PROTOZOA IN THE CIRCULATORY SYSTEM 81 



When citrated l)lo()d or culture tube with blood-agar 

 (p. 10) is inoculated with Leishmania and incubated at 

 20-24°C., the leishmania l:)odies become elongate and 

 the rhizoplast develops into a flagellum in about 48 hours 

 (Fig. 20, 4-6). Thus Leishmania develops into leptomonad 

 flagellate. 



The transmission is most probably carried on by Phle- 

 hotomus spp., sandflies, in the digestive tube of which 

 flagellates identical with the cultural forms, develop after 

 ingestion of the blood of a suspected subject. 



To detect Leishmania donovani, smears of peripheral 

 blood should be made and examined (p. 97). The number 

 of the organisms in the blood is ordinarily very small, but 

 it is the simplest method and should be the first step to 

 be taken. Look for the parasites in large mononuclear 

 leucocvtes. The best result is of course obtained by exam- 

 ining stained smears of spleen puncture. The organisms are 

 far more numerous there than in the blood smear and the 

 detection is easily done. 



2. Leishmania tropica (Wright 1903) 



This is the causal organism of the Oriental sore or cu- 

 taneous leishmaniasis. It has been reported from Africa 

 (mainly regions bordering the Mediterranean Sea), Europe 

 (Spain, Italy, France, and Greece), Asia (Syria, Palestine, 

 Armenia, southern Russia, Iraq, Iran, Arabia, Turkestan, 

 India, Indo-China, and China), and Australia (northern 

 Queensland). The organism occurs in the endothelial cells 

 in and around the cutaneous lesions, located on hands, 

 feet, legs, face, etc. 



Leishmania tropica is morphologically indistinguishable 



