MICROCOCCUS INTRACELLULARIS MENINGIT1DIS ( 537 



Canadian troops on Salisbury Plains. The increase of cases among 

 these troops took place in February, 1915, and after this time the 

 disease began to appear in the overseas expeditionary troops, al- 

 though among these no extensive epidemic occurred at any time. 

 Among American troops the disease was most prevalent in 1917 

 and 1918 among the troops gathered in the cantonments in the 

 United States. According to the epidemiological studies of Vaughan ( 

 and Palmer 4 ' 5 in the camps in 1918, meningitis showed "of all dis- 

 eases, the greatest excess over the disease in civilian communities.'* 

 Vaughan estimates that meningitis was forty-times as frequent in 

 the Army as in civilian life. The highest morbidity occurred at 

 Camp Jackson where it reached a rate of 25.1 per thousand, and a 

 death rate of 7.05. Next to pneumonia, it was the most serious disease 

 occurring in the camps. In the Surgeon General's report for 1918, 

 the disease stood fifth as a cause of death for enlisted men in the 

 United States and Europe, with a case mortality of 34.8 per cent. 



During the Army epidemics there was a definite racial difference 

 in that, according to Surgeon General Ireland's report, the admission 

 rate for colored troops in the United States was 2.44, whereas, it 

 was only 1.2 for whites, and the death rate for colored troops was 

 0.98 against 0.41 for whites. 



As to seasonal prevalence, meningitis usually develops in the 

 late autumn and winter months, the largest case rates being coin- 

 cident with the cold and wet weather, when a basic catarrhal inflam- 

 mation of the upper respiratory tract, creates favorable conditions 

 for the lodgment of organisms and for the general distribution of 

 saliva by coughing, sneezing and spitting. During the war, the 

 highest admission rates in the United States usually fell into the 

 months of November, December and January, which is the time of 

 the highest case rate for most respiratory epidemics. Yet cases will 

 usually trail along through the hot weather. 



Meningitis epidemics, therefore, will occur chiefly in the tem- 

 porate zones during the winter months at times when, during the 

 prevalence of generalized respiratory disease, large numbers of 

 people are crowded in close quarters, under conditions which render 

 attention to hygiene and sanitation difficult. The reasons for this 

 will become apparent as we study the manner of transmission. 



The meningocoecus does not survive easily outside the body, and 



46 Vauglian and Palmer, Jour. Lab. and Clin. Med., 4, 1919, 647. 



