BACKGROUND The
Trypanosoma cruzi infection endemic in
Latin America has now spread to several countries across four continents; this endemic involves triatomine vector-free protists. We hypothesised that the sexual
transmission of T. cruzi contributes to the ongoing spread of
Chagas disease . OBJECTIVES A short-term
longitudinal study was conducted to evaluate this hypothesis.
METHODS The study
population comprised 109 subjects from four
families , among whom 21 had been diagnosed with acute
Chagas disease by direct
parasitological analysis .
Blood mononuclear
cells and
serum samples were obtained from each study subject once per year for three consecutive years.
Enzyme-linked immunosorbent assay (
ELISA ) and
indirect immunofluorescence serological examinations were used to detect specific T. cruzi
antibodies .
Polymerase chain reaction of T. cruzi
DNA revealed 188-
nucleotide bands, which hybridised to a specific radiolabelled probe and were confirmed by
cloning and sequencing. RESULTS Three independent assessments at different
time points revealed T. cruzi nuclear
DNA footprints in 76% (83/109) of the study
population with active
infection . In contrast, the
ELISA and
indirect immunofluorescence assays detected the T. cruzi antibody in 28.4% (31/109) of the study samples. Moreover, the
semen from 82.6% (19/23) of subjects people revealed harboured the 188- bp
base pair T. cruzi footprint. Interestingly, the ejaculates of nuclear
DNA -positive Chagas
patient transmitted the T. cruzi upon peritoneal
injection or infusion in the
vagina of
mice , and amastigotes were detected in the
skeletal muscle ,
myocardium ,
vas deferens , and
uterine tube . MAIN CONCLUSIONS T. cruzi
infections can be transmitted from
females or
males to naïve mates through intercourse, and progeny showed discrepancies between the ratios of nuclear
DNA footprints and specific antibody that can be explained by the tolerance attained during early
embryo growth . Additional studies are needed to develop
drugs to eradicate the
infections . Additionally, the importance of a vigorous
education , information, and
communication program to prevent sexually transmitted
Chagas disease in
humans cannot be underemphasized