[Kala-azar in Portugal. III. Results of a survey on canine leishmaniasis performed in the Lisbon region. Comparison of urban and rural zones].

A serological and parasitological survey of dogs was done in four slum areas on the outskirts of Lisbon and a rural area west of Setúbal. The serological test was the IFAT. The total number of dogs examined was 572 which 55 (9,6%) had titre greater than or equal to 1/128, 10 of these dogs were among 182 (5,5%) in the urban areas and 45 were in the sample of 390 dogs (11,5%) in the rural area. 23 dogs with titres of greater than or equal to 1/128 were examined parasitologically. The methods were the examination of tissue from popliteal lymph nodes (by direct examination and the inoculation of NNN cultures and hamsters), the direct examination of stained smears from sores and the direct examination of stained smears of healthy skin. Parasites were demonstrated in 15 (65,2%) of the 23 dogs. 14 dogs with high titres were followed up by a second IFAT. 5 had become higher, 5 had remained the same and, in 4, the titres had fallen. The results of the survey suggest that canine leishmaniasis is more common in the rural area than in the urban sites. The disease in man in the focus studied appears to be accidental and, paradoxically likely to be acquired rather in the town than in the villages. The reason is probably related to zoophilic preference of vector, and the fact that the population in rural areas is widely dispersed.