PREVENTIVE MEDICINE AND THE WAR 339 



ing the summer, but neither became epidemic. The annual 

 death rate for typhoid fever during this season was 3.3 per 

 100,000. When we compare this with the death rate of 897 

 per 100,000 in the summer of 1898 we can have some appre- 

 ciation of the great advance in the prevention of this disease 

 which for many centuries has been the captain of the cohorts 

 of death in the armies of the world. Even this showing would 

 have been surpassed had not some men reached the camps in 

 an infected state. Typhoid fever was prevented by the 

 chlorination of the water supplies and by specific vaccination. 

 Incidentally the first of these proceedings prevented dysentery, 

 diarrhea and similar gastro-intestinal ailments. Although 

 some of the camps were located in malarial districts, so effi- 

 cient was the destruction of mosquitoes that there is no evi- 

 dence that any soldier was infected by these pests in any camp. 

 There were a few cases but all such brought the infection with 

 them and proper treatment made short-shift of these, undesired 

 guests. 



THE AUTUMN OF 1918 



Early in September came the great pandemic of influenza 

 with pneumonia. This is the most deadly pestilence which 

 has ever visited us and it ranks high among the epidemics of 

 history as is shown in Table 4. 



Preventive medicine is making rapid progress. Malaria 

 and typhoid fever, once the scourges of armies, are well in 

 hand. Typhus is no longer an enigma but still requires close 

 watching. The pneumonias remain and constitute at present 

 the greatest cause of death in all armies. Protective inocula- 

 tion against the pneumonias has been tried only recently, and 

 the results are promising. The combination of influenza and 

 pneumonia has been most distressing and disastrous both in 

 military and in civilian populations. During the Autumn Sea- 

 son of 1918, civilian communities suffered greatly but on ac- 

 count of the high concentration of susceptible material in our 

 camps, the death rate among soldiers has been higher than 



