20 LEISHMANIASIS 



2. Description of species. Kala-azar is caused by Leish- 

 mania donovani; infantile kala-azar resembles kala-azar 

 somewhat and is caused by a related organism, L. infantum; 

 oriental sore is due to the presence of L. tropica; and espundia 

 or American leishmaniasis is caused by L. americana. 



a. L. donovani (Plate II, Fig. F, 1) occurs in many parts 

 of India, Southern China and Northern Africa. It is found 

 only occasionally in the blood, but usually lives within the 

 cells of the spleen, liver, lymph glands and endothelial 

 cells of the blood and lymph vessels. The organisms are 

 spherical or oval in shape and vary from 2 to 4 microns in 

 diameter. Each contains a large nucleus and a small rod- 

 shaped body. Multiplication occurs in the invaded cells, 

 and the parasites, when they break out, are often devoured 

 by leucocytes. When cultivated outside of the body flagel- 

 lated stages appear. The bed bug has been suspected as the 

 transmitting agent. 



b. L . infantum may be only a variety of L. donovani; 

 it exists in certain lands bordering on the Mediterranean, 

 and frequently attacks children. "The organism resembles 

 L. donovani. The transmitting agent is unknown but may 

 be the dog flea. 



c. L. tropica (Plate II, Fig. F, 2) is the causative agent of 

 oriental sore in India, Persia, Syria, Arabia and Northern 

 Africa. The organisms are present outside and within the 

 cells of the sore. They are often spindle shaped and about 

 3 microns long. Flagellate forms have been recovered from 

 bed-bugs 48 hours after feeding on a sore. 



d. L. americana causes espundia in certain regions of 

 tropical South America. Skin sores are produced by the 

 attacking organisms. 



3. Methods of diagnosis. L. donovani and L. infantum 

 should be looked for in leucocytes in the circulating blood 

 or in material obtained from spleen or liver puncture. 



