Chagas Disease

Chagas disease, also called American Trypanosomiasis, is one of the most prominent vector-borne diseases in Latin America. It is caused by the protozoan parasite, Trypanosoma cruzi, and transmitted by blood-feeding triatomine bugs. Infection occurs not by the biting of the bugs, but by infiltration of the feces of infected bugs during blood feeding.

In rural areas of Argentina, for example, most people acquire infection in their homes because the cracks in the walls of their houses and the thatched roofs under which people live tend to be shelters for triatomine bugs. Furthermore, domestic and peridomestic animals, such as dogs and chickens, often occupy people’s bedrooms, thus providing sufficient blood sources for the bugs. Human-to-human transmission is generally impossible, but a few infants are infected by their mothers, who already have Chagas disease, and in rare cases people can contract Chagas disease through blood transfusions. Because of the central role of animal-to-human transmission, more focus on Trypanosomiasis infestans as a main vector of the Chagas disease in domestic housing of Argentina1 is expected, even though many species of triatomine bugs transmit Trypanosomiasis cruzi throughout the geographic region.

Currently, neither vaccine nor prophylaxis is available.An effective drug treatment is used for humans only in the acute and early chronic phase of infection. People cannot develop immunity for Chagas disease even after recovering from the infection.

Possible control measures for Chagas disease are 1) improving housing, 2) annual spraying of insecticides and killing of triatomine bugs, 3) providing early prevention for infants born to infected mothers through congenital surveillance and treatment of infected infants, 4) excluding reservoir animals from human housing, and 5) blood screening.