CARRIAGE OF DISEASE 151 



without communicating with the shore, the flies re- 

 turned in greater force, and the cholera also with in- 

 creased violence. After more cruising at sea, the flies 

 disappeared gradually with the subsidence of the dis- 

 ease." 



C. Flugge is said by Nuttall and Jepson to have ex- 

 pressed his belief in 1886 that flies may infect the food 

 in cholera times. Their numbers vary extraordinarily 

 at times and in certain places. They must play an im- 

 portant part, especially when they are numerous. He 

 drew attention to the fact that the worst cholera months 

 are those in which insects abound. 



Dr. J. Tsuzuki, of the Japanese Army Medical Ser- 

 vice, writing in 1904 upon his researches during the 

 cholera epidemic in North China in 1902, stated that 

 flies in China are a terrible infliction to the stranger, 

 and that if they are capable of carrying the cholera 

 germ they must play an important part in the spread 

 of the disease. He captured flies in Tientsin in houses 

 in which there were cholera patients, and succeeded in 

 isolating cholera vibrios from them. He also placed 

 flies in a cage with a cholera culture and a dish con- 

 taining sterilized agar, with the result that cholera col- 

 onies developed upon the agar. 



But this was not the first definite and conclusive ex- 

 periment in this regard, since Nuttall and Jepson point 

 out that something had been done in 1886 by two 

 Italian physicians in Bologna, and that Sawtchenko, of 

 St. Petersburg, in 1892, found that when flies had fed 

 for some time on a cholera culture almost no other 



