Nwoya District Local Government, Nwoya, Uganda.
Center for Global Health Infectious Disease Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America.
PLoS Negl Trop Dis. 2019 Jul 16;13(7):e0007558. doi: 10.1371/journal.pntd.0007558. eCollection 2019 Jul.
Onchocerciasis, or river blindness, has historically been an important cause of blindness, skin disease and economic disruption in Africa and the Americas. It is caused by the filarial parasite Onchocerca volvulus, which is transmitted by black flies in the genus Simulium. Over the past decade, several international programs have been formed to control, or more recently eliminate onchocerciasis, using mass drug administration (MDA) of ivermectin. However, in many areas of Africa (particularly those which are endemic for the eyeworm, Loa loa, or where vector densities are very high) ivermectin MDA alone will not be sufficient to achieve elimination. In these situations, additional interventions may be necessary.
METHODOLOGY/PRINCIPAL FINDINGS: The Esperanza Window trap (EWT), a simple trap originally developed to replace human landing collections for entomological surveillance of O. volvulus transmission was optimized, resulting in a 17-fold improvement in trap performance. The optimized trap was tested in trials in schools and in agricultural fields to determine if it could reduce vector biting locally. The traps resulted in a 90% reduction in biting in the school setting. In the field setting, results varied. In one location, the traps reduced biting by roughly 50%, while in a separate trial, the traps did not significantly reduce the biting rate. Examination of the two settings suggested that trap placement may be critical to their success.
CONCLUSIONS/SIGNIFICANCE: These results suggest that the optimized EWT might be capable of reducing local vector black fly biting in areas commonly frequented by residents. Together with other recently developed methods of community directed vector control, the traps may augment ivermectin MDA, bringing the goal of onchocerciasis elimination within reach in much of Africa.
盘尾丝虫病，或河盲症，曾是非洲和美洲重要的致盲、皮肤病和经济破坏原因。它由盘尾丝虫属的寄生虫引起，由蚋属中的黑蝇传播。在过去十年中，已成立了几个国际项目，以利用伊维菌素的大规模药物治疗（MDA）来控制或最近消除盘尾丝虫病。然而，在非洲的许多地区（特别是那些眼部蠕虫（Loa loa）流行或媒介密度非常高的地区），单独使用伊维菌素 MDA 不足以实现消除。在这些情况下，可能需要额外的干预措施。
方法/主要发现： Esperanza 窗口陷阱（EWT）是一种简单的陷阱，最初是为了代替人类着陆收集，用于 O. volvulus 传播的昆虫学监测而开发的，对其进行了优化，使陷阱性能提高了 17 倍。优化后的陷阱在学校和农业领域的试验中进行了测试，以确定它是否可以在当地减少媒介叮咬。结果显示，在学校环境中，陷阱导致叮咬减少了 90%。在田间环境中，结果有所不同。在一个地点，陷阱将叮咬率降低了约 50%，而在另一个单独的试验中，陷阱并没有显著降低叮咬率。对这两个环境的检查表明，陷阱的放置可能对其成功至关重要。
结论/意义：这些结果表明，优化后的 EWT 可能有能力减少居民常去的地区的当地媒介黑蝇叮咬。与最近开发的其他社区定向性控制媒介方法一起，这些陷阱可能会增强伊维菌素 MDA 的效果，使非洲大部分地区实现消除盘尾丝虫病的目标成为可能。
