KALA-AZAE COMMISSION 167 



Infection of dogs was, therefore, not obtained, but it is difficult to account for the 

 mortality. Probably the mortality in Dogs F and G, which were re-inoculated on the 

 16th day with the contents of a splenic puncture (Leishman-Donovan parasites not being 

 seen in smears made from the original liver puncture with which they were inoculated), 

 may be attributed to some anaphylactic effect of the body fluids from Monkey E. Dog D 

 became emaciated, developed an abscess in the axilla, and we thought it would bo infected, 

 particularly as the spleen was found enlarged after death. Unfortunately, the post mortem 

 examination was not done until some hours after death, when the spleen pulp was too 

 soft for satisfactory examination, but the bone-marrow contained no parasites. As Dog D 

 was the only one which lived long enough to become infected with the disease, further 

 experiments are necessary to determine if the dog can be experimentally infected with 

 the Sudan form of kala-azar. 



A large amount of experimental work has now been done on kala-azar in the dog. Kala-azar m 

 NicoUe and his colleagues have frequently infected dogs. They find in dogs that the 

 infection is an insidious one with only slight enlargement of the spleen. One of the 

 dogs which they inoculated with the disease and which died 17 months after inoculation 

 showed no symptoms for 15 months. They also found that in a series of dogs there was 

 great variation in the susceptibility of the individual animal. They found no attenuation in 

 the virus by passage from dog to dog. With regard to immunity they have found that in an 

 animal incompletely cured or only just recently recovered, a second inoculation produces a 

 severe and fatal result, whereas, in an animal cured for some time immunity is conferred. 

 Excision of the spleen in the dog has produced no effect on the course of the disease. 



Jemma, Gabbi, and Alvarez and Pereira da Silva, have also all succeeded in infecting 

 dogs intraperitoneally with LeishiiMuia infantum. Basile was able to infect three young 

 dogs by keeping them beside cases of infantile kala-azar and he thinks the flea {Fulcx 

 serraticeps and perhaps Pulex irritans) is the likely transmitting agent. Jenuna has also 

 been able to infect dogs intravenously as well as intraperitoneally. 



Novy, by the use of large and repeated doses of cultures of Leislimania infantuin on 

 Novy and MacNeal's medium, has been able to produce infection in the dog. 



Patton, working with Indian kala-azar, failed to infect dogs even with repeated 

 inoculation, but probably he killed his animals too soon to say definitely that infection 

 does not occur. 



MOKI'HOLOGY AND CuLTUKE OF THE PaEASITE 



The parasites in these cases do not appear to difl'er in structure from the parasites , 

 described in Indian kala-azar and in infantile kala-azar. The parasites were sometimes 

 present in spleen cells and sometimes lying free. So-called developmental forms were 

 frequently found containing up to as many as 11 nuclei. Our observations agree with those 

 of other observers who find that, when a large amount of blood is obtained in spleen 

 puncture, the parasites are scanty and difficult to find. There is definite evidence that the Rapid 

 parasite degenerates quickly after death. As shown above, in one case where the parasites of the parasites 

 were found m large numbers during life the x^ost mortem examination, 8 hours after death, after death 

 showed no parasites in the spleen. In another case, examined 4 hours after death, the 

 parasites were present but showed evidences of degeneration, the nucleus and kinetonucleus 

 being visible, but no protoplasm. 



In two cases the parasites were successfully cultivated in 10 per cent, citrate. 

 Flagellated forms were found as early as the second day, but seemed to be most numerous 

 and most active on the 4th and 5th days. The parasites move very slowly with the 



