Entomological aspects of Chagas' disease transmission in the domestic habitat, Argentina
Catalá, S.S.; Crocco, L.B.; Muñoz, A.; Morales, G.; Paulone, I.; Giraldez, E.; Candioti, C.; Ripol, C.
Revista de Saude Publica 38(2): 216-222
2004
ISSN/ISBN: 0034-8910 PMID: 15122377 DOI: 10.1590/s0034-89102004000200010Document Number: 242014
Objective: To study the risk of Trypanosoma cruzi domestic transmission using an entomological index and to explore its relationship with a household's characteristics and cultural aspects. Methods: 158 households in an endemic area in Argentina were included in the study. Each household was classified according to an entomological risk indicator (number of risky bites/human). A questionnaire was administered to evaluate risk factors among householders. Results: Infested households showed a wide range of risk values (0 to 5 risky bites/human) with skewed distribution, a high frequency of lower values and few very high risk households. Of all collected Triatoma infestans, 44% had human blood meals whereas 27% had dog or chicken blood meals. Having dogs and birds share a room with humans increased the risk values. Clean households had contributed significantly to lower risk values as a result of low vector density. The infested households showed a 24.3% correlation between time after insecticide application and the number of vectors. But there was no correlation between the time after insecticide application and T. infestans' infectivity. The statistical analysis showed a high correlation between current values of the entomological risk indicator and Trypanosoma cruzi seroprevalence in children. Conclusions: The risk of T. cruzi domestic transmission, assessed using an entomological index, show a correlation between the seroprevalence of Chagas' disease in children and householders' habits.