A CROSS-SECTIONAL SERODIAGNOSTIC SURVEY OF CANINE LEISHMANIASIS DUE TO LEISHMANIA-CHAGASI

Jequie, a community of about 144,500 inhabitants located in the State of Bahia, Brazil, is endemic for both visceral and cutaneous leishmani ases. In the present epidemiologic study, the urban and inhabited peri urban areas of the town were divided into 140 clusters of 0.25 km(2) e ach. The seroprevalence of canine Leishmania antibodies was investigat ed using an enzyme-linked immunosorbent assay as a screening test sinc e its sensitivity was significantly higher than that of an indirect im munofluorescence assay, A total of 1,681 dogs was surveyed in 34 rando mly sampled clusters. The overall prevalence of Leishmania antibodies in the dog population was 23.5%, with intracluster prevalences ranging from 0% to 67%. There was no correlation of these seroprevalences wit h the intracluster densities of canine populations, or with the distan ces from individual clusters to the town center. Moreover, the Leishma nia transmission did not seem to follow any clear-cut spatial pattern, since large disparities in the seroprevalences of contiguous clusters were found. Curiously, human cases of visceral leishmaniasis have nev er been observed in some clusters with a relatively high prevalence of canine seroprevalences. Eight parasite isolates from seropositive dog s were found to belong to the same serodeme and zymodeme as Leishmania (L.) chagasi. The implications of these findings with respect to the epidemiology and control of American visceral leishmaniasis are discus sed.