SPIROSCHA UDINNIA NO V YI 



445 



The stage in the liquor sanguinis is associated with the febrile 

 attacks, and that in the cells with the apyrexial intervals. 



Carriers. — It is spread by the agency of Ornithodoros moiihata in 

 Africa, and by Argas americanus (chinche) in Colombia. 



In the Tick. — 5. duttoni in Africa is conveyed to man and animals 

 by faecal infection of the bites of a tick, Ornithodoros mouhata. 

 Leishman has demonstrated that when 5. duttoni enters the intes- 

 tinal sac of the tick it loses its mobility and characteristic appear- 

 ance, and chromatic masses escape into the lumen of the gut in the 

 form of small rods or rounded bodies resembling micrococci. These 

 multiply and pass into the cells of the Malpighian tubules, and also 

 into the immature eggs in the ovary. They can be followed through 

 all the stages of the egg into the adult tick, as small chromatin 

 bodies lying in the cells of the Malpighian tubules. These bodies 

 are voided with the faeces, and when the tick feeds are capable of 

 entering the wound produced by the bite, and in this manner in- 

 fecting the host. 



The tick remains infective for a very long time — according to 

 Moller as long as eighteen months — and the infection can be passed 

 not merely through the eggs into a new generation of ticks, as has 

 been demonstrated by Button, Todd, Leishman, and others, but 

 also according to Moller into the third generation, even if the 

 second generation have only fed on clean animals. 



Pathogenicity. — -It is the cause of West African and Colombian 

 relapsing fever. 



Spiroschaudinnia rossi Nuttall, 1908. 



This spirochcete is distinguished from 5. duttoni by its biological 

 reactions, though some; authorities consider it identical with S. 

 duttoni. It is the cause of East African relapsing fever, and is 

 conveyed by Ornithodoros mouhata. 



Spiroschaudinnia novyi Schellach, 1907. 



History. — In 1907 Professor Manteufel, while investigating an 

 accidental laboratory infection of relapsing fever, found that the 

 serum of the patient agglutinated a spirochaete found by Novy in 

 a case of relapsing fever in America in a dilution of i in ico, but 

 showed no such power over the spirochaete of the European disease. 

 Moreover, it gave Pfeiffer's reaction, being active in doses of 0-05 c.c. 

 in experimentally^ infected mice. Schellach has investigated this 

 spirochaete, and given it the specific name used above. 



Morphology. — ^It is 17 to 20 in length, with six to eight undula- 

 tions and a thickness of 0-31 He gives the dimensions for the 

 S. recurrentis as 19 to 29 ^, with eight to ten undulations and a 

 thickness of 0-39 [jl, and S. duttoni as 24 fc at the most, with eight 

 to ten undulations and a thickness of 0-45 /^i which appear to be 

 very different from Novy's table given under 5. carteri. 



The spirochaete appears to have great flexibility and activity 

 of movement. One end has a filiform prolongation about 5 ju in 



