1372 THE ENTEROIDEA GROUP OF TROPICAL FEVERS 



can live, attached to particles of dust, long enough to contaminate 

 food, which in certain tropical regions may become covered with 

 dust. 



Predisposing Causes. — With regard to predisposing causes, it was 

 long considered that the native of the tropics enjoyed a partial or, 

 as some said, an absolute immunity against enteric fever. This 

 cannot be maintained, as we know definitely that enteric fever 

 is quite common in all races. The position at the present time is 

 that, while certain authorities consider that a considerable number 

 of cases of enteric fever still lie hidden under the terms ' remittent 

 fever ' and ' simple continued fever,' and perhaps ' febricula,' as 

 applied to natives, and especially to native children, who are not 

 often treated by physicians trained in modern methods, still, there 

 are others who maintain that there is a partial immunity in some 

 races — e.g., such an immunity is said to exist among the native 

 Egyptians, Sudanese, and Japanese, which is believed to be due to 

 racial inheritance. This question has been investigated by the 

 Board for the Study of Tropical Diseases in the Philippine Islands, 

 and ably reported by Chamberlain, who finds that epidemics of 

 great severity among Filippinos are rare or unnoticed; that Widal 

 reactions performed on the blood of 591 healthy Filippinos suggest 

 a comparatively recent attack of enteric fever in about 6 per cent, 

 of adults, but do not indicate that the disease is prevalent in child- 

 hood; that the native Filippino scouts show a lower typhoid rate 

 than the white troops, possibly due to failure to diagnose the 

 atypical cases; that more than one-third of the cases of enteric 

 fever, whether among Americans or Filippinos, are entirely atypical, 

 and cannot be diagnosed without laboratory methods. One-half 

 of the total number of cases can, however, be diagnosed clinically, 

 and do not differ from enteric fever as seen in the Temperate Zone. 

 He concludes that much work still needs to be done among the 

 natives to estimate the actual aftiount of mild and atypical enteric 

 fever which is occurring, and to determine why extensive and 

 destructive epidemics are not more often seen. 



Our own experience in Ceylon causes us to believe that the disease 

 is very prevalent among the natives of that island, and as 

 dangerous among them as in Europeans. When the causes of 

 death in the races of Ceylon were considered by us some years 

 ago, it was noted that the total deaths contained the following 

 percentages : 



Race. 



Enteric Fever. 



Simple Fever. 



Remittent Fever. 





Per Cent. 



Per Cent. 



Per Cent. 



European . . . . 



lO'I 



1-7 



1-5 



Sinhalese . . 



7-6 



I2'0 



0-3 



Tamils 



0'7 



17-3 



3-8 



