Briët Olivier J T, Yukich Joshua O, Pfeiffer Constanze, Miller William, Jaeger Mulako S, Khanna Nitin, Oppong Samuel, Nardini Peter, Ahorlu Collins K, Keating Joseph
Swiss Tropical and Public Health Institute, Basel, Switzerland.
University of Basel, Basel, Switzerland.
Malar J. 2017 Jan 3;16(1):12. doi: 10.1186/s12936-016-1654-2.
Long-lasting insecticidal nets (LLINs) are ineffective malaria transmission prevention tools if they are unused. Discomfort due to heat is the most commonly reported reason for not using nets, but this problem is largely unaddressed. With increasing rural electrification and the dropping price of solar power, fans could improve comfort inside nets and be affordable to populations in malaria endemic areas. Here, results are presented from a pilot randomized controlled cross-over study testing the effect of fans on LLIN use.
Eighty-three households from two rural communities in Greater Accra, Ghana, randomized into three groups, participated in a 10-month cross-over trial. After a screening survey to identify eligible households, all households received new LLINs. Bͻkͻͻ net fan systems (one fan per member) were given to households in Group 1 and water filters were given to households in Group 2. At mid-point, Group 1 and 2 crossed over interventions. Households in Group 1 and 2 participated in fortnightly surveys on households' practices related to nets, fans and water filters, while households in Group 3 were surveyed only at screening, mid-point and study end. Entomological and weather data were collected throughout the study. Analysis took both 'per protocol' (PP) and 'intention to treat' (ITT) approaches. The mid- and end-point survey data from Group 1 and 2 were analysed using Firth logistic regressions. Fortnightly survey data from all groups were analysed using logistic regressions with random effects.
Provision of fans to households appeared to increase net use in this study. Although the increase in net use explained by fans was not significant in the primary analyses (ITT odds ratio 3.24, p > 0.01; PP odds ratio = 1.17, p > 0.01), it was significant in secondary PP analysis (odds ratio = 1.95, p < 0.01). Net use was high at screening and even higher after provision of new LLINs and with follow up. Fan use was 90-100% depending on the fortnightly visit.
This pilot study could not provide definitive evidence that fans increase net use. A larger study with additional statistical power is needed to assess this association across communities with diverse environmental and socio-demographic characteristics.
如果长效驱虫蚊帐（LLINs）不使用，它们就是无效的疟疾传播预防工具。因炎热导致的不适是最常被报告的不使用蚊帐的原因，但这个问题在很大程度上未得到解决。随着农村电气化程度的提高和太阳能价格的下降，风扇可以改善蚊帐内的舒适度，并且疟疾流行地区的人群也能够负担得起。本文展示了一项试点随机对照交叉研究的结果，该研究测试了风扇对长效驱虫蚊帐使用的影响。
来自加纳大阿克拉两个农村社区的83户家庭被随机分为三组，参与了一项为期10个月的交叉试验。在进行筛选调查以确定符合条件的家庭后，所有家庭都收到了新的长效驱虫蚊帐。第1组家庭获得了Bͻkͻͻ蚊帐风扇系统（每个成员一个风扇），第2组家庭获得了滤水器。在试验中期，第1组和第2组交叉干预措施。第1组和第2组家庭每两周参与一次关于家庭与蚊帐、风扇和滤水器相关做法的调查，而第3组家庭仅在筛选、中期和研究结束时接受调查。在整个研究过程中收集了昆虫学和天气数据。分析采用了“符合方案”（PP）和“意向性分析”（ITT）两种方法。使用Firth逻辑回归分析第1组和第2组的中期和终点调查数据。使用具有随机效应的逻辑回归分析所有组每两周的调查数据。
在本研究中，向家庭提供风扇似乎增加了蚊帐的使用。尽管在主要分析中，风扇导致的蚊帐使用增加并不显著（ITT优势比为3.24，p>0.01；PP优势比=1.17，p>0.01），但在次要PP分析中显著（优势比=1.95，p<0.01）。在筛选时蚊帐使用率很高，在提供新的长效驱虫蚊帐并进行随访后更高。根据每两周的访问情况，风扇使用率为90%-100%。
这项试点研究无法提供确凿证据证明风扇能增加蚊帐的使用。需要进行一项具有更大统计效力的更大规模研究，以评估不同环境和社会人口特征社区之间的这种关联。
