Gorla David Eladio, Ortiz Roberto Vargas, Catalá Silvia Susana
Centro Regional de Investigaciones Científicas y Transferencia Tecnológica. CRILAR-CONICET, 5201, Anillaco, La Rioja, Argentina.
Programa Chagas, Servicio Departamental de Salud, Santa Cruz de la Sierra, Bolivia.
Parasit Vectors. 2015 May 1;8:255. doi: 10.1186/s13071-015-0762-0.
Triatoma infestans, the main vector of Trypanosoma cruzi (causative agent of Chagas disease) has been successfully eliminated over much of its original geographic distribution over the southern cone countries of South America. However, populations of the species are still infesting houses of rural communities of the Gran Chaco region of Argentina and Bolivia. This study reports for the first time a large-scale effect of a vector control intervention using a microencapsulated formulation of organophosphates and insect growth regulator on house infestation by T. infestans, in the southwestern region of Santa Cruz de la Sierra Department, within the Bolivian chaco.
The vector control intervention included the treatment and entomological evaluation of 1626 individually coded and georeferenced houses with the microencapsulated formulation. House infestation by T. infestans was evaluated by active searches with fixed capture effort carried out before and after two, 16 and 32 months of the treatment application.
House infestation prevalence was 30.5% before the intervention, spatially aggregated in two clusters of 38 and 25 localities that showed 41% and 38% house infestation by T. infestans. Infestation prevalence was reduced to 2.4% two months after the intervention and remained very low (1.7%) until the end of the study after 32 months of the control intervention, without any other additional vector control intervention.
The obtained results show an important long lasting effect on house protection against triatomine infestation in a region of known pyrethroid resistant populations of T. infestans, as the result of the slow release of the active ingredients, protected by the formulation microcapsule.
克氏锥虫（恰加斯病的病原体）的主要传播媒介——骚扰锥猎蝽，已在南美洲南锥体国家的大部分原始地理分布区域成功消灭。然而，该物种的种群仍在阿根廷和玻利维亚大查科地区的农村社区房屋中滋生。本研究首次报告了在玻利维亚查科地区圣克鲁斯德拉谢拉省西南部，使用微囊化有机磷和昆虫生长调节剂制剂进行病媒控制干预对骚扰锥猎蝽房屋滋生的大规模影响。
病媒控制干预包括用微囊化制剂对1626所单独编码并进行地理定位的房屋进行处理和昆虫学评估。通过在处理应用前、处理后2个月、16个月和32个月进行固定捕获工作量的主动搜索，评估骚扰锥猎蝽对房屋的侵扰情况。
干预前房屋侵扰率为30.5%，在两个分别有38个和25个地点的集群中呈空间聚集，这些地点显示骚扰锥猎蝽对房屋的侵扰率分别为41%和38%。干预2个月后侵扰率降至2.4%，在32个月的对照干预结束直至研究结束时一直维持在很低水平（1.7%），期间未进行任何其他额外的病媒控制干预。
所获结果表明，在已知存在对拟除虫菊酯耐药的骚扰锥猎蝽种群的地区，由于活性成分通过制剂微胶囊得到保护而缓慢释放，该干预措施对房屋免受锥猎蝽侵扰具有重要的长期效果。
