Entomological aspects of an ecological study on domestic T. cruzi transmission carried out in a rural community of Argentina are described. T. cruzi infection rates an d the feeding profiles of domiciliary T. infestans were determined, and bug density was related to house construction. Six of 18 houses studied were new and reformed while 16 households hexachlorocyclohexane (HCH) had been used by the inmates. The lowest bug densities were found in new houses or those receiving good, insecticide treatment. Insecticide treated units had an a verage number of bugs 10 times lower(3.1 bugs/man-hour) than thosefound in a non treated ones indicating the effectiveness of selfp romoted control. A ll bedrooms but only 53% o f peridomestic structures harboured bugs. T. cruzi infection was detected in 39% of domiciliary. T. infestans 96% of the domiciliary bugs (9 6% ) f e d on man, dog, chicken and cat. The affinity index fo r dog was 13 times higher than that for man. The importance of the high density of T. infestans bugs in bedrooms and their close association with "roommate ” dogs is discussed in relation to transmission as well as the need to combine house improvement and health education programmes.
Triatomines, Feeding profile; Control; T. cruzi transmission