PROTOMONADINA 355 



Genus Leishmania Ross. In man or dog, the organism is an ovoid 

 body with a nucleus and a blepharoplast; 2-5;u in diameter; with 

 vacuoles and sometimes a rhizoplast near the blepharoplast; intra- 

 cellular parasite in the cells of reticuloendothelial system; multi- 

 plication by binary fission. In the intestine of blood-sucking insects 

 or in blood-agar cultures, the organism develops into leptomonad 

 form (Fig. 148, d-j) which multiplies by longitudinal fission. Nuclear 

 division (Roskin and Romanowa, 1928). 



There are known at present three "species" of Leishmania which 

 are morphologically alike. They do not show any distinct differential 

 characteristics either by animal inoculation experiments or by cul- 

 ture method or agglutination test. 



Species of Phlebotomus (sand-flies) have long been suspected as 

 vectors of Leishmania. When a Phlebotomus feeds on kala-azar 

 patient, the leishmania bodies become flagellated and undergo 

 multiplication so that by the third day after the feeding, there 

 are large numbers of Leptomonas flagellates in the mid-gut. These 

 flagellates migrate forward to the pharynx and mouth cavity on the 

 4th or 5th day. On the 7th to 9th days (after the fly is fed a second 

 time), the organisms may be found in the proboscis. But the great 

 majority of the attempts to infect animals and man by the bite of 

 infected Phlebotomus have failed, although in a number of cases 

 small numbers of positive infection have been reported. Adler and 

 Ber (1941) have finally succeeded in producing cutaneous leish- 

 maniasis in 5 out of 9 human volunteers on the site of bites by lab- 

 oratory-bred P. papatasii which were fed on the flagellates of 

 Leishmania tropica suspended in 3 parts 2.7% saline and 1 part de- 

 fib rinated blood and kept at a temperature of 30°C. Swaminath, 

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

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



L. donovani (Laveran and Mesnil) (L. infantum, Nicolle) (Fig. 148). 

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

 (1-3/x) or ovoid (2— 4/x by 1.5-2.5/z); 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, 

 Abyssinia, Sudan, northern Kenya and Nigeria), in Asia (India, 



