Database Reference
In-Depth Information
Chapter 6
Chagas Disease
Chagas disease, also called American Trypanosomiasis, is one of the most promi-
nent vector-borne diseases in Latin America. It is caused by the protozoan para-
site,
Trypanosoma cruzi
, and transmitted by blood-feeding triatomine bugs. Infec-
tion 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 Argentina
1
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) an-
nual spraying of insecticides and killing of triatomine bugs, 3) providing early pre-
vention 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.
1
Cecere, M.C., Castanera, M.B., Canale, D.M., Chuit, R. and E. Gurtler. 1999.
Trypanosoma
cruzi
infection in Triatoma infestans and other triatomines: long-term effects of a control program
in rural northwestern Argentina. Pan Am J Public Health, 5(6), 392-399.
