MEDITERRANEAN KALA AZAR 801 



described. 3. Cultures of the parasites are readily obtainable upon Novy and 

 MacNeal's medium in the case of L. infantum, and are easily sub-cultivated, while 

 in the case of L. donovani cultures on this medium are as a rule unsuccessful and 

 sub-cultures cannot be made. On the other hand cultures of L. donovani succeed 

 in citrated splenic blood and usually fail in the case of L. infantum. 4. Inoculation 

 of the spleen parasites into dogs and monkeys reproduces the disease in the case 

 of L. infantum and fails in L. donovani. 5. A spontaneous infection of dogs has 

 been found in the endemic areas of infantile kala azar but no such infection of dogs 

 has been encountered in India."] 



Detection in the tissues. The parasite is invariably found in the material 

 obtained by puncture of the spleen ; the organisms are less numerous in 

 material obtained by puncture of the liver, and in the majority of cases they 

 cannot be found in the peripheral blood 

 (Nicolle). 



Cultures. The organism will not grow in ^* 



Rogers' medium (citrated blood), but cul- ^ * 



tures are easily obtained in Novy-MacNeaPs -^~^ 



or in Nicolle's medium (vide ante). . 



When sown in Nicolle's medium and 



incubated at 22 C. growth begins about the * 0* 



end of the first week and reaches its maxi- 

 mum on the twelfth day. The organism 3jf 1 

 will be found alive at the end of three , 

 months and sub-cultures can be sown in- * 

 definitely (Nicolle). 



Inoculation experiments -Dogs can be 

 infected by inoculating them either into 

 the peritoneal cavity or into the liver with an emulsion of an infected 

 spleen : the distribution of the parasite is the same as in man. The disease 

 usually runs a benign course though several animals have died of the disease 

 after inoculation. 



In monkeys (Macacus sinicus, M. cynomolgus), inoculation gives rise to a 

 disease more severe than in dogs and running a more rapid course. 



When mice and guinea-pigs are inoculated into the peritoneal cavity with 

 an emulsion of tissue from dogs containing a large number of organisms, the 

 latter multiply in the peritoneal cavity but do not become generalized and 

 give rise to no symptoms of disease (Laveran and Pettit). [Nicolle, Yakimoff 

 and Kohl-Yakimoff obtained a generalized infection in white mice by the 

 inoculation of emulsions of infected tissues or of cultures into the vein of the 

 tail. Post mortem the spleen was hypertrophied and parasites were found in 

 the spleen and liver. 



[Dogs can be infected with infected dog tissue by intra-peritoneal inoculation 

 (Senevet).] 



According to Nicolle cultures are not virulent ; Novy however has been 

 able to infect dogs with cultures [and vide supra]. 



Etiology. Nicolle believes that infantile kala azar is of canine origin. 

 [Gabbi, and Patton however do not consider that infantile kala azar is of 

 canine origin. Patton believes that the bed bug Cimex lectularius will be found 

 to act as the insect porter of the disease seeing that L. donovani develops 

 equally in C. lectularius and in C. rotundatus. ] In Tunis, dogs suffer from a 

 natural leishmaniosis but though the spontaneous disease is more benign than 

 the inoculated disease Nicolle believes that the parasite is the same in the two 

 cases. In several cases where children were attacked they had played with 

 dogs which were obviously ill. 



[Naturally infected dogs have been found also in Algiers (Ed. and Et. 



3E 



