Blood transfusion is the second
most common transmission route of Chagas disease in many Latin American countries.
In Mexico, the prevalence of Chagas disease and impact of transfusion of
Trypanosoma cruzi
-contaminated blood is not clear. We determined the seropositivity
to
T. cruzi in a representative random sample, of 2,140 blood donors (1,423
men and 647 women, aged 19-65 years), from a non-endemic state of almost 5 millions
of inhabitants by the indirect hemagglutination (IHA) and enzyme linked immunosorbent
assay (ELISA) tests using one autochthonous antigen from
T. cruzi parasites,
which were genetically characterized like TBAR/ME/1997/RyC-V1 (
T. cruzi
I) isolated from a
Triatoma barberi
specimen collected in the
same locality. The seropositivity was up to 8.5% and 9% with IHA and ELISA tests,
respectively, and up to 7.7% using both tests in common. We found high seroprevalence
in a non-endemic area of Mexico, comparable to endemic countries where the disease
occurs, e.g. Brazil (0.7%), Bolivia (13.7%) and Argentina (3.5%). The highest
values observed in samples from urban areas, associated to continuous rural emigration
and the absence of control in blood donors, suggest unsuspected high risk of transmission
of
T. cruzi, higher than those reported for infections by blood e.g. hepatitis
(0.1%) and AIDS (0.1%) in the same region.
