SANTO INACIO REVISITED - PROTOZOAN DISEASES IN AN ISOLATED VILLAGE INNORTHEASTERN BRAZIL AFTER TWENTY YEARS

The northeastern highlands of Brazil are endemic for several tropical diseases, especially American trypanosomiasis (Chagas' disease) and sc histosomiasis. Twenty years ago, we measured the seroprevalence of pro tozoan diseases in Santo Inacio, a village of approximately 1,000 inha bitants located 1,000 m above sea level. We detected small numbers of sera with antibodies against Trypanosoma cruzi and Toxoplasma gondii, and the area had a low prevalence both of American trypanosomiasis (3. 54%) and toxoplasmosis (27.43%) compared with nearby Brazilian areas. This was attributed to a specific triatomine vector and local housing conditions. Twenty years later, we again determined the prevalences of both diseases and compared these results with those from Iraquara, a larger town with the same ethnic and social background but with a high er prevalence of rural activities. The incidence of Chagas' disease in San Inacio showed the same low level, i.e., 3.78% (5 of 132) with onl y adult males affected in contrast with Iraquara, which had an inciden ce of 34.5%, but a low prevalence of only one of 22 among children up to 14 years of age. Santo Inacio maintained a low (25.8%) seroprevalen ce for toxoplasmosis. Housewives presented a higher incidence of toxop lasmosis during both periods, probably due to related risk factors. Ca ts were found less frequently in Santo Inacio than in Iraquara, which showed an incidence of 65.5% seropositivity for Toxoplasma gondii. The se results suggest that the environmental conditions of Santo Inacio w ere preserved after 20 years, with a low incidence of these selected p rotozoan diseases.