期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2022
卷号：119
期号：26
DOI：10.1073/pnas.2118283119
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Significance
Vector interventions are needed for
Aedes-borne viral (ABV) disease prevention (dengue, Zika, chikungunya, and yellow fever), but their application is hindered by the lack of evidence proving they prevent infection or disease. We report conclusive statistical evidence from a pre-planned, prospective cluster-randomized, controlled clinical trial (cRCT) of protective efficacy (34.1% hazard estimate) against human ABV infection by a spatial repellent; a chemical-based intervention category currently under World Health Organization review. Results from our ABV study will help guide public health authorities responsible for operational management and worldwide ABV disease control and incentivize new strategies for disease prevention.
Over half the world’s population is at risk for viruses transmitted by
Aedes mosquitoes, such as dengue and Zika. The primary vector,
Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of
Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to
Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito–human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare
Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided
P value = 0.0236, z = 1.98).
Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = −9.11) and 12.4% (95% CI 4.2%, ∞);
z = −2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.
