Serological and parasitological screening of Trypanosoma cruzi infection in mothers and newborns living in two Chagasic areas of Mexico.

BACKGROUND: Maternal-fetal transmission of Trypanosoma cruzi generally occurs in 2-12% of pregnant infected mothers. This transmission form has been poorly studied in Mexico where only one case of congenital infection published in 1998 has been reported. METHODS: We screened 145 mothers and their delivered babies in two hospitals of endemic regions in Mexico (states of Chiapas and Veracruz) searching for anti-T. cruzi antibodies and circulating parasites by hemoculture and PCR. RESULTS: In Poza Rica, Veracruz, 3/85 (3.5%) mothers were seropositive for T. cruzi infection and in Palenque, Chiapas, 3/60 (5%) cases. In total 6/145 (4.1%) were seropositive subjects. Although cord blood samples of delivered babies from seropositive mothers have IgG anti-T. cruzi antibodies, none presented PCR and positive hemoculture. CONCLUSIONS: Although a high relative seroprevalence of T. cruzi infection in pregnant women was detected, no case of vertical transmission was recognized. Undoubtedly, further studies of large samples are necessary to evaluate maternal transmission risk in Mexico.