Orally Acquired Chagas Disease: Lessons from an Urban School Outbreak

Extract

The protozoan pathogen Trypanosoma cruzicauses Chagas disease, one of the most important parasitic infections in Latin America. Without effective treatment, infection is usually for life. A likely outcome of infection is heart disease, with electrocardiogram abnormalities and cardiomyopathy. In some geographical areas, this may be complicated by megasyndromes, particularly megaesophagus and megacolon [1].

The insect vectors are blood-sucking triatomines. Transmission occurs when insects feed, but the route is precarious and indirect, by contamination of mucous membranes or abraded skin with T. cruzi-infected triatomine feces. The main culprit vectors are a few triatomine species that colonize poor rural dwellings and feed from the inhabitants and from their domestic animals. Despite the recent success of international programs to control such domestic triatomines (notably, Triatoma infestansin the Southern Cone countries of South America), wide regions of domestic transmission remain. Furthermore, T. cruziis a zoonosis; there are many mammal reservoir hosts (such as opossums, armadillos, and rodents), and many triatomine species act as vectors in sylvatic habitats. Such sylvatic bugs pose a threat by replenishing household colonies or by new adaptations to domestic habitats, as well as by occasional incursion of adult insects that fly into houses and may cause sporadic cases of Chagas disease.