920 



THE ANIMAL CARRIERS OF DISEASES 



E. DISEASES OF Ui^KNOWN CADSATION. 



The evidence in favour of pellagra being an insect -borne disease 

 has not increased, and many authorities believe it to be a deficiency 

 disorder. The insects which were accused were species of Simulium 

 and some Chironomid biting flies. There are suggestions that 

 Rocky Mountain fever and tsutsugamushi disease are bacterial 

 infections, and Noguchi has found a spirochaete in yellow fever. 



Disease. 



Host. 



Reservoir. 



Transmission. 



Carrier. 



Infection. 



Pappataci 

 lever. 



Man. 





Blood-sucking. 

 Ingestive. 



Species of 

 phlebotomus. 



Bites. 

 Inoculative. 



Dengue 

 fever. 



Man. 





Blood-sucking. 

 Ingestive. 



Stegomyia 

 culex (?). 



Bites. 

 Inoculative. 



Yellow 

 fever. 



Man. 



Man in 



mild 

 attacks. 



Mon- 

 keys (?). 



Blood--sucking. 

 Ingestive. 



Stegomyia 

 calopus. 



Bites. 

 Inoculative. 



' Rocky 

 Mountain 

 fever. 



Man. 





Blood- sucking. 

 Ingestive. 



Dermacentor 

 venustus — 

 D. andersoTii. 



Bites. 

 I- ) 



Tsutsuga- 

 mushi 

 disease. 



Man. 



A rvicola 

 nataned- 

 zunni (?)/ 



Blood-sucking. 

 Ingestive. 



Micvotrom- 



bidium 

 akamushi . 



Bites. 

 (?) 



Trench fever 

 spiro- 

 chaete (?). 



Man. 





Blood-sucking. 

 Ingestive. 



Lice. 



Bites. 

 Contaminative. 



Typhus. 



Man. 





Blood-sucking. 



Lice. 



Bites. 









Ingestive. 





(?) 



Acute 

 anterior 

 poliomyelitis. 



Man. 





Blood-sucking. 

 Ingestive. 



..... 



Stomoxys 

 calcitrans. 



Bites. 

 Inoculative. 



F. CHANCE TRANSMISSION. 



Numerous blood-sucking and non-blood-sucking insects may by 

 chance obtain an organism and carry it in their proboscis, and 

 directly infect an open sore — e.g., flies and yaws, which, according 

 to Castellani's observations and experiments, is far from a rare 

 occurrence. 



