Abstract
In two Ecuadorian endemic areas of Chagas' disease, Pedro Carbo in coastal low-land and Zaruma in high-land of the Andes, a seroepidemiological survey of the human infection and a search for reservoir hosts were performed during the period between June 1983 and March 1984.
Indirect hemaggultination (IHA) test-positive rate of inhabitants was 4.3 per cent (10/233) in Pedro Carbo, and 15.5 per cent (67/433) in Zaruma. The positive rate of high school students was 2.2 per cent (10/446) and 3.9 per cent (12/305) in each area, respectively.
Trypanosoma cruzi was found in two species of peridomestic mammals, Didelphis marsupialis (opossum) and Dasypus novemcinctus (armadillo). The infection rate of D. marsupialis was 25.0 per cent (17/68) in Pedro Carbo and 18.5 per cent (5/27) in Zaruma. Only one of the 70 babies from pouch of D. marsupialis examined was found to be positive for T. cruzi, though the mother and the other litter mates were negative for the flagellata. One of four D. novemcinctus was positive for the parasite in Zaruma. No trypanosome was recognized in all the rodents and bats examined. The result suggests that D. marsupialis is the principal reservoir host of Chagas' disease in various endemic areas of Ecuador.
