1908] 



on the Extinction oj Malta Fever. 



25 



Epidemiological Features. 



Here, then, at last was discovered a mode of infection which 

 explains the curious features of Malta fever — the irregular seasonal 

 prevalence, the number of cases which occur during the winter 

 months, when there are no mosqnitoes and little dust. It is true 

 there are more cases in summer than in winter, but this may be ex- 

 plained bj the fact that more milk is used at that time of the year 

 for fruit, in ice-creams, etc. It also explains the fact that officers 

 are more liable than the men, as the former consume more milk than 

 the latter. It also explains the liability of hospital patients, milk 

 entering so largely into a hospital dietary. 



Fig. 7.— Chart of Incidence in 1899-1905, and 1905. 



Result of Measures Directed Against 

 THE Use of Goat's Milk. 



As soon as goat's milk was discovered to be the source of infec- 

 tion, preventive measures were begun. The result is very striking, as 

 is shown in the charts thrown on the screen, which give the number 



