572 Kala-Azar 



One successful infection with the parasite usually confers immunity; 

 unsuccessful intraperitoneal introduction of large quantities of 

 culture produce no immunity. 



Transmission. — The disease can be transmitted by inoculation 

 from human being to human being. 



The usual mode of transmission is not known, but as the lesions 

 usually occur where the body surface is uncovered, it may be that 

 flies or other insects act as vectors of the parasites. 



Preventive Inoculation. — Jackson* is authority for the statement 

 that " the Jews of Bagdad recognized that tropical ulcer is inoculable 

 and autoprotective years ago, and practised vaccination of their 

 children upon some portion of the body covered by clothing, in 

 order that their faces and other exposed parts of the body be not 

 disfigured by the ulcers and the resultant scars." NicoUef sought 

 to vaccinate according to modern njethods with killed and liv- 

 ing cultures of the organism, and was successful when he first 

 used a killed culture, then after a year a live culture, and then three 

 months later another live culture. 



Treatment. — Row t has endeavored to cure already existing 

 lesions by vaccination, and has met with what seems to be encour- 

 aging success. Cultures of the organism were permitted to grow for 

 seven days, then sterilized with glycerin. Patients can bear 0.25 

 cc. at a dose, there is little febrile reaction, and the lesions proceed 

 to heal nicely. 



HISTOPLASMOSIS 



HiSTOPLASMA CaPSULATUM (DARLING) 



In 1906 Darling, § working at the Isthmus of Panama, observed 

 certain cases presenting pyrexia, anemia, leukopenia, splenomegaly, 

 and emaciation, and bearing a close resemblance to kala-azar. The 

 disease was quite chronic, and it terminated fatally. When ex- 

 amined at autopsy, these cases showed necrosis with cirrhosis of 

 the liver, splenomegaly, pseudo-granulomata of the lungs, small 

 and large intestines, ulceration of the intestines, and necrosis of 

 the lymph nodes draining the infected viscera. The lesions seemed 

 to depend upon the invasion of the endothelial cells of the smaller 

 lymph- and blood-vessels by enormous numbers of a small encap- 

 sulated micro-organism. 



The organism is small, round or oyal in shape, and measures i 

 to 4 ;u in diameter. It possesses a polymorphous, chromatin nucleus, 

 basophilic cytoplasm, and achromatic spaces all enclosed within an 

 achromatic refractile capsule. 



* "Tropical Medicine," Phila., P. Blakiston's Son & Co., igo;, p. 478. 

 t "Annales de ITnst. Pasteur," Tunis, 1908. 

 t "Brit. Med. Jour.," 1912, i, 540. 



§ "Jour. Amer. Med. Assoc," 1906, xlvi, 1283; "Archiv. of Int. Med.," 1908, 

 n, 107; "Jour. Exp. Med.," 1909, xi, 515. 



