Olukayode G Odufuwa, Sarah Jane Moore, Zawadi Mageni Mboma, Rehema Mwanga, Fatuma Matwewe, Lorenz Martin Hofer, Isaya Matanila, Said Abbasi, Mohammed Ally Rashid, Rose Philipo, Fadhila Kihwele, Jason Moore, Hien Nguyen, Rune Bosselmann, Ole Skovmand, Jennifer C Stevenson, Joseph B Muganga, John Bradley
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引用次数: 0
Abstract
Background: Installing insecticidal netting on open eaves, windows, and holes in walls of unimproved houses is a potential malaria control tool. It prevents mosquito house-entry, induces lethal and sub-lethal effects on malaria vectors, and may reduce malaria transmission. Therefore, a household epidemiological trial was conducted to assess the efficacy of insecticide-treated screening (ITS) on malaria infection and indoor vectors in Tanzania.
Methods: In Chalinze district, Tanzania, 421 households were randomized into two arms. In June-July 2021, one group of households' houses was fitted with ITS (incorporated with deltamethrin and piperonyl butoxide) on eaves, windows, and wall holes, while the second group did not receive screening. After installation, consenting household members (aged ≥ 6 months) were tested for malaria infection using quantitative polymerase chain reaction after the long rainy season (June/July 2022, primary outcome) and the short rainy season (January/February 2022, secondary outcome). Secondary outcomes included indoor total mosquito per trap/night (June-July 2022), adverse effects after one month of ITS installation (August 2021), and chemical bioavailability and retention of ITS samples after one year of field use (June/July 2022). At the end of the trial, the control group received ITS.
Results: Malaria prevalence among residents in the ITS arm was 19.9% (50/251) and 28.3% (65/230) in the control arm after the long rains, however, this difference was not significant [adjusted odds ratio (OR) 0.67 (95% CI 0.35-1.28), p = 0.227]. Similarly, no protection was seen for ITS after the short rains, [OR 1.27 (95% CI 0.68-2.38), p = 0.452]. However, school-age children in the ITS arm had lower malaria after the long rains [OR 0.11 (95% CI 0.02-0.73), p = 0.022]. No serious adverse effects were reported. The mean number of female Anopheles mosquitoes caught per trap/night was not significantly different between arms [1.7 vs 2.4, crude relative risk: 0.71 (95% CI 0.16-3.09), p = 0.650]. ITS showed reduced chemical bioavailability and retention post-field use. The trial reported high household refusals (17-30%) in both arms in both surveys.
Conclusion: The trial was inconclusive because households' refusal resulted in low power. A large cluster randomized trial of the intervention, preferably with screens treated with longer-lasting insecticides installed in houses, is needed.
Trial registry: The trial was registered at ClinicalTrials.gov (NCT05125133) on October 2021.
背景：在未经改善的房屋开放的屋檐、窗户和墙上的洞上安装杀虫网是一种潜在的疟疾控制工具。它可以防止蚊子进入室内，对疟疾病媒产生致死和亚致死作用，并可能减少疟疾传播。因此，进行了一项家庭流行病学试验，以评估坦桑尼亚杀虫剂处理筛查（ITS）对疟疾感染和室内媒介的效果。方法：在坦桑尼亚Chalinze地区，将421户家庭随机分为两组。2021年6月至7月，一组家庭的房屋在屋檐、窗户和墙孔上安装了ITS（含有溴氰菊酯和胡椒酰丁醇），而第二组没有接受筛选。安装后，在长雨季（2022年6月/ 7月，主要结局）和短雨季（2022年1月/ 2月，次要结局）之后，使用定量聚合酶链反应对同意的家庭成员（年龄≥6个月）进行疟疾感染检测。次要结果包括室内每个诱蚊器/夜蚊总数（2022年6月至7月），ITS安装一个月后的不良影响（2021年8月），以及ITS样品在现场使用一年后的化学生物利用度和保留率（2022年6月至7月）。在试验结束时，对照组接受ITS治疗。结果：长雨后ITS组居民疟疾患病率为19.9%(50/251)，对照组居民疟疾患病率为28.3%(65/230)，但差异不显著[校正优势比（OR） 0.67 (95% CI 0.35-1.28), p = 0.227]。同样，短时降雨后ITS也没有保护作用，[OR 1.27 (95% CI 0.68-2.38), p = 0.452]。然而，ITS组的学龄儿童在长时间降雨后的疟疾发病率较低[OR 0.11 (95% CI 0.02-0.73), p = 0.022]。没有严重的不良反应报告。每个诱蚊器/夜平均捕获雌按蚊数各组间差异无统计学意义[1.7 vs 2.4，粗相对危险度：0.71 (95% CI 0.16-3.09), p = 0.650]。ITS显示田间使用后化学生物利用度和保留率降低。该试验在两次调查中都报告了较高的家庭拒绝率（17-30%）。结论：试验结果不确定，因为住户的拒绝导致了低功率。需要对该干预措施进行大规模的集群随机试验，最好是在室内安装用长效杀虫剂处理过的屏风。试验注册：该试验于2021年10月在ClinicalTrials.gov （NCT05125133）注册。
期刊介绍：
Malaria Journal is aimed at the scientific community interested in malaria in its broadest sense. It is the only journal that publishes exclusively articles on malaria and, as such, it aims to bring together knowledge from the different specialities involved in this very broad discipline, from the bench to the bedside and to the field.
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