32« ANNÉE FÉVRIER 1918 N" 2 



ANNALES 



DE 



L'INSTITUT PASTEUR 



Mémoire publié à l'occasion du jubilé de E. Metchnikoff. 



A NOTE ON THE " GRANULE-CLUIVIPS " FOUND 



IN ORNITHODORUS mOUBATA 



AND THEIR RELATION TO THE SPIROCHAETES 



OF AFRICAN RELAPSING FEVER TICK FEVER) 



by Colonel Sir WILLIAM B. LEISHMAN 



C.B., M.B., F.R.C.P., F.R.S., LL.D., K.H.P., A. M. S. 



in 1908 1 obtained a number of Oniithodorus moiibata from 

 Nyasaland and from Uganda, with a view to stutlying tlie 

 course of events in Tick Fever in expérimental animais. After 

 several failures I eventually secured a batch of ticks which 

 proveci to be infective and by their bites produced in a monkey 

 a typical attack of Relapsing Fever, associated witli the occur- 

 rence of large numbers of SpirochaeLa duttoni in the blood. 

 I was then able to infect a number of ticks by allowing them 

 to gorge themselves on this infected monkey and hâve, since 

 then, been able to maintain the strain of spirochaetes, either by 

 passage from mouse to mouse or through the bites of infected 

 ticks. I was thus in a position to study the fate of spirochaetes 

 ingested by the ticks, as well as such questions as the nature 

 of the hereditary transmission of the infection in the tick, the 

 mechanism of infection by the bite of the tick, and other points. 



