Seroprevalence of Trypanosoma cruzi in household and shelter dogs in the northeastern region of Brazil

Dogs play a crucial role as peri-domestic reservoirs and potential sentinels in the environmental circulation of Trypanosoma cruzi. However, despite their relevance to One Health, seroepidemiological studies on the distribution of T. cruzi in dogs remain scarce. Thus, this study aimed to determine the frequency of anti-T. cruzi IgG antibodies in household and shelter dogs in the municipality of Arapiraca, Alagoas, in the northeastern region of Brazil. Serum samples from 150 dogs from two shelters and 150 from household dogs were tested for IgG anti-T. cruzi antibodies using the Immunofluorescent Antibody Test (IFAT) (cut-off ≥ 1:40). Univariate analysis was employed to investigate factors associated with seropositivity for the parasite. Of the animals, 9.0% (27/300) tested positive for anti-T. cruzi antibodies. Shelter dogs (frequency = 77.8%; 21/27) exhibited an odds ratio (OR) = 3.29 (95% CI [1.25 - 8.64]; p = 0.0156) compared to household dogs (frequency = 22.2%; 6/27). The results of this study indicate that shelter dogs are more exposed to the infection and can be used as sentinel animals in local Chagas disease control programs to predict the emergence of cases in human populations.