评估驱虫处理凉鞋对坦桑尼亚东南部蚊虫叮咬的个人防护作用。

Evaluation of personal protection afforded by repellent-treated sandals against mosquito bites in south-eastern Tanzania.

机构信息

Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania.

International Centre for Insect Physiology and Ecology, Nairobi, Kenya.

出版信息

Malar J. 2020 Apr 8;19(1):148. doi: 10.1186/s12936-020-03215-7.

BACKGROUND

Outdoor and early evening mosquito biting needs to be addressed if malaria elimination is to be achieved. While indoor-targeted interventions, such as insecticide-treated nets and indoor residual spraying, remain essential, complementary approaches that tackle persisting outdoor transmission are urgently required to maximize the impact. Major malaria vectors principally bite human hosts around the feet and ankles. Consequently, this study investigated whether sandals treated with efficacious spatial repellents can protect against outdoor biting mosquitoes.

METHODOLOGY

Sandals affixed with hessian bands measuring 48 cm treated with 0.06 g, 0.10 g and 0.15 g of transfluthrin were tested in large cage semi-field and full field experiments. Sandals affixed with hessian bands measuring 240 cm and treated with 0.10 g and 0.15 g of transfluthrin were also tested semi field experiments. Human landing catches (HLC) were used to assess reduction in biting exposure by comparing proportions of mosquitoes landing on volunteers wearing treated and untreated sandals. Sandals were tested against insectary reared Anopheles arabiensis mosquitoes in semi-field experiments and against wild mosquito species in rural Tanzania.

RESULTS

In semi-field tests, sandals fitted with hessian bands measuring 48 cm and treated with 0.15 g, 0.10 g and 0.06 g transfluthrin reduced mosquito landings by 45.9%, (95% confidence interval (C.I.) 28-59%), 61.1% (48-71%), and 25.9% (9-40%), respectively compared to untreated sandals. Sandals fitted with hessian bands measuring 240 cm and treated with 0.15 g and 0.10 g transfluthrin reduced mosquito landings by 59% (43-71%) and 64% (48-74%), respectively. In field experiments, sandals fitted with hessian bands measuring 48 cm and treated with 0.15 g transfluthrin reduced mosquito landings by 70% (60-76%) against Anopheles gambiae sensu lato, and 66.0% (59-71%) against all mosquito species combined.

CONCLUSION

Transfluthrin-treated sandals conferred significant protection against mosquito bites in semi-field and field settings. Further evaluation is recommended for this tool as a potential complementary intervention against malaria. This intervention could be particularly useful for protecting against outdoor exposure to mosquito bites. Additional studies are necessary to optimize treatment techniques and substrates, establish safety profiles and determine epidemiological impact in different settings.

背景

如果要实现消除疟疾，就需要解决户外和傍晚蚊虫叮咬的问题。虽然室内靶向干预措施，如经杀虫剂处理的蚊帐和室内滞留喷洒，仍然是必不可少的，但迫切需要采取补充措施来解决持续的户外传播问题，以最大限度地提高效果。主要的疟疾传播媒介主要在人类宿主的脚和脚踝周围叮咬。因此，本研究调查了用有效空间驱避剂处理的凉鞋是否可以防止户外蚊虫叮咬。

方法

在大型笼式半野外和野外试验中，对用 0.06、0.10 和 0.15 克的呋虫胺处理的 48 厘米长的麻布条固定的凉鞋进行了测试。还用 0.10 和 0.15 克呋虫胺处理的 240 厘米长的麻布条固定的凉鞋也在半野外试验中进行了测试。人类着陆捕捉（HLC）用于通过比较志愿者穿着处理过和未处理过的凉鞋时蚊子着陆的比例来评估叮咬暴露的减少。在半野外试验中，用昆虫饲养的埃及伊蚊对凉鞋进行了测试，在坦桑尼亚农村对野生蚊种进行了测试。

结果

在半野外试验中，用 0.15、0.10 和 0.06 克呋虫胺处理的 48 厘米长麻布条固定的凉鞋分别减少了 45.9%（28-59%）、61.1%（48-71%）和 25.9%（9-40%）的蚊子着陆。用 0.15 和 0.10 克呋虫胺处理的 240 厘米长麻布条固定的凉鞋分别减少了 59%（43-71%）和 64%（48-74%）的蚊子着陆。在野外试验中，用 0.15 克呋虫胺处理的 48 厘米长麻布条固定的凉鞋对冈比亚按蚊亚种的蚊子着陆减少了 70%（60-76%），对所有蚊子种类的综合减少了 66.0%（59-71%）。