DISSEMINATION OF INFECTIOUS DISEASES BY INSECTS. 
267 
consider the life-histories of the house-fly and the mosquito, that 
filth is a natural and seemingly necessary condition for their 
reproduction, can we doubt that when they arise from their 
filthy breeding places they carry with them large numbers of 
bacteria, some of which may be capable of producing disease ? 
Can we doubt that in the sick-room of the ignorant and care¬ 
less, where flies are allowed to alight upon tuberculous sputum, 
the dejections of cholera and typhoid patients, that they may 
and do transport these deadly enemies of mankind ? When we 
consider the many favorable conditions for the spread of disease 
by this means, even in carefully-kept houses, the wonder is that 
we escape the constant dangers. 
The literature on this subject shows that there are numerous 
reported cases, some of which are supported by experimental 
data, where all evidence points to the fact that the disease had 
been transmitted by insects. 
In the Medical Record of Sept. 17, 1892, is the fol¬ 
lowing : 
u Bed-bugs, according to Dr. Dewevre, may be carriers of 
tuberculous contagion. His attention was called to this possi¬ 
bility by a case of tuberculosis occurring in a young man who 
slept in a bed formerly occupied by his brother, who died of the 
disease. The room had been thoroughly disinfected, but the 
bedstead for some reason had escaped this sanitary process. Dr. 
Dewevre observed that the young man had been bitten by the 
insects, and securing some of these, found them to be full of 
tubercle bacilli. He afterwards put some presumably healthy 
bugs in contact with tuberculous sputum, and was able to ob¬ 
tain from these, several weeks later, some excellent cultures of 
tubercle bacilli.” 
Sir William Moore (Brit. Med. Journal ', Vol. I, p. 1154, 
i 893), while in the Indian service, writes as follows : 
“ When mentioning the necessity of protecting food from 
flies coming fresh from the evacuations of a cholera-stricken 
patient and so conveying the cholera poison to articles of food 
they might investigate. My impression, long held, that flies 
