48 
TYPHOID FEVER IN DISTRICT OF COLUMBIA. 
MOSQUITOES. 
Twenty-six cases occurred among persons living in houses where 
there were no mosquitoes, 263 in houses where there were few, 381 
in houses where there were mosquitoes in moderate number, 65 in 
houses where there were many, and 12 in houses where the number 
was not noted. 
ANTS. 
Three hundred and nine cases occurred among persons living in 
houses where there were no ants, 155 in houses where there were few, 
249 in houses where there was a moderate number, 20 in houses where 
there were many, and 14 in houses where the number was not noted. 
ROACHES. 
Two hundred and two cases occurred among persons living in 
houses where there were no roaches, 151 in houses where tDere were 
few, 332 in houses where there was a moderate number, 29 in houses 
where there were many, and 33 in bouses where the number was not 
determined. 
BEDBUGS. 
Two hundred and sixty-one cases occurred among persons living 
in houses where there were no bedbugs, 100 in houses where there 
were few, 324 in houses where there was a moderate number, 13 in 
houses where there were many, and 49 in houses where the number 
was not determined. 
RATS ON PREMISES. , ' 
Three hundred and seventy-five cases occurred among persons 
living in houses where there were no rats, 49 at houses where there 
were few, 301 at houses where they were in moderate numbers, 11 at 
homes where there were many, and 11 at homes where the number 
was not determined. 
MICE. 
Three hundred and thirty-seven cases occurred among persons 
living in houses where there were none, 121 in houses where there were 
few, 270 in houses where they were in moderate numbers, 5 in houses 
where there were many, and 14 in houses where the number was not 
determined. 
In obtaining these data in regard to insects, rats, and mice, etc., as 
much as possible was learned by inspection, and for the remainder 
the statements of persons living at the residence were accepted. 
Most of the cases investigated occurred in a period when the average 
temperature was high and the rainfall great — conditions probably 
.favorable to most insect life and also tending to cause large numbers 
to remain in houses. 
