210 APPLIED BACTERIOLOGY 



RELAPSING FEVER. 



Obermeier's spirillum is the specific cause of the disease — Morphology — 

 Methods of staining — Attempts at culture hitherto unsuccessful — 

 Experiments on monkeys — Pathogenesis — The disease is not common 

 at the present day — Practical disinfection. 



In the year 1873 Obermeier described the spirillum that 

 bears his name, which he found in the blood of patients 

 suffering from relapsing fever during the febrile period. 

 The organism is motile, and some observers believe it to 

 form spores. The spirillum is very much longer and 

 thinner than most other organisms, being about 8 /x 

 long and about O'l fi thick. The organisms are pointed at 

 the ends, and are peculiar in having no sheath, so that 

 if treated with caustic potash they entirely dissolve. 



Method of Staining. — It is stated that the organism can 

 be stained by all the ordinary basic aniline dyes, but both 

 Schenk and Wlirtz recommend Giinther's method, who 

 places the air-dried cover-slips in 5 per cent, acetic acid for 

 ten seconds to bleach the blood corpuscles. The acid is 

 then removed by blowing, and the last traces neutralised 

 by exposure to the vapour of strong ammonia. The cover- 

 slips are then stained by an aniline-water solution of 

 gentian violet, rinsed in water, and put up in Canada 

 balsam. 



Growth on Media. — No attempt at artificial culture has as 

 yet been successful, though it has been found possible to 

 keep the organisms alive for some time in a saline solution. 

 It has also been found possible to communicate the disease 

 to monkeys by inoculating them with the blood of relapsing 

 fever patients, and it has further been shown that the 

 spleen plays an important part in the recovery of these 



