Peridomestic structure, farming activity and triatomine infestation.

The role of peridomestic structure and farming activity on triatomine infestation was studied on two vector species of Chagas disease (Triatoma pseudomaculata and T. brasiliensis) in Bahia State, northeastern Brazil. A randomly selected population issued from 136 farms was divided into four categories according to the householder activity. At regional scale, the dwellings of farmers working on degraded land of irrigated farms are less exposed to T. pseudomaculata infestation. At premises scale, the farmers and casual workers, who have smaller peridomiciles and less cattle, are also less exposed to T. pseudomaculata. The association of T. brosiliensis with the most mobile populations (casual workers and young breeders) suggests a passive transport of this competitive species. Finally, the retired farmers that own large premises and cattle, but have more sedentary behavior, are the most exposed to T. pseudomaculata infestation.