Kroeger Axel, Lenhart Audrey, Ochoa Manuel, Villegas Elci, Levy Michael, Alexander Neal, McCall P J
Special Programme for Research and Training in Tropical Medicine (TDR/WHO), World Health Organization, Geneva, Switzerland.
BMJ. 2006 May 27;332(7552):1247-52. doi: 10.1136/bmj.332.7552.1247.
To measure the impact on the dengue vector population (Aedes aegypti) and disease transmission of window curtains and water container covers treated with insecticide.
Cluster randomised controlled trial based on entomological surveys and, for Trujillo only, serological survey. In addition, each site had a non-randomised external control.
18 urban sectors in Veracruz (Mexico) and 18 in Trujillo (Venezuela).
4743 inhabitants (1095 houses) in Veracruz and 5306 inhabitants (1122 houses) in Trujillo.
Sectors were paired according to entomological indices, and one sector in each pair was randomly allocated to receive treatment. In Veracruz, the intervention comprised curtains treated with lambdacyhalothrin and water treatment with pyriproxyfen chips (an insect growth regulator). In Trujillo, the intervention comprised curtains treated with longlasting deltamethrin (PermaNet) plus water jar covers of the same material. Follow-up surveys were conducted at intervals, with the final survey after 12 months in Veracruz and nine months in Trujillo.
Reduction in entomological indices, specifically the Breteau and house indices.
In both study sites, indices at the end of the trial were significantly lower than those at baseline, though with no significant differences between control and intervention arms. The mean Breteau index dropped from 60% (intervention clusters) and 113% (control) to 7% (intervention) and 12% (control) in Veracruz and from 38% to 11% (intervention) and from 34% to 17% (control) in Trujillo. The pupae per person and container indices showed similar patterns. In contrast, in nearby communities not in the trial the entomological indices followed the rainfall pattern. The intervention reduced mosquito populations in neighbouring control clusters (spill-over effect); and houses closer to treated houses were less likely to have infestations than those further away. This created a community effect whereby mosquito numbers were reduced throughout the study site. The observed effects were probably associated with the use of materials treated with insecticide at both sites because in Veracruz, people did not accept and use the pyriproxyfen chips.
Window curtains and domestic water container covers treated with insecticide can reduce densities of dengue vectors to low levels and potentially affect dengue transmission.
评估用杀虫剂处理的窗帘和盛水容器盖对登革热媒介种群（埃及伊蚊）及疾病传播的影响。
基于昆虫学调查的整群随机对照试验，仅在特鲁希略进行了血清学调查。此外，每个地点都有一个非随机的外部对照。
墨西哥韦拉克鲁斯的18个城市区域和委内瑞拉特鲁希略的18个城市区域。
韦拉克鲁斯的4743名居民（1095户家庭）和特鲁希略的5306名居民（1122户家庭）。
根据昆虫学指标将各区域配对，每对中的一个区域随机分配接受处理。在韦拉克鲁斯，干预措施包括用高效氯氟氰菊酯处理的窗帘以及用吡丙醚片（一种昆虫生长调节剂）进行水处理。在特鲁希略，干预措施包括用长效溴氰菊酯（PermaNet）处理的窗帘以及相同材料的水缸盖。定期进行随访调查，韦拉克鲁斯在12个月后、特鲁希略在9个月后进行了最终调查。
昆虫学指标的降低，特别是布雷托指数和房屋指数。
在两个研究地点，试验结束时的指标均显著低于基线水平，但对照组和干预组之间无显著差异。在韦拉克鲁斯，平均布雷托指数从60%（干预组）和113%（对照组）降至7%（干预组）和12%（对照组），在特鲁希略从38%降至11%（干预组），从34%降至17%（对照组）。人均蛹数和容器指数呈现相似模式。相比之下，未参与试验的附近社区的昆虫学指标随降雨模式变化。干预措施减少了邻近对照区域的蚊虫数量（溢出效应）；与距离较远的房屋相比，距离处理过的房屋较近的房屋蚊虫滋生的可能性较小。这产生了一种社区效应，使整个研究地点的蚊虫数量减少。观察到的效果可能与两个地点使用杀虫剂处理的材料有关，因为在韦拉克鲁斯，人们不接受并使用吡丙醚片。
用杀虫剂处理的窗帘和家用盛水容器盖可将登革热媒介密度降低到低水平，并可能影响登革热传播。
