Native and non-native antigen to determine the seroprevalence of Trypanosoma cruzi in pregnant women from the state of Morelos, Mexico

Background: Chagas disease is a globally important chronic systemic parasitic infection caused by Trypanosoma cruzi. Aim: To determine the prevalence of antibodies against T. cruzi in pregnant women front the state of Morelos, Mexico. Methods: 1,620 sera from pregnant women were analyzed using two serological tests: ELISAc (native crude antigen) and ELISAr (recombinant, non-native antigen). Reactive samples were subsequently analyzed by indirect hemagglutination (IHA). Two detection approaches were used, in parallel (reactive samples by any method are positive) and serial (samples confirmed by IHA are positive). Sociodemographic and health factors associated with the presence of antibodies against T. cruzi were evaluated using 95% odds ratios. Results: A seroprevalence of 4.87% was obtained with parallel diagnosis and 0.43% in series. From the parallel results, the women who were attended at the general hospitals of Tetecala and Jojutla had respectively 2.2 and 2.0 times greater chance of presenting antibodies against T. cruzi compared to the women who were attended at the General Hospital of Cuautla. Conclusion: The prevalence of antibodies against T. cruzi in pregnant women from the state of Morelos fluctuated between 0.43 and 4.87%, depending on the antigen and the approach used. It is necessary to continue with the surveillance of the seroprevalence of antibodies against T. cruzi in pregnant women from the state of Morelos, Mexico, using the techniques with the highest sensitivity and specificity available.