Bednet impregnation for Chagas disease control: a new perspective.

The impregnation of bednets has proved effective in reducing malaria mortality and morbidity in Africa and Latin America. Such bednet impregnation to control Chagas disease vectors would have many advantages. Findings are presented from a study conducted in Norte de Santander Santander and Antioquia 3 endemic departments of Colombia to examine peoples views about Chagas disease and its vectors the acceptability of bednet impregnation and the efficacy of bednet impregnation in killing Chagas disease transmitting vectors. Participant interviews and direct observation found Chagas disease to be little known in the study communities even in areas where research and control operations had been conducted in previous years. Interviewees were however disgusted with the responsible vector and believed it to transmit cutaneous leishmaniasis. In the entomological component of the study 20 laboratory-bred Chagas vectors (Rhodnius prolixus) were released for each of 5 nights in an experimental room with the human bait protected for 1 night by an unimpregnated bednet and for 4 nights by a deltamethrin-impregnated bednet (at the concentration of 13 mg/sq. m). Vectors were stained with fluorescent powder for observation collected after 10 hours exposure in the experimental room and observed for another 72 hours. The resulting vector mortality rates were 95% in the room with impregnated nets and 10% in the room with unimpregnated nets.