TYPHUS IN GUINEA-PIGS 



OWING to a paratyphoid infection, we lost seventeen of twenty 

 monkeys sent to Warsaw from England, an experience which 

 led us to restrict our animal experimentation to guinea-pigs. 

 Three monkeys were inoculated with blood from two typhus 

 patients. One Rhesus inoculated intraperitoneally with 20 c.c. 

 of blood from patient 116 (sixth day of the disease) failed to 

 react during an observation period of forty-four days. A Cer- 

 copithicus (sabra ?) inoculated intraperitoneally at the same 

 time with 20 c.c. of blood from patient 116 reacted on the 

 thirteenth day and its temperature remained high for six days. 



Three guinea-pigs were inoculated from this monkey on the 

 fifth day of temperature, each with 2 c.c. of blood given intra- 

 peritoneally. One, No. 63, died following a rise of temperature 

 on the fourtheenth day, and the autopsy showed acute peri- 

 tonitis. Two, Nos. 61 and 62, reacted in a manner typical of 

 typhus, both on the fourteenth day. They were killed on the 

 sixth day of temperature and the autopsies showed conditions 

 consistent with typhus. The histological examination of 

 guinea-pig 61 showed the typical lesions of typhus in the 

 cerebrum and cerebellum and in blood vessels of the testes and 

 appendages. 



A third monkey, a Cercopithicus (sabra ?) inoculated intra- 

 peritoneally with 20 c.c. of blood from patient 149 (ninth day 

 of the disease), showed an elevation of temperature from the 

 tenth to the thirteenth days inclusive after inoculation. No 

 controls were made upon this monkey. 



The resistance of Macacus rhesus has been commented upon 

 by Nicolle and Conor (1912). The apparent marked sus- 

 ceptibility of Cercopithicus is of interest as it has not been 

 mentioned among the species tried for susceptibility to typhus. 



The susceptibility of the guinea-pig to typhus was first 

 shown by Nicolle, Comte, and Conseil in 1909, and soon after- 



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