PROTOMONADINA 283 



Shortt and Anderson (1942) also succeeded in producing kala-azar 

 infections in 3 out of 5 volunteers through the bites of P. argentipes. 



L. donovani (Laveran and Mesnil) (L. m/an^wm Nicolle) (Fig. 127). 

 As seen in stained spleen puncture smears, the organism is rounded 

 (l-3ju) or ovoid (2-4/x by 1.5-2.5^); cytoplasm homogeneous, but 

 often with minute vacuoles; nucleus comparatively large, often 

 spread out and of varied shapes; blepharoplast stains more deeply 

 and small; number of parasites in a host cell varies from a few to 

 over 100. 



This is the cause of kala-azar or visceral leishmaniasis which is 

 widely distributed in Europe (Portugal, Spain, Italy, Malta, Greece, 

 and southern Russia), in Africa (Morocco, Algeria, Tunisia, Libya, 



Fig. 127. Leishmania donovani, XlloO (Kudo). 1, an infected poly- 

 morphonuclear leucocyte; 2, leishmania bodies scattered in the blood 

 plasma; 3, a large endothelial cell infected by the organisms; 4-6, flagel- 

 late forms which developed in the first five days of cultivation in blood- 

 agar medium. 



Abyssinia, Sudan, northern Kenya and Nigeria) and in Af^ia (India, 

 China, Turkestan, etc.). The parasite is most abundantly found in 

 the macrophages, mononuclear leucocytes, and polymorphonuclears 

 of the reticulo-endothelial system of various organs such as spleen, 

 liver, bone marrow, intestinal mucosa, lymphatic glands, etc. 

 The most characteristic histological change appears to be an in- 

 crease in number of large macrophages and mononuclears. The 

 spleen and liver become enlarged due in part to increased fibrous 

 tissue and macrophages. 



The organism is easily cultivated in blood-agar media (p. 716). 

 After two days, it becomes larger and elongate until it measures 

 14-20)Li by 2/x. A flagellum as long as body develops from the bleph- 

 aroplast and it thus assumes leptomonad form which repeats 



