[Canine visceral leishmaniasis: evaluation of the serologic method used in epidemiologic studies]

A comparative study was made of eluates of the blood of dogs experimentally infected with different trypanosomatids. Using antigens prepared from promastigotes of Leishmania mexicana, L. braziliensis and L. chagasi, assessments were made by the indirect immunofluorescence test. The results showed a sensitivity of 87.5% in the diagnosis of canine visceral leishmaniasis, independent of antigen used. Cross-reactions occurred in 75% of cases of cutaneous leishmaniasis and 83.3% of dogs with chagas' disease. An epidemiological survey in an area of leishmaniasis confirmed that immunofluorescence tests on eluates of dogs' blood give cross-reactions between L. braziliensis and L. chagasi. The results suggest that such testing could be useful in public health campaigns but attention is drawn to the fact that the level of positive reactions cannot be used as an indicator of the prevalence of canine kala-azar.