Peridomestic colonization of Triatoma longipennis (Hemiptera, Reduviidae) and Triatoma barberi (Hemiptera, Reduviidae) in a rural community with active transmission of Trypanosoma cruzi in jalisco state, Mexico

Infestation of peridomiciles is likely a major risk factor for Chagas disease transmission in Jalisco state, Mexico. An entomological and serological survey of a typical village was conducted between July and September 2003. The peridomestic areas of 100 dwellings were visited and triatomines were searched manually in 369 potential sites. A total of 1821 Triatoma longipennis (93.2%) or Triatoma barberi was captured. Both species frequently occurred in sympatry. The infestation index was 60% for T. longipennis and 16% for T. barberi. T. longipennis occurred throughout the village. Colonization indices were high for T. longipennis (93%) and T. barberi (75%), suggesting that both species have adapted to peridomestic habitats. The bug population size was larger for T. longipennis than for T. barberi. Five very large colonies of T. longipennis were recorded whereas only 1 or 2 bugs were observed in 38% of the positive sites, which suggests intense dispersal activity. Both species exhibited high infection prevalence with Trypanosoma cruzi (46%). Only T. cruzi lineage I was detected. Human seroprevalence was 1.8%. This study serves as an entomological overview of peridomiciliar triatomine colonization in a Mexican village and highlights the current risk of Chagas disease transmission.