BARTONELLA BACILLIFORMIS 179 



tion was favorable to recovery, a belief undoubtedly based upon 

 the benign nature of verruga, leads to the adoption of all sorts of 

 methods to invoke a breaking out of the skin, such as applications 

 of turpentine, rubbing with irritant leaves, etc., and undoubtedly 

 a great many cases of eruptions following Oroya fever are really 

 only the eruptions caused by the artificial irritation of the skin. 



Oroya fever, after an incubation period of about 20 days, begins 

 with a general feeling of malaise and aches in the joints, followed 

 by chills and fever, which last irregularly for many weeks. The 

 fever is accompanied by a rapid pernicious anemia, the red blood 

 corpuscles being reduced in some cases to one-fifth, or even less, 

 of their normal number. This causes severe prostration and 

 in a large per cent of cases death results within three or four 

 weeks. The skin assumes a yellowish waxy color, and there are 

 often slight hemorrhages of the mucous membranes and various 

 internal organs, as demonstrated by post mortem examinations. 

 The liver and spleen become moderately enlarged, and the lymph 

 glands are swollen. 



The Parasite. — The true parasite of Oroya fever was first 

 discovered by Barton, of Lima, Peru, in 1905 and confirmed by 

 him in 1909, at which time he 

 suspected that it might be a 

 protozoan. The parasites were 

 more thoroughly studied by 

 the Harvard expecUtion in 1913 

 and 1914 and named Barton- 

 ella bacilli formis. Dr. Strong 

 and his colleagues describe 



them as minute rods or, more Fig. 54. Bartonella badUiformis, liv- 



1 ] ^ U ^" ^^"' -^' ^ ^"*^ ^' successive drawings of 



rarely, rouncled. DOaieS occur- ^^ gji^gie j-pj corpuscle showing movements 



ring inside the red blood cor- of parasite within it; D.E" and F, corpuscle 



1 /XT'" ~A ^ p;^^ containing two rod-shaped and four round 



pUSCleS (rigs. o4 and OOJ. parasites, showing migrations of the rod- 



These parasites, the rod form shaped indi\nduals. X 2000. (After 



1 1 c 4- o - Strong et al.) 



of which are only 1.5 to 2.o m 



(less than y^tWs^ o^ ^" inch) in length and the round bodies 0.5 to 

 1 /i in diameter, are definitely motile, moving about freely inside 

 the corpuscles. In severe infections there may be found from 

 one to ten parasites in a single corpuscle. 



A multiplicative stage of the parasite occurs in large swollen 

 endothelial cells in the lymph glands and spleen. In these swollen 



