66 



THE HEMOFLACELLATES 



Hoare (1949), Kirk (1949, 1950) and Biaga 

 (1953) among others. While some 22 dif- 

 ferent specific or subspecific names have 

 been given to mammalian leishmanias, and 

 while different strains are associated with 

 different types of disease, neither morpho- 

 logic, cultural nor immunologic characters 

 can be used to differentiate the species of 

 Leishiiia)iia. In practice, the species are 

 separated on the basis of pathologic and 

 epidemiologic differences and, since most 

 studies have been made by parasitologists 

 oriented toward human disease, the patho- 

 logic characters used for each strain have 

 been those seen in man. In the earlier 

 days of our knowledge, when relatively few 

 types were known, it was quite easy to de- 

 lineate their characteristics and set up 

 separate species, but as more studies 

 were made, intermediate types were found 

 and the boundaries between species tended 

 to disappear. 



Some parasitologists consider that all 

 the leishmanias of man and dogs should be 

 assigned to a single species. Others pre- 

 fer to assign them to two species, and 

 still others to three. One can justify each 

 of these schemes, but in all of them each 

 species is still composed of a number of 

 strains or demes. 



In this book, two species of Leish- 

 mania are recognized: L. doiiovani, 

 causing various visceral forms of disease, 

 and L. tropica, causing various cutaneous 

 and mucocutaneous forms. The third spe- 

 cies recognized by some authorities is 

 L. hrasiliensis, which causes a mucocu- 

 taneous form of the disease. 



Maps of the world distribution of 

 leishmanioses together with climatologic 

 and other information have been published 

 by Piekarski (1952), Piekarski and Sibbing 

 (1954), Piekarski, Hennig and Sibbing 

 (1956, 1958a), the American Geographical 

 Society (1954) and May (1954). 



LEISHMANIA DONOVANI 

 (LAVERAN AND MESNIL, 1903) 

 ROSS, 1903 



Synonyms : Piroplasma donovani, 

 Leishmania infantum, L. canis, L. chagasi. 



Disease : Kala-azar; dum-dum fever; 

 visceral leishmaniosis. 



Hosts : Man and the dog are the prin- 

 cipal hosts of L. donovani. Infections have 

 also been reported in the cat by Sergent 

 el at. (1912) and Bosselut (1948), in the 

 sheep by De Paolis (1935) and in the horse 

 by Richardson (1926). 



Location : L. donovani occurs in the 

 cells of the reticulo -endothelial system, 

 including both the endothelial cells and the 

 circulating monocytes and polymorphonu- 

 clear leucocytes. The parasites are found 

 thruout the body, but particularly in the 

 endothelial cells of the blood and lymph 

 vessels of the spleen, liver, bone marrow, 

 lungs, kidneys, mesenteric lymph nodes 

 and skin. 



Types of Disease, Geographic Distri - 

 bution and Epidemiology : 



Five types of visceral leishmaniosis can 

 be recognized: 



1. Indian kala-azar or dum-dum fever is 

 the classical type of the disease. It is 

 found in India and affects young adults 

 (60%) and children 5 to 15 years old. 



It does not occur naturally in dogs altho 

 they can be infected experimentally. It 

 is transmitted by Phlebotoums argen- 

 tipes. 



2. Sudanese kala-azar is found in the 

 Sudan and Abyssinia. It affects people 

 of the same ages as Indian kala-azar 

 and does not occur naturally in dogs. 

 It was found once in a horse (Kirk, 

 1956). Oral lesions are frequently 

 present, and this type of the disease is 

 relatively refractory to treatment with 

 antimony compounds. It is transmitted 

 by P. orientalis. A similar form oc- 

 curs in small, isolated pockets scat- 

 tered thru Africa south of the Sahara. 

 It may cause skin lesions in addition 



to the visceral ones. It is a zoonosis, 

 and has been found in a gerbil ( Tatera 

 vicina) and a ground squirrel {Xenis 

 )7<////fs)(Manson-Bahr, 1959). 



3. Chinese kala-azar is found in northern 

 China. It is more common in children 



