INFECTIVE JAUNDICE 601 



infected, and the infection may be transmitted to the 

 third generation of ticks. 



Duval and Todd l state that multiplication of S. Dutloni 

 takes place in vitro in a culture medium made with hens' 

 eggs and mouse blood. Leishman believes that certain 

 chromatin bodies present in the eggs and nymphs of the 

 ticks are the developmental forms of the spirochaete. 



Spirochaeta (Leptospira) icterohcemorrhagice. This is the 

 cause of Weil's Disease, Febrile or Infective Jaundice 

 (Spirochaetosis icterohsemorrhagica) . 



This disease occurs in epidemic and endemic form in 

 Japan and other localities, and is met with occasionally 

 in Europe during the war in Germany and on the 

 Western front. In 1914 Inada 2 and co-workers dis- 

 covered a spirochaete in the blood of a patient, and this 

 has been confirmed by other observers. The organism is 

 present in the blood only in the early stage of the disease, 

 and then only in small numbers. It is most abundant 

 in the liver (Plate XXV, a), sections of which may be 

 stained by the Levaditi method (p. 613), and may be met 

 with in the spleen, adrenals, kidneys and urine. It 

 averages 6-9 ju, in length, but shorter (4-5 //,) and longer 

 (12-20 p) forms occur. Guinea-pigs may be infected by 

 intraperitoneal inoculation with blood taken in the first 

 three to six days of illness, and succumb in from five to 

 eight days. The spirochaete may be cultivated by 

 inoculating melted blood-agar or gelatin with blood, 

 covering with a layer of paraffin and incubating at 

 20-25 C. for ten to fourteen days. The organism is a 

 natural inhabitant of the various species of rats and the 

 field- vole. It may be transmitted directly from animal to 

 animal, or possibly by fleas, etc., or by water, food, or 



1 Lancet, 1909, vol. i, p. 834. 



2 Journ. Exper. Med., vol. xxiii, 1916, pp. 377 and 557 : Foulerton, Journ. 

 Pathol. and Bacterial., vol. xxiii, 1919, p. 87. 



