Preliminary inquiry about Trypanosoma cruzi infection in domestic dogs and cats in Campo Florido, Minas Gerais, Brazil

Abstract

In order to estimate the epidemiologic importance of dogs and cats as domestic sources of infection by Trypanosoma cruzi for Trialomidae at the endemic community of Campo Florido, in the Triângulo Mineiro region in the State of Minas Gerais, Brazil, the A.A. conducted a preliminary inquiry there and obtained the following results: 1) The application of xenodiagnosis on 47 cats revealed 12 of them to be infected (25.5%); the same method showed that 8 dogs were infected, out of a total of 102 (7.8%); 2) The reaction of complement fixation, applied to the sera of 151 dogs, was conclusive in 143 of them and of these, 16 (11.2%) were positive; 3) In 57 dogs, submitted both to xenodiagnosis and complement fixation reaction, the first test revealed 3 positives (5.26%) while the second showed the infection in 6 (10.53%); as in our previous experience in man (Freitas, 1950) the xenodiagnosis revealed only about 10% of the cases uncovered by complement fixation reactions, it seems that infected dogs are really more infective to Triatomiduc than infected men; 4) Infection by T. cruzi was observed in 61 of 272 specimens of T. infestans examined (22.4%), as this is the prevalent species between domestic Triatomidae in the region; 3 Panstrongylus megistus were found in one house and 329 of them were captured in a chicken-house, a few of which were examined and found negative. 5) From 68 houses whose dogs or cats have been conclusively examined we found 22 with at least one of those animals infccted by T. cruzi (32.35%).