infection. In such conditions as those just portrayed, where perhapshundreds of thousands of men are involved, the chances for the spread ofinfection are so favorable that several different strains or varieties oforganisms find it easy to get a foothold and so not all the cases of the sameoutbreak are due to the same bacterial agent. In the outbreak described, theinvestigator9 reported that:
In several instances, dysentery bacilli were isolated whichagglutinated in Shiga serum, but showed some slight irregularity on the Russelldouble sugar medium. But since the stock Shiga bacilli brought from Dijonshowed the same irregularity on this medium, one felt justified in regardingthese organisms as of true dysentery. In one case bacilli of the Flexner typewere isolated. Dysenterylike organisms, but unidentified, were isolated fromother cases. In two cases paratyphoid bacilli, probably B. paratyphosus wereisolated from the blood.
The difficulties of isolation of this group of bacteria evenunder favorable circumstances have been described. It is therefore to beexpected that no large proportion of successful isolations will result from anygiven outbreak. A few typical instances of investigations in the field follow.
In July, 1918, an epidemic of diarrhea was reported among thepersonnel of the 355th Infantry at Grand.11 During the 17 days covered bythe report there were about 170 cases. Examination of the stools was negativefor organisms of the typhoid-dysentery group and for ameb?. The blood was alsonegative. The outbreak was attributed to the use of polluted water.
An outbreak of diarrhea in August, 1918, in A. R. C. BaseHospital No. 111 and in Evacuation Hospital No. 5, at Chateau Thierry, wasinvestigated.12 Eighty cases were examined bacteriologically.B. dysenteri? Shiga was found in 4, the Flexner variety in 1, the"Y" type in 2, and the B. paratyphosus B in 2.
An investigation of an epidemic among troops in Camp No. 1and troops in the vicinity of St. Nazaire, in August, 1918, failed to reveal anyorganisms of the dysentery group.13 The outbreak was thought to bedue to bacterial infection of a mild type and spread most probably by water andflies.
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An officer of the base laboratory, intermediate section,reported cases of diarrheal disease at Romorantin and Gievres.14Nocases of dysentery were diagnosed at the former place, but diarrhea had beencommon. At Gievres one case each yielded B. dysenteri? (Morgan 1) and B.dysenteri? (Shiga). The cases were not of a severe type.
An epidemic in the 37th Division was investigated and inOctober, 1918, it was reported that the Shiga bacillus had been isolated fromsoldiers and from civilians living in the vicinity.15 The caseswere attributed to water and to contact infection through flies.
The nature of an atypical dysentery-like bacillus found atthe embarkation hospital, Newport News, Va., was investigated in September,1918.16 The theory was advanced that the change in environment resulting fromany intestinal disturbance, constipation, diarrhea, etc., invariably changed thenormal flora and resulted in an increase of atypical, nonlactose, fermentingbacilli which often outgrow the causative agent. The conclusions drawn from thisinvestigation were as follows:17 (a) The investigation failedto establish any causal relationship between atypical bacilli and dysentericinfection. (b) Repeated bacteriological tests are of value in makinga diagnosis. (c) Where bacteriological results are negative or doubtful,serological tests may prove of value in establishing the cause of infection.
The importance of early examination of stools was shown bythe experience with 1,050 cases from which 158 successful isolations were made.Sixty-eight per cent of the successful isolations were made in the first fivedays of the disease, after which the percentage of positive results rapidlydiminished whether the dejecta remained characteristically dysenteric or not.
During the World War there was a tendency on the part of someworkers further to subdivide the already complicated group of dysentery bacilli.Thus several varieties of para-Shiga and of para-Flexner bacilli made theirappearance. The truth will probably prove to be that there are two species ofdysentery bacilli represented by the Shiga and Flexner types, and that otherslightly different organisms are varieties of the two main species which willprove to be more or less interchangeable. The British investigators, Willmoreand Shearman,5 made the statement that almost weekly a new type of bacillus,nonmotile Gram-negative anaerogenic, nonlactose fermenting, turned up on theirplates. Each new type showed infinite gradation affinities with, and divergencefrom, the classical in its bearing toward recognized agglutinating sera andfermentation of sugars.
From the consideration of all the reports it is apparent thatwe emerged from the war with the original Shiga type as the most importantetiological factor in the bacillary dysenteries; the Flexner comes second. Thereare several allied organisms beside the paratyphoid B which seem to have enteredinto the production not only of true clinical dysentery but of the milderdiarrheas as well.
Little has been added to our knowledge of the etiology ofentamebic dysentery as the result of the war. Two new species of apparentlynonpathogenic ameb? were discovered in British laboratories. The E. nana ofWenyon and O'Connor,18 and the Dientameba fragilis of Jeppsand Dobell.19 The former is important in the diagnosis of entamebacarriers, as the cysts at times
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resemble those of E. histolytica. Kofoid, Kornhauserand Plate20 found E. nana to be the commonestameba found inreturned American troops in the large series of examinations which theyconducted.c
CARRIERS
Opinions have been divided as to the importance of carriersin the epidemiology of bacillary dysentery. The importance of the carrier inentamebic dysentery is unquestioned. Russell21 regarded acute and chroniccarriers of dysentery bacilli as equally as important in the propagation ofdysentery as are typhoid carriers in the spread of typhoid fever. He arbitrarilyconsidered a patient a carrier if bacilli persisted in his discharges more thanthree months from the date of first symptoms. There is usually a clear historyof dysentery. Carriers of the Flexner bacillus may remain free from symptoms andshow no abnormalities in the stools. Shiga carriers, on the other hand, are moreapt to present the picture of chronic cases, seldom recovering, even for a shorttime, sufficiently to be considered healthy. He called attention to theintermittent character of the discharge of bacilli in known carriers.
The carrier of dysentery bacilli, according to Nichols,22is apparently of less importance in the spread of bacillary dysentery thanare carriers in the spread of typhoid fever and cholera. There are fewer truecarriers in bacillary dysentery; the individual carrier is less chronically illand excretes fewer bacteria. The spread of infection is usually due to acute andchronic cases. Incubationary carriers are known; however, in view of the absenceof a test for susceptibility, and in view of the relapsing character of theattack, it is difficult to diagnose them. In temporary convalescent carriers,the excretion of bacilli diminishes after clinical recovery. According toNichols, the number does not become low for about two months, and it requiresrepeated examinations to exclude the carrier state. Chronic convalescentcarriers on the other hand, running up to 1 year, occur in from 1 to 5 per centin different series. It is difficult to draw the line between relapsing carriersand chronic cases. Nichols and Russell agree on the difference between Flexnerand Shiga cases from the carrier standpoint. The Flexner cases are more apt toresult in the carrier state while the Shiga cases tend to become chronic.Nichols concluded that contact carriers have usually been considered rare, butwith improvement in the technique of examination they have been found morefrequently.
The percentage of cases that became carriers and theproportion of examinations that resulted in positive findings of dysenterybacilli were variously reported by different workers. Arkwright, Yorke,Priestley, and Gilmore23 examined 50 dysentery convalescents forthe carrier state. The cases varied from three to six months after the onset ofsymptoms. The Shiga bacillus was found in two and E. histolytica in nine.Kennedy and Rosewarne24 examined several hundred typhoid and dysenteryconvalescents for the detection of carriers. More than 5,000 examinations weremade. The results showed 6 dysentery carriers, of which 3 were of the"Y" type and 3 Shiga. Fletcher and Mackinnon25 examined 935dysentery convalescents and 847
cFor further details in this connection, consult Chapter XIX of this volume.
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convalescents from other diseases, such as enteric and trenchfevers. Among the dysentery convalescents, 6.95 per cent were found to bedysentery carriers; 2.78 per cent persisted in the carrier state. There were 58carriers of the Flexner organism and 13 of the Shiga. Of the nondysentericcases, 1.06 per cent were carriers of dysentery bacilli. Two-thirds of thesepatients gave a history of dysentery; all were of the Flexner type. All theShiga carriers were persistent and suffered from chronic dysentery and mentaldepression. The Flexner carriers were usually in good condition and fit for workunder favorable conditions. The carrier of Flexner bacilli does not excrete theorganism continuously but intermittently, with periods of perhaps five or sixweeks during which it can not be found. This renders the diagnosis of thecarrier state extremely difficult and indicates the necessity of frequentexaminations over a considerable period before a given patient may safely beconsidered free from bacilli.
According to Dopter,26 the main source ofentamebic infection during the war was the presence of carriers of the organismamong the French colonial troops from North Africa. These men infected the soilof the trenches they occupied, and healthy troops relieving them became infectedin their turn. Thus with the general interchange of troops the infection becamewidely scattered. The number of cases was never large enough to menace militaryeffectiveness, but sanitarians were preoccupied with the thought that thecreation of an army of entameba carriers might present a serious problem to thecountries concerned on the return of their soldiers to civil life.
Sporadic cases of entamebic dysentery have been known foryears in all parts of the United States, but the condition has remained somewhatof a pathological curiosity. However, during the Mexican border mobilization in1916, Craig27 identified the organism in 158 cases of dysentery amongsome 110,000 men. The cases were milder than those usually seen inthe Philippine Islands, possibly because treatment was instituted earlier. Trueand convalescent carriers were demonstrated and were regarded as the source ofthe disease. There was no evidence of contact infection.
Dobell28 examined 200 soldiers for E.histolytica as a routine measure and found 22, or 11 per cent, infected.Half of these denied any history of diarrhea or dysentery. Among these men, 4were undoubted contact carriers. Matthews and Smith,29 at theLiverpool School of Tropical Medicine, examined the stools of 4,062 dysenterypatients from the Western Front and found 12.1 per cent infected with the ameba.
The degree of infection in American troops both at home andabroad is indicated by the results of examination of returned soldiers atDebarkation Hospital No. 3 at New York City and of home-service men at the portof embarkation; 230 overseas men and 576 home-service men were thus examined.20Of the former, 12.8 per cent and of the latter 4.3 per cent were found toharbor E. histolytica. Very few of the men had dysenteric symptoms at thetime of examination. Later, an examination was conducted at the University ofCalifornia on students who had served as soldiers overseas. On this occasionrepeated examinations were possible and each of 154 men received an average of3.8 examinations. Of these men, 67 per cent were found positive for E. his-
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tolytica. The authors of the investigation conclude thatthe number of ameba carriers in the country must have been substantiallyincreased by the return of infected soldiers from overseas. These figuresconfirm the statement earlier made that the proportion of carriers of E.histolytica who manifest no clinical evidence of their condition is verylarge.
SYMPTOMATOLOGY AND PATHOLOGY
The clinical course of the average case of dysentery observedduring the World War naturally presented nothing different from the cases seenelsewhere; however, certain additions to our knowledge were made, eitherby American workers or by those of other armies, which deserve passing mention.
There is no discoverable record of anything to show theincubation period of bacillary dysentery. The onset was usually described assudden, with frequent bloody stools, prostration, tormina, and rectal tenesmus.Generally, the cases were mild or moderately severe in type. No cases weredescribed of the type resembling cholera-acutely toxic with death occurringwithout change in the number and character of the stools. Russell,21in his description of bacillary dysentery, states that the stool itself is quitecharacteristic and at the height of the disease is quite unlike the stool in anyother disease, not excluding amebic dysentery. It is small and consistsexclusively of blood and mucus, without a trace of fecal matter. Under themicroscope one sees red blood cells in enormous numbers, and epithelial cellsin masses; they are thrown off by the mucous membrane. These are often to berecognized as columnar epithelial cells, arranged like closely aligned picketson a fence, like a typical textbook picture. In addition, single epithelialcells in all stages of swelling, degeneration, and necrosis are seen. The singleswollen cells are often roundish and suggest at first quiescent ameb?, butthey do not possess the power of motion or the ability to send out pseudopodia.They may also be readily distinguished from amebic cysts by the large size anddifferent character of their nuclei. These various elements are embedded inmasses of glairy and stringy mucus. As the disease progresses and increases inseverity the character of the stool changes from that described above, theepithelial masses increase in size until one sees sloughs of large ulcers, oreven a pseudomembranous cast of the entire circumference of the gut. Under the microscope it isno longer possible to make out the structure of the epithelial cells, since theentire mass is coagulated and necrotic. The fluid part of the stool is no longerwatery, but serous, and dark from altered hemoglobin. Such stools are extremelyoffensive.
Bacillary dysentery usually runs an acute course, terminatingwith recovery in the course of a few days or weeks. A small percentage becomechronic or terminate fatally. Although not always true, this was the experienceof the Army during the World War. The case fatality was 2.17 and but 1 case wasdischarged for disability.
The chronic cases suffer from depression, emaciation, andrelapses. Jacob30 described a series of cases in which relapse occurredbetween the nineteenth and twenty-first day. Normal temperature preceded therelapse by one to three weeks. Intestinal symptoms were absent or stools weremuch like those of diarrhea; however, he isolated the Shiga and Flexner strainsfrom the stools
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during the relapse. Headache and joint pains were frequentlypresent. Pain along the colon is not an uncommon complaint. The proctoscopeoften reveals ulceration in the lower bowel.
PROGNOSIS
The prognosis of dysentery as observed during the World Waris very favorable. Of the 4,738 cases of all types of dysentery reported, but 73terminated fatally. This gives a case fatality of 1.54 per cent. Taking intoconsideration the admittedly large number of cases never reaching the hospital,or being entered upon the records, it is evident that even this low fatality isstated much too high. The prognosis appears to be decidedly less favorable inthe colored race than in the white. The case fatality in 220 cases in negroeswas 4.55 per cent, while of 3,547 cases in white enlisted men, but 1.48 per centdied. Again, the small number of cases in the colored, 220, with 8 deaths,introduces a large probable error and lessens the value of the comparison. Thesame considerations render the figures for case fatality of the various types ofdysentery of less value than would be the case had a larger proportion beenclassified etiologically in the reports. The case fatality for bacillary caseswas 2.17 per cent, while that of the entamebic cases was 1.29 per cent.
The entamebic cases were responsible for 85 of the 86dysenteric cases discharged for disability during the war. This is to beexpected on account of the chronic and relapsing character of this disease.Indeed, Craig27 recommended that the carriers of the entameba who are notreadily cleared up after a reasonable period of treatment should be dischargedfrom the service as a measure of protection to uninfected troops. Experience hasshown that such men can not stand the strain of active campaigning and soonsuffer relapses and become a burden rather than an asset to the service. Theaverage case of bacillary dysentery lost 19.6 days from duty; the amebic, 34.6.The unclassified dysenteries averaged 21.6 days lost, a figure much nearer thatof the bacillary group than that of the amebic cases. This confirms thededuction previously made that the vast majority of the unclassified cases wereof the bacillary type. Prognosis is of course modified by the promptness andefficacy of treatment and hence proved more favorable in the training camps inthe United States than was the case under battle conditions in France.
AUTOPSY FINDINGS
There are on file in the Surgeon General's Office theprotocols of 35 autopsies performed on dysentery cases. These are classified asfollows: Bacillary dysentery, 7 cases; amebic dysentery, 8 cases; mixedinfection, bacillary and amebic, 3 cases; dysentery with negative laboratoryfindings, 9 cases; complicated dysentery, 8 cases (pneumonia, 4; ulcerativeendocarditis, 2; influenza, 1; and tuberculosis, 1).
The autopsy findings in the bacillary cases were thosecommonly seen in this type of dysentery. In 6 of the 7 cases the heart showedacute myocarditis. In 5 cases occurring in the American Expeditionary Forces thediagnosis of bacillary dysentery was made by laboratory examination of thestools. Two cases were diagnosed a few days before death, the patients havingbeen admitted
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in extremis; one case dying from Flexner infection showedslight degenerative changes in the liver.
All of the amebic cases coming to autopsy showed abscess ofthe liver. The entameba was found in the pus of the abscess, in the intestinalulcers, or both. The lesions differed only in extent, and consisted ofulceration of the large bowel and in some cases the lower 2 feet of the ileum.The ulcers were generally very numerous and at times confluent, so aspractically to destroy the mucosa. No perforations were reported. The otherchanges found in these cases were secondary to perforation of abscesses into thepleural or peritoneal cavities. The liver abscesses were located in the convexportion of the right lobe of the liver in all cases but one, which involved theleft lobe only. The diagnosis had been made clinically in but one case; in 2others it was suspected while of the remaining 5, tuberculous peritonitis wasdiagnosed twice and appendicitis, lobar pneumonia, and bronchopneumonia onceeach.
From the necropsy standpoint, 8 of the 9 cases of dysenterycoming to examination without laboratory diagnosis were most probably bacillarydysentery. The location of the lesions, edema of the intestinal wall, areas ofulceration, pseudomembrane, and necrotic mucosa indicate the grounds on whichthis conclusion is based. In one case without laboratory findings, theconditions resembled those of the amebic type. Symptoms had persisted for fourmonths before death.
DIAGNOSIS
Under war conditions the diagnosis of a case of dysenterymust necessarily be made usually upon clinical grounds exclusively. Thedifferentiation of type in bacillary dysentery and even the distinction betweenbacillary and amebic cases require the use of laboratory equipment and trainedpersonnel. Therefore, under field conditions, the majority of cases werereported as "dysentery, unclassified." The occurrence of aconsiderable proportion of unclassifiable cases of clinical dysentery among thetroops in the camps in the United States shows that even under favorableconditions a specific diagnosis can not be arrived at in every case. Thedifficulties and uncertainties of diagnosis, and the resultant effects upon thestatistics have been touched upon incidentally in previous paragraphs.
The importance of early diagnosis has been indicated inrelation to the early institution of serum treatment. In the promptidentification of the bacillary forms all authorities agree that it is of firstimportance to secure a properly selected, fresh stool for bacteriologicalexamination. Kligler and Olitsky31 reported failures to isolateB. dysenteri? from cases of clinical bacillary dysentery and attribute thefailure to (1) improper selection of stool specimens for culture and (2) the useof unfavorable culture media. The stool selected should be one containing bloodand mucus, with little or no fecal matter. It is essential to plate the stooldirectly, or at least very shortly after it is evacuated. Experiments withartificial mixtures of Shiga bacilli and feces showed a 50 per cent reduction in4 hours, and from 85 to 90 per cent reduction in 24 hours when kept at roomtemperature. They recommended the use of a modified Endo-medium or the eosin-methyleneblue medium.
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A simple and satisfactory medium was devised in the centralmedical department laboratory, A. E. F., for the isolation of B. dysenteri? from stools.32It consists of:
Distilled water | 100 c.c. |
Agar | 15 gm. |
Peptone (difco) | 10 gm. |
Dipotassium phosphate | 4 gm. |
To each 100 c. c. is added:
Lactose, 20 per cent solution | 5 c.c. |
Glucose, 5 per cent solution | 1 c.c. |
Rosolic acid, 1 per cent in 90 per cent alcohol | 1 c.c. |
China blue, 0.5 per cent in water | 1 c.c. |
The hydrogen ion concentration of this medium is 7.4 to 7.5and it needs no adjustment. If the sugars are clean and white it needs nofiltration. The dysentery bacilli grow as luxuriantly on this as on any othermedium, and the lactose nonfermenters are readily recognized.
In addition to the precautions suggested by Kligler andOlitsky, the importance of securing, if possible, a stool for diagnosis early inthe course of the disease should not be overlooked. Recent work suggests thatthe bacteriophage developed in the intestine after the first few days of thedisease may be the inhibiting agent which causes failure to grow on the part ofthe infecting organism even when doubtless present in large numbers. With thedisappearance of the lytic agent during convalescence it is frequently againpossible to isolate the bacillus in large numbers.
The application of the agglutination test to the patient'sserum as a means of diagnosis has not resulted in great success. Specificagglutinins would not be expected to develop in much concentration until thedisease had progressed several days. This would militate against the use of thistest in early cases when diagnosis is most important. The American opinion isvoiced by Kligler,16 who remarks that it is a well-known fact thatagglutinins for the Flexner bacillus are present in fairly high concentration(1:50 or 1:75) in normal individuals. This is not true for Shiga agglutinins,which are rarely demonstrable in dilutions over 1:10. It would thus appear thatthe diagnosis of Shiga infection might be predicated upon a positiveagglutination in specific serum at a dilution of 1:20 or over, but that Flexnerinfection could only be diagnosed were the test positive at a dilution of atleast 1:100.
War experience has shown the fallacy of ascribing pathogenicproperties to bacteria isolated from the stools of dysentery patients merelybecause they conform in cultural characters to dysentery bacilli. An accuratediagnosis must be based both on cultural and specific serological criteria andsometimes even upon animal experimentation. Examination of fresh stools early inthe course of the attack, the use of suitable media, and skill in their use areessential for satisfactory results. A single negative examination is of littleor no value.
To our knowledge of the diagnosis of amebic dysentery littlewas added as the result of war experience. The importance of the differentiationbetween E. histolytica and E. nana, especially in the diagnosis ofcyst carriers, has been brought out earlier.
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The differential diagnosis between the bacillary and amebictypes of dysentery must be ultimately based upon laboratory findings. However,differences in the clinical appearance of the patient and in the general as wellas microscopic appearance of the stool may be valuable in making thisdifferentiation. The amebic patient, generally speaking, is less toxic, thetemperature is little if at all elevated, the number of stools, althoughincreased, is small as compared with the bacillary type, rarely exceeding 10 to14 per day, and the course of the disease is more prolonged. In bacillary casesof moderate to severe grade there is usually a sudden onset, the patient istoxic, temperature high, stools numerous-30 to 40, or more, in 24 hours. Hepresents the appearance of a very sick man and the disease is usually of shortduration. Descriptions of the microscopic characters of the stools in these twoconditions published during the war period have been superseded by the exactcytological diagnostic work of Willmore and Shearman,5 Manson-Bahr,6 andothers, which appear to have made the distinction easily possible on microscopicgrounds.
TREATMENT
This is a subject necessarily treated differently for thedifferent types of the disease. So, too, the treatment of the acute, initialattack must differ from that of the chronic forms in cases in which the diseaseobtains a prolonged hold. This latter unfortunate happening is usually theresult of delay in starting treatment and is characterized pathologically by anulcerated condition of the intestine even in the bacillary cases, andsymptomatically by intermittent diarrhea, usually without much blood or mucous,but showing pus, anemia, and varying degrees of prostration. There is no recordof this type of disease having attracted attention in the American forces duringthe World War although presenting a serious problem to some of our Allies,especially in the East. Consequently only the treatment of the acute attack willbe considered here.
The most important thing in the treatment of acute bacillarydysentery is the establishment of at least a probable diagnosis. In epidemictimes this is usually evident, although when both bacillary and amebic dysenteryare prevalent the differentiation is important. The treatment should be alonglines both specific and symptomatic. The specific treatment of bacillarydysentery consists of the administration of a reliable polyvalent antidysenteric serum in a sufficient dosage and as early as possible. Thistreatment has not been used extensively in the United States, possibly becausesevere clinical forms of dysentery are not common here and possibly because thetreatment has not habitually been administered early enough on account of delayfor the purpose of obtaining a bacteriological confirmation of the diagnosisbefore the administration of serum.
According to Russell21 the serum is best given in largedoses following Shiga's rule, 1 dose of 10 c. c. in mild cases, 2 such dosesat intervals of 6 hours, in cases of moderate severity, and in severe cases 10c. c. twice a day for 2 or 3 days. The tendency seems to be to increase thedosage, and even a dose of 100 c. c. daily has been given to severe cases withapparent benefit.
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The British believe33 that the value of the specificserum has been established and that the sooner it is administered the better.They recommend an initial dose of from 20 c. c. to 60 c. c. Bahr and Young34recommend administration of the serum in all doubtful cases while awaitingthe results of laboratory examination. They believe that the benefits obtainedby prompt administration outweigh any objections to the treatment of anoccasional nonbacillary case and state that it does not act deleteriously in anycase, irrespective of the nature of the disease. In a memorandum on medicaldiseases in the tropical and subtropical war areas, the British state that theaction of antidysenteric serum is often remarkable, as much as 400 c. c. havingbeen given in severe cases, and (apparently) it has been the means of saving thepatients.35 The French used serotherapy extensively but withvarying results.26 Among the Germans, Schittenhelm36remarksthat, as in the case of diphtheria, it should be given as soon as possible. Herecommends the intramuscular route as more rapidly effective. The dose used bythe Germans was larger than that used by the Americans.
The patient should be confined to his bed, and the use of thebedpan enforced. The diet should be nonirritating and at first liquid, using thestrained types of diet which leave little residue. An important point in thenonspecific treatment is the clearing of the bowel by means of salines. A methodfor accomplishing this is as follows: A dose of 20 c. c. of saturated solutionof magnesium sulphate is given every four hours, each dose followed an hourlater by 10 drops of aromatic sulphuric acid in water. This results at first inan increase in the number of stools, but within two days they are greatlyreduced in number, pain becomes less, and general improvement is noted.
The following saline treatment was recommended by Balfour:33
Rx
Sodium sulphate | gr. lx. |
Acid. sulph. aromat | m. xv. |
Tr. zingiberi | m. v. |
Aq. menth. pip | oz. ss. |
M.
This mixture above should be administered every 2, 3, or 4hours until the stools become watery. It is claimed to be better than magnesiumsulphate. Bismuth subnitrate, 60 grains, and salol, 3 grains, every 6 hours areuseful in the later stages. In very severe cases, drained by the constantevacuations, Balfour recommends the Rogers cholera treatment,33 theintravenous administration of hypertonic salt solution to restore blood volumeand prevent acidosis. Ipecac and its alkaloid are without value in bacillarydysentery and opium and its derivatives are probably harmful by forciblychecking the number of evacuations and retaining within the intestine the toxinof the invading organisms.d
dWith the postwar development of the cytological method of diagnosis in the dysenteries, it has become possible in the great majority of cases to render an opinion as to thetype of dysentery, bacillary or amebic, within a few minutes after a stool specimen has been received in the laboratory. The useof this aid places the early administration of the serum upon a sound scientific basis; and judging from our experience inthe Philippine Islands, a majority of cases could be diagnosed and treated with success in a medical echelon very close tothe front, and need never reach the larger hospitals.
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Little new developed from war experience in the treatment ofacute amebic dysentery, although much work was done along this line. It resolvesitself into the effective administration of emetine. First suggested as a remedyfor dysentery in 1829 by Bardsley37 of Manchester, it was found to be amebacidalby Vedder38 of the United States Army (1910-11), and its use in amebicdysentery was established in 1912 by Sir Leonard Rogers.39 Theroutine treatment consists in the daily administration of 1 grain of thealkaloid subcutaneously for a period of 12 days. Such a course usually causes arapid improvement with cessation of dysenteric symptoms, but it can not berelied upon to cure the disease in the sense of completely removing theinfecting ameb?. It is necessary to keep the patient in bed during such acourse of emetine, not only for the purpose of controlling the diet, but also asa protection to the heart. Dale40 showed thatemetine in large doses iscumulative in its action, and that neuritis has followed its use. Two fatalcases of emetine poisoning were reported in 1916 from Base Hospital No. 2, atFort Bliss, Tex.41 The possible deleterious effect onthe heart is pointed outby Wenyon and O'Conner, whose report describes two cases.
Attempts to develop a form of emetine administration moreeffective in clearing up the infection than the alkaloid alone led tointroduction by Du Mez42 of the double iodide of emetine and bismuthwhich contains 58 per cent of iodine, 12 per cent bismuth, and 29 per centemetine. The alkaloid is gradually liberated under the action of the alkalinesecretions of the intestine. It is less emetic in its action than is emetinealone, but may cause nausea in some instances. This may be mitigated by theprevious administration of 10 to 12 drops of the tincture of opium, preferablyafter the patient has retired for the night and after a light meal. Under thistreatment it does not appear to be necessary to confine the patient to his bed.The dose is 3 grains daily, preferably in a single dose rather than in divideddoses. The treatment is continued for 12 days. This treatment is usuallyregarded as less effective in the removal of the symptoms of the acute statethan is the subcutaneous emetine treatment, but is more effective in clearing upthe carriers.
The use of emetine bismuth iodide in conjunction with thehypodermic injections of emetine would seem to be beneficial in thatconvalescence is established earlier and patients are less apt to becomecarriers.43 But it can not be considered as a substitute for emetine,as attempts to treat acute cases with it alone ended in failure until emetinewas used in addition.
Patients may be completely cured by the emetine treatment,but probably two-thirds of the cases, though completely relieved from theirsymptoms, still harbor the organism, as shown by the excretion of cysts. Suchpatients are almost sure to suffer relapse at some later date and of course arethe main source of infection of others. The clearing up of carriers has thusbecome a major problem of the treatment. Wenyon and O'Conner18 advisedthe combined oral and hypodermic use of emetine hydrochloride in the treatmentof carriers. One grain of the drug is given hypodermically in the morning dailyfor 12 days, and one-half grain in a keratin-coated tabloid is given by moutheach evening. They reported 30 carrier cases treated by this method with norelapses. In 37 carriers treated by the hypodermic method alone, there were 10relapses, and in 5
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the drug failed to act. Of six cases treated orally, halfshowed either no reaction to the drug or suffered relapse. Jepps and Meakins44concluded that emetine bismuth iodide cured 95 per cent of E. histolytica carriers,and that the best method of administration is in the form of a loose powdercontained in a cachet, in daily doses of 3 grains. At least 36 grains should begiven in all. The Medical Research Council45 reports on the resultsof treatment of 155 E. histolytica carriers with emetine bismuth iodidein various forms, and in doses of 3 grains daily for 12 or more consecutivedays. A single first course of treatment cured 90 per cent of their cases. Whenthey remain uncured after such treatment, the best method of retreatment is togive them a double course of the drug; that is, 3 grains daily for 24 days. Suchtreatment has not cured every case, but there is no evidence that those who arenot curable by such means constitute more than 5 per cent of all carriers of E.histolytica.
In conclusion, it may be said that emetine hydrochloride,alone or in conjunction with emetine bismuth iodide, was the preferred form ofspecific therapy for amebic dysentery during the World War, while the use of thedouble salt gave the best results in the treatment of carriers.
PREVENTIVE MEASURES
The preventive measures used during the World War fall intotwo classes, the general and the specific measures. The former comprise nothingthat was not previously known, but instructions issued by the War Department onthe subject and examples of conditions under which the troops had to operate areof value. Some such examples have been given already.
Of the general preventive measures the early diagnosis andisolation of the sick, discovery, isolation and treatment of carriers,destruction of flies and prevention of fly breeding, safe-guarding of watersupplies, precautions to prevent contamination of food, and the proper disposalof feces were the methods on which we depended for the limitation of thedysenteries as well as of the typhoid group and other intestinal infections. In1917 the Surgeon General issued the following instructions relative to thecausation and prevention of the dysenteries:46
Dysentery-Causes and natur -Dysentery, orinflammation of the large intestine, is caused by two classes of microorganisms,an ameba and certain bacteria. The former gives rise to amebic, the latter tobacillary dysentery. The bacterial or bacillary form of dysentery is more widelydistributed over the world than the amebic. While the former is found in allclimates, the latter is chiefly restricted to warm countries. But personssuffering from amebic dysentery may carry the disease from a warm to a coldclimate.
Sources of infection - The ameb? and bacilli whichcause dysentery are contained in the intestinal contents and are dischargedwith them. They are, therefore, subject to the same manner of distribution asare the typhoid bacilli, and the preventive measures to be employed areidentical with those employed in typhoid fever. It may be well, however, toemphasize the common occurrence of carriers of dysentery bacilli and ameb?among exposed and recovered cases and the necessity of enforcing habits ofpersonal cleanliness and other related measures to control the disease.
Diarrhea, etc. -In addition to dysentery, slighter andnondysenteric forms of intestinal trouble are more or less common. As theresults of chill or indiscretion in diet, diarrhea, griping, and even bloodystools may arise. But any case of persistent diarrhea in which blood and mucusare being discharged should be regarded as suspicious and submitted to a
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laboratory examination in order to determine whether it maybe dysentery. The ameb? are searched for by direct microscopic examination; thebacilli may be obtained in culture, or an agglutination test made with thepatient's blood to determine their presence.
The intestinal group of diseases -(a) Typhoid andparatyphoid fever, cholera, with amebic and bacillary dysentery form a group ofintestinal infections in which the causative microorganisms are discharged withthe excreta and gain access to healthy persons through the mouth. The generalprinciples of their prevention are practically identical. The first effortshould be made to destroy the infectious agents at their source, namely, in thedischarges from the intestine. The next effort should be to control the waterand food supply and the personal habits of the men, so that any of themicroorganisms which escape destruction may not find their way into thedigestive tract in a living condition.
(b) No man should be employed as cook or handler of foodor water who is a carrier of B. typhosus, B. paratyphosus, A or B, orcysts of Entameba histolytica.
(c) Stools of all cooks and food handlers (includinghandlers of water and drivers of water and ice wagons) will be examined fortyphoid, paratyphoid A and B, and dysentery bacilli, and for cysts of Entamebahistolytica. In the case of enlisted men, notation of positive findingsshould be made upon the service record.
As missed and mild cases are undoubtedly responsible for muchspread of infection, it is advisable, when military considerations permit, tohospitalize, at least for a brief period, as large a proportion of these casesas possible to permit the disinfection of dejecta, clothing, linen, etc. Such ameasure is particularly practicable in the case of troops not actively engagedwith the enemy.
Specific vaccination against the dysenteries, using apolyvalent vaccine prepared along the same general lines as is that against thetyphoid group, had been practiced to some extent before the war. According toRussell,21 such measures are theoretically correct and under suitableconditions should give good results. Antidysenteric vaccination was not used asa routine measure in the Army during the World War and practical experienceconfirmed the judgment that it is rarely necessary. Dysentery was not, exceptfor very brief periods, an important cause of disability in the areas occupiedby our troops. The main objection to its routine use, unless special conditionsdemand it, has been the severe character of the reaction induced by effectivedoses of the vaccine. To overcome this difficulty several expedients were tried.One was the introduction of sensitized vaccines by Boehnke and Elkeles47 in1915 and by Gibson48 in 1917. The Boehnke prophylactic was prepared for theGerman Army by adding the B. dysenteri? toxin and antitoxin in varyingproportions to an emulsion of dysentery bacilli of various types. This wastermed "dysbakta." It is doubtful according to Russell,21 whetherthe advantages of such a mixture are marked enough to justify the use ofrepeated small doses of the contained horse serum. Dopter49 and Besredka50attempted to produce vaccines which could be administered orally. Underexperimental conditions they attained some degree of success and the applicationof their methods to the human is still under trial. So far, the degree ofsuccess attained has not been such as to make oral vaccination the method ofchoice.
The application of the lipovaccine to the prevention ofdysentery was attempted. Officers at the Army Medical School51produced such a vaccine. It contained 2,000,000,000 Shiga bacilli, with the samenumber of the Flexner and of the "Y" types, per cubic centimeter. Thelocal and general reaction
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to a dose of 1 c.c. of this vaccine was said to be no greaterthan that induced by the regular saline triple typhoid vaccine. Olitsky52 confirmedthe safety and practicability of producing a vaccine by the emulsion of varioustypes of dysentery bacilli in oil. The method is still in its experimentalstage. A main difficulty appears to be the attainment of effective sterilizationof the vaccine.
Against amebic dysentery the same general hygienic measuresas have proven of value against the bacillary form should be effective. Theprophylactic use of emetine might be of value in situations where a highincidence of the disease was to be expected. The French under these conditionsused 4 or 5 grains of emetine hydrochloride dissolved in tincture of opium inthe proportion of 1 to 15. Of this mixture, 8 to 10 drops were added to a cup ofstrong tea and taken each night. The method is comparable to the prophylacticadministration of quinine in malaria and might serve an equally useful purpose.
NONSPECIFIC DIARRHEA, ENTERITIS, AND COLITIS
The affections included in this heterogeneous group ofgenerally mild diarrheal affections were classified under one heading or theother, according to the individual preference of the reporting officer. If hispreference was for a symptomatic diagnosis, the case was called diarrhea; if fora pathologic or anatomic designation, it became enteritis or colitis on therecords.
The occurrence of these diseases is shown in the basic tablefrom which most of our figures have been drawn-Table 49. The totals shown inTable 49 for the group as a whole include the dysentery cases as well, but thepercentage of the total cases represented by the dysenteries as reported is sosmall, about five, that their inclusion is without effect upon the relativeposition of the different personnel groups when the latter are compared.Therefore it would be a work of supererogation to go again into the effect ofgeographical location of troops, race, etc., in regard to the incidence of thesediseases. What has already been said with regard to the group as a whole isequally true of the nonspecific diarrheas and enterocolitis.
In the discussion of the true dysenteries it was brought outthat many such cases were undoubtedly reported under the nonspecific headingsfor various reasons which were there discussed. It seems probable that most ofthe fatality associated with the conditions now under discussion was the resultof this inclusion among them of cases of true dysentery. Another possibility isthat a certain number of chronic cases were also included among them. Most ofsuch cases were probably classified in the tables under the heading"Miscellaneous diseases of the intestinal tract," but others couldeasily have been reported as "chronic diarrhea" or "chroniccolitis" and so have become included in our figures. Such chronic caseswould have tended to increase the fatality of the group, its proportion ofdischarges for disability, and the number of days lost from duty over whatwould have been the case had only acute cases been reported.
In spite of such probable inclusions, the type of diseaserepresented was evidently mild, as shown by the average duration of the cases.The figures show that these cases in the United States occasioned only fromthree to five days' loss of time per case. In Europe, owing to the inclusionof a considerable
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proportion of the more severe dysenteries, and to the loss oftime occasioned by the delays in reaching hospitals, the average time lost waslonger. It is evident, however, from the descriptions of epidemics in the battlezones that the great majority of the diarrhea cases were not severe enough to goregularly on sick report.
No specific statement of the etiology of these milderdiarrheas as distinct from the dysenteries is possible. Dietary indiscretions,or more frequently the character and condition of the only food available, havebeen blamed in some instances. However, in the latter case the actual cause ofthe trouble may with more probability be considered to have been bacterialinfective agents contained in the food. The same may be said of the drinking ofpolluted water. Such water probably always contains the germs of dysentery ortyphoid or paratyphoid fevers, and the result of its use would naturally be themixed type of epidemic seen in France.
The monthly incidence of these conditions as shown in ChartXXXVI indicates that in the United States, where the curves were not broken byperiods of military activity, there is a definite seasonal increase ofincidence, culminating in July or August. At this season air temperature rendersalmost any food exposed to infection a suitable culture medium for bacteria ofthe types under consideration, and the large number of flies usually to be seenabout food in connection with the filthy feeding and breeding habits of thisinsect provides an easy explanation of the method in which infection reaches thefood.
By no means the last word has been said on the subject of theetiology of diarrheal infections. It is entirely possible that many mild attackswhich occur more or less typically in epidemic form in the civilian populationhave a specific etiology at present entirely unknown. That most cases, howevermild, owe their inception to some infective agent, whatever it be, may beconsidered to be proven by the close correlation between the incidence of thesemilder diseases with those of known bacterial etiology. Those measures ofsanitation which suffice to limit typhoid, cholera, and dysentery, serve also toreduce the incidence of the milder diarrheas. When conditions permit effectivesanitary discipline all these conditions are reduced almost to the vanishingpoint.
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(1) Medical and Surgical History of the War of the Rebellion, Part Second, Medical Volume, Government Printing Office, Washington, D. C., 1879, 1.
(2) Report of the division of sanitation and inspection, Chief Surgeon's Office, A. E. F., by Col. Haven Emerson, M. C., May 31, 1919, to the Surgeon General, U. S. Army. On file, Historical Division, S. G. O.
(3) Annual Report of the Surgeon General, U. S. Army, 1919, Vol. 1541.
(4) Report on diarrheal diseases, Base Hospital No. 89, A. E.F., made by the commanding officer. On file, S. G. O., 710-1 (old), Dysentery.
(5) Willmore, J. G., and Shearman, C. H.: On the Differential Diagnosis of the Dysenteries. The Lancet, London, August 17, 1918, ii, 200.
(6) Manson-Bahr, P.: The Commoner Complications of Bacillary Dysentery in Military Practice. The British Medical Journal, London, June 12, 1920, i, 791.
(7) Hanghwout, F. G.: Protozoologic and Clinical Studies on the Treatment of Protozoal Dysentery with Benzoate. Archives of Internal Medicine, Chicago, 1919, xxiv, No. 4, 383.
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(8) Telegram, August 6-7, 1918, from "Wright" to Director of Laboratories at Dijon. On file, Historical Division, S. G. O.
(9) Letter from Major Hans Zinsser, M. R. C., to the Director of Laboratories and Infectious Diseases, A. E. F., August 19, 1918. Subject: Epidemic of diarrhea in the area occupied by the Paris group of the First Army, A. E. F. On file, Historical Division, S. G. O.
(10) Weekly Bulletin of Diseases, No. 20, Chief Surgeon's Office, August 26, 1918, A. E. F. On file, Historical Division, S. G. O.
(11) Spencer, H. R.: Report on an investigation of an epidemic of diarrhea, among the personnel of the 355th Infantry at Grand, July 27, 1918. On file, Historical Division, S. G. O.
(12) Letter from Harry C. Travelbee, 1st Lieut., and Lawrence A. Kohn, 1st. Lieut., to the Chief Surgeon, Paris group, A. E. F., August 28, 1918. Subject: Report of bacteriological findings in so-called dysentery cases investigated August 12, 1918, to August 26, 1918. On file, Historical Division, S. G. O.
(13) Letter from R. M. Taylor, Capt., M. C., to the Director of Laboratories, Base Section No. 1, A. E. F., Subdivision, Department of Infectious Diseases, August 26, 1918. Subject: Diarrhea and dysentery. On file, Historical Division, S. G. O.
(14) Letter from J. E. Walker, M. C., to Chief Surgeon, A. E. F., August 31, 1918. Subject: Report on an investigation of a dysentery outbreak at Romorantin and Gievres. On file, Historical Division, S. G. O.
(15) Letter from Lawrence A. Kohn, 1st. Lieut., Sanitary Corps, to the commanding officer, Central Medical Department Laboratory, October 9, 1918. Subject: Final report of investigation of epidemic of dysentery in the 37th Division, A. E. F., August 28, 1918, to September 4, 1918. On file, Historical Division, S. G. O.
(16) Kligler, I. J.: Report on the nature of a supposedly atypical dysentery bacillus, embarkation hospital, Newport News, Va., September, 1918. On file, Historical Division, S. G. O.
(17) Martin, C. J., and Williams, F. E.: The Chance of Recovering Dysentery Bacilli from the Stools According to the Time Elapsing Since the Onset of the Disease. British Medical Journal, London, 1918, i, 447.
(18) Wenyon, C. M., and O'Connor, F. W.: An Inquiry into Some Problems Affecting the Spread and Incidence of Intestinal Protozoal Infections of British Troops and Natives in Egypt, with Special Reference to the Carrier Question, Diagnosis and Treatment of Amoebic Dysentery, and an Account of Three new Human Intestinal Protozoa. Journal of the Royal Army Medical Corps, London, 1917, xxviii, No. 2, 151, No. 3, 346, No. 4, 461.
(19) Jepps, M. W., and Dobell, C.: Dientamoeba fragilis, n. g., n. sp., a new Intestinal Amoeba from Man. Parasitology, Cambridge, England, 1918, x, No. 3, 352.
(20) Kofoid, C. A.; Kornhauser, S. I.; and Plate, J. F.: Intestinal Parasites in Overseas and Home Service Troops of the U. S. Army. The Journal of the American Medical Association, Chicago, 1919, lxxii, No. 24, 1721.
Kofoid, C. A., and Swezy, O.: On the Prevalence of Carriers of Endamoba dysenteri? among Soldiers Returned from Overseas Service. New Orleans Medical and Surgical Journal, New Orleans, 1920-21, lxxiii, No. 1, 4.
Kofoid, C. A.; Kornhauser, S. I.; and Swezy, O.: Criterions for Distinguishing the Endamoba of Amobiasis from Other Organisms. Archives of Internal Medicine, Chicago, 1919, xxiv, No. 1, 35.
(21) Russell, F. F.: Bacillary Dysentery. Tice's Practice of Medicine. W. F. Prior Co., Hagerstown, Md., 1924, iv, 375.
(22) Nichols, Henry J.: Carriers in Infectious Diseases. Williams & Wilkins Co., Baltimore, 1922, 64.
(23) Arkwright, J. A.; Yorke, W.; Priestley, O. H.; and Gilmore, W.: Examination of Fifty Dysentery Convalescents for Carriers. Journal of the Royal Army Medical Corps, London, 1916, xxvii, No. 6, 755.
(24) Kennedy, A. M., and Rosewarne, D. D.: Observations upon Dysentery Carriers. The British Medical Journal, London, 1916, ii, 863.
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(25) Fletcher, Wm., and Mackinnon, D. L.: A Contribution to the Study of Chronicity in Dysentery Carriers. National Health Insurance, Special Report Series, No. 29, Medical Research Committee, London, 1919, 5.
(26) Dopter, M.: Les Maladies Infectieuses pendant la Guerre. Librairie F?lix Alcan, Paris, 1921, 119.
(27) Craig, C. F.: The Occurrence of Endamoebic Dysentery its the Troops Serving in the El Paso District from July, 1916, to December, 1916. The Military Surgeon, Washington, 1917, xl, No. 3, 286 and 432.
(28) Dobell, C.: Incidence and Treatment of Entamoba histolytica Infection at Walton Hospital. The British Medical Journal, London, 1916, ii, 612.
(29) Matthews, J. R., and Smith, A M.: The Intestinal Protozoal Infections Among Convalescent Dysenteries examined at the Liverpool School of Tropical Medicine. Annals of Tropical Medicine and Parasitology. London, 1919, xiii, No. 1, 83.
(30) Jacob, L.: Klinischie Beobachtungen bei Bazillenruhr. Zeitschrift fuer Hygiene und Infectionskrankheiten, Leipzig, 1917, lxxxiii, 467.
(31) Kligler, I. J., and Olitsky, P. K.: Method for the Isolation and Rapid Identification of Dysenteric Bacilli. The Journal of the American Medical Association, Chicago, 1918, lxxi, No. 26, 2126.
(32) Levine, Max: Dysentery and Allied Bacilli. Journal of Infectious Diseases, Chicago, 1920, xxvii, 31.
(33) Balfour, A.: Notes on the Treatment of Diarrhea and Dysentery Issued by the Advisory Committee for the Prevention of Epidemic Diseases in the Mediterranean Expeditionary Force. Journal of the Royal Army Medical Corps, London, 1915, xxv, No. 5, 473.
(34) Bahr, P. H., and Young, J.: War Experiences in Dysentery, 1915-1918. Journal of the Royal Army Medical Corps, London, 1919, xxxii, No. 4, 268.
(35) Memoranda on Medical Diseases in the Tropical and Subtropical War Areas, 1919. His Majesty's Stationery Office, London, 67.
(36) Schittenhelm: Handbuch der Aerztlichen Erfahrungen im Weltkriege, 1914-1918. Innere Medizin. Ambrosius Barth, Leizig, 1921, Band iii, 136.
(37) Bardsley, J. L.: Hospital Facts and Observations. Burgess and Hill, London, 1830, 148.
(38) Vedder, E. B.: A Preliminary Account of some Experiments Undertaken to test the Efficacy of the Ipecac Treatment of Dysentery. Bulletin of Manila Medical Society, Manila, March, 1911.
(39) Rogers, L.: The Rapid Cure of Amoebic Dysentery and Hepatitis by Hyperdermic Injections of Soluble Salts of Emetine. The British Medical Journal, London, June 22, 1912, i, 1424.
(40) Dale, H. H.: A Preliminary Note on Chronic Poisoning by Emetine. The British Medical Journal, London 1915, ii, 895.
(41) Johnson, H. H., and Murphy, J. A.: The Toxic Effect of Emetine Hydrochloride. The Military Surgeon, Washington, 1917, xl, 58.
(42) Du Mez, A. G.: Two Compounds of Emetin which may be of service in the treatment of Entamoebiasis. The Philippine Journal of Science, Manila, 1915, x, No. 1, 72.
(43) Lambert, A. C.: The Treatment of Amoebic Dysentery with Emetine and Bismuth Iodide. British Medical Journal, London, 1918, i, 116.
(44) Jepps, M. W., and Meakins, J. C.: Detection and Treatment with Emetine Bismuth Iodide of Amoebic Dysentery Carriers among Cases of Irritable Heart. The British Medical Journal, London 1917, ii, 645.
(45) Great Britain, National Health Insurance Joint Committee. Medical Research Committee. A Contribution to the Study of Chronicity in Dysentery Carriers. His Majesty's Stationery Office, London, 1919, No. 29.
(46) Special Regulations No. 28, August 10, 1917, War Department.
Annual Report of the Surgeon General, U. S. Army, 1919, Vol. II, 1585.
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(47) Boehnke and Elkeles: Ruhr schuetzimpfungen mit Dysbakta. Muenchener Medizinische Wochenschrift, Muenchen, 1918, lxv, Part 2, No. 29, 784.
(48) Gibson, H. G.: A New Method of Preparation of a Vaccine against Bacillary Dysentery which abolishes severe local Reaction. Also Experiments with this Vaccine on Animals and Man. Journal of the Royal Army Medical Corps, London, 1917, xxviii, No. 6, 615.
(49) Dopter, Ch.: Vaccination antidysent?rique experimentale par les voies digestives. Comptes Rendus Hebdomadaires des S?ances et M?moires de la Soci?t? de Biologie, Paris, 1908, i, 868.
(50) Besredka, A.: Du m?canisme de l'infection dysent?rique de la vaccination contre la dysent?rie par la voie buccale et de la nature de l'immunit? antidysent?rique. Annales de l'Institut Pasteur, Paris, 1919, xxxiii, No. 5, 301.
-- Reproduction des infections paratyphique et typhique. Sensibilisation au moyen de la bile. Ibid. No. 8, 557.
(51) Whitmore, E. R.; Fennel, E. A.; and Petersen, W. F.: An Experimental Investigation of Lipovaccines. The Journal of the American Medical Association, Chicago, 1918, lxx, No. 7, 427.
(52) Olitsky, P. K.: An Experimental Study of Vaccination against Bacilli Dysenteriae. The Journal of Experimental Medicine, New York, 1918, xxviii, 69.
