The number of deaths was not great following measles during the SpanishAmerican War and Philippine insurrection. The peak, as shown on Chart XLV, was reached in March, 1902.

The admission rate for white and colored troops combined for the entire period of the Civil War, from May, 1861, to June, 1866, was 32.22 per thousand per annum; the death rate was 2.02. During the Spanish-American War and Philippine insurrection, from May, 1898, through June, 1902, the admission and death ratios per thousand strength were 26.06 and 0.32, respectively. For the World War, based on occurrence in the United States and Europe only and from April, 1917, to and including December, 1919, the admission ratio was 25.28 and death ratio 0.63 per thousand per annum. It may be inferred, then, that measles was better controlled during the period of the World War as a whole than during the other two wars under consideration, and while the death rate was twice as high as that for the Spanish-American War and Philippine insurrection, it was less than one-third as high as the corresponding rate during the Civil War.

DURING THE WORLD WAR

Discussions which follow are based, generally, upon the primary admissions. For the total Army the admission, death, and noneffective ratios were 23.79, 0.57, and 1.25 per thousand per annum, respectively. American officers and enlisted men contributed 96,817 admissions, 2,367 deaths, and a loss of time. from duty amounting to 1,864,477 days. This occurrence was among the total mean annual strength of approximately 4,000,000 men. Officers, as shown in Table 65, with an aggregate strength of 206,382, contributed 974 admissions and 3 deaths, the loss of time from duty amounted to 12,015 days. The noneffective ratio was 0.16 per thousand per annum. The admission and death ratios were, respectively, 4.72 and 0.01 per thousand, the lowest in the Army where large bodies of troops were concerned. This is probably accounted for by the difference in age and living conditions among officers as compared with enlisted men. Among American enlisted men there were 95,843 primary admissions, with 2,364 deaths. The admission and death rates were 24.66 and 0.61 per thousand strength, respectively, and the loss of some 1,800,000 days, with a noneffective ratio of 1.31 is credited to them. Enlisted native troops, serving in their home territory, had 1,408 primary admissions among a total of a mean annual strength amounting to 36,022. There were three deaths with admission and death ratios of 39.08 and 0.08 per thousand per annum, respectively. From the above it is seen that the highest admission ratios were among native troops, and the lowest among American officers.

It was the opinion of medical officers that deaths did not follow uncomplicated measles, but were due to complications and concurrent diseases. It was the practice in the statistical division of the Surgeon General's Office, as noted elsewhere (p. 5), to charge all subsequent developments to the primary cause of admission to sick report. This accounts for the deaths, permanent disability, and much of the time lost from duty credited to measles in this chapter. Therefore, for a comprehensive understanding of this chapter the reader should take the method of computation into consideration.

MEASLES (ALL)

CIVIL, SPANISH-AMER. & PHIL. INSUR., AND WORLD WARS WHITE AND COLORED ENLISTED MEN, U. S. ARMY BY MONTHS

CHART XLV

TABLE 65.-Measles. Admissions, deaths, discharges for disability, and days lost, by countries of occurrence, officers and enlisted men, United States Army, April 1, 1917, to December 31, Absolute numbers and rates per 1,000

1919.

OCCURRENCE IN THE UNITED STATES

More than eight-tenths of the primary admissions were among troops serving in the United States. (See Table 65.) There were 85,398 such admissions among the troops serving at home and in Alaska. In so far as Alaska is concerned, for all practical purposes the number of measles admissions there was so small it need not be considered. The total annual mean strength of the Army in the United States was about two and a quarter million men, and among these there were 1,987 deaths. The admission and death ratios were 38.20 and 0.89 per thousand per annum, respectively. The loss of time from duty was considerable and amounted to 1,600,798 days, with a noneffective ratio of 1.96 per thousand. Enlisted men serving in home territory contributed 145 of the 149 cases discharged for disability. There were 84,585 primary admissions for measles among enlisted men, 80,546 of which were among white enlisted men. The annual admission ratio for the total enlisted was 40.06 per thousand strength, the highest experienced by these troops due to measles in any country in which they served. Of the total 2,370 deaths charged to primary admissions, 1,986 occurred among the enlisted men serving at home. The death ratio was 0.94 per thousand. One and a half million days were lost from duty, with the highest noneffective ratio that occurred among American troops serving in any country during the World War. It was 2.07 per thousand strength.

RELATION OF OCCURRENCE TO MOBILIZATION

7

Apparently no disease was more closely allied to mobilization than was measles. This is shown quite clearly in Chart XLVI. During the fall and early winter of 1917, when mobilization camps were being organized, barracks and tents were overcrowded and inadequately heated, and it was impossible to supply the men with sufficient warm clothing. These adverse conditions were augmented by an unusually early and severe winter. The draft brought large numbers of persons together from all walks of life and from every environment. The inducted men were principally young adults and included not only the generally immune city boy, but also vast numbers of rural lads who had never before been exposed to the infection.

The influence of introducing large numbers of nonimmunes into the camps during the war is shown by Chart XLVI, which depicts the comparative trend between mobilization and measles. In November, 1918, the drafting of men ceased and recruiting was not resumed until March of the following year. This, of course, tended promptly to bring the measles rate down to a low level. Additional factors which had a tendency to reduce the occurrence of measles in the Army below the 1917 peak were the better housing, clothing, isolation, and heating facilities which became available in 1918. The occurrence, however, ran generally parallel with mobilization. Length of service also, influenced occurrence; in more than two-thirds of the cases the men had had three months' service or less. In other words, the disease developed during the early camp service of the recruit.

OCCURRENCE BY CAMPS

Analysis by camps of occurrence in the United States shows great difference in extent to which this disease prevailed. It varied from 1.19 per thousand strength at Camp Syracuse, N. Y., and 7.27 at Camp Dix, N. J., to 164.67 per thousand at Camp Pike, Ark., among white enlisted men. (Table 66.) The location of the camp played no determining rôle; it was largely a matter of

MEASLES (ALL) AND MOBILIZATION

ADMISSIONS & NO. OF ENL. MEN MOBILIZED, U. S.

COMPARATIVE TREND BY MO., APRIL, 1917-DEC., 1919

LOGARITHMIC SCALE

ABSOLUTE NUMBERS

1.000.000

one camp drawing a higher percentage of immunes or nonimmunes than another. The maximum occurrence was attributed to troops from the southeastern portion of the country (Chart XLVII). From a study of the population of the eastern portion of the United States, one is justified in saying that the northeastern section is thickly settled while the southeastern is sparsely settled. In other words, the bulk of the population in the former have lived in cities and