Faculty of Infectious and Tropical Diseases, Disease Control Department, London School of Hygiene and Tropical Medicine, WC1E 7HT, London, UK.
Medical Research Council (MRC) International Statistics and Epidemiology Epidemiology Group, London School of Hygiene and Tropical Medicine, WC1E 7HT, London, UK.
BMC Infect Dis. 2021 Feb 19;21(1):194. doi: 10.1186/s12879-021-05879-1.
Long-lasting insecticidal nets (LLINs) are currently the primary method of malaria control in sub-Saharan Africa and have contributed to a significant reduction in malaria burden over the past 15 years. However, this progress is threatened by the wide-scale selection of insecticide-resistant malaria vectors. It is, therefore, important to accelerate the generation of evidence for new classes of LLINs.
This protocol presents a three-arm superiority, single-blinded, cluster randomized controlled trial to evaluate the impact of 2 novel dual-active ingredient LLINs on epidemiological and entomological outcomes in Benin, a malaria-endemic area with highly pyrethroid-resistant vector populations. The study arms consist of (i) Royal Guard® LLIN, a net combining a pyrethroid (alpha-cypermethrin) plus an insect growth regulator (pyriproxyfen), which in the adult female is known to disrupt reproduction and egg fertility; (ii) Interceptor G2® LLIN, a net incorporating two adulticides (alpha-cypermethrin and chlorfenapyr) with different modes of action; and (iii) the control arm, Interceptor® LLIN, a pyrethroid (alpha-cypermethrin) only LLIN. In all arms, one net for every 2 people will be distributed to each household. Sixty clusters were identified and randomised 1:1:1 to each study arm. The primary outcome is malaria case incidence measured over 24 months through active case detection in a cohort of 25 children aged 6 months to 10 years, randomly selected from each cluster. Secondary outcomes include 1) malaria infection prevalence (all ages) and prevalence of moderate to severe anaemia in children under 5 years old, measured at 6 and 18 months post-intervention; 2) entomological indices measured every 3 months using human landing catches over 24 months. Insecticide resistance intensity will also be monitored over the study period.
This study is the second cluster randomised controlled trial to evaluate the efficacy of these next-generation LLINs to control malaria transmitted by insecticide-resistant mosquitoes. The results of this study will form part of the WHO evidence-based review to support potential public health recommendations of these nets and shape malaria control strategies of sub-Saharan Africa for the next decade.
ClinicalTrials.gov, NCT03931473 , registered on 30 April 2019.
长效杀虫蚊帐（LLINs）是目前撒哈拉以南非洲地区控制疟疾的主要方法，在过去 15 年中，它在降低疟疾负担方面发挥了重要作用。然而，这一进展受到杀虫剂耐药性疟疾病媒广泛选择的威胁。因此，加速生成新类别 LLINs 的证据非常重要。
本方案介绍了一项三臂优效性、单盲、整群随机对照试验，旨在评估 2 种新型双活性成分 LLINs 对贝宁（疟疾流行区，具有高度拟除虫菊酯抗性的蚊媒种群）的流行病学和昆虫学结局的影响。研究组包括：（i）皇家卫士®蚊帐，一种结合了拟除虫菊酯（α-氯氰菊酯）和昆虫生长调节剂（吡丙醚）的蚊帐，已知在成年雌性中会破坏繁殖和卵的生育能力；（ii）Interceptor G2®蚊帐，一种含有两种杀成虫剂（α-氯氰菊酯和氯氟吡氧乙酸）的蚊帐，具有不同的作用模式；（iii）对照组，Interceptor®蚊帐，一种仅含有拟除虫菊酯（α-氯氰菊酯）的蚊帐。在所有组中，每个家庭将分配到每两个人一个蚊帐。从每个群组中随机抽取 25 名年龄在 6 个月至 10 岁的儿童，组成一个队列，通过主动病例检测来测量 24 个月的疟疾发病情况，作为主要结局。次要结局包括：1）在干预后 6 个月和 18 个月，测量所有年龄的疟疾感染率（所有年龄）和 5 岁以下儿童中中度至重度贫血的患病率；2）使用人类降落捕捉法，每 3 个月测量一次，持续 24 个月的昆虫学指数。在研究期间还将监测杀虫剂抗性强度。
本研究是第二项评估下一代 LLINs 控制抗杀虫剂蚊虫传播疟疾的功效的整群随机对照试验。该研究的结果将作为世界卫生组织循证审查的一部分，以支持对这些蚊帐的潜在公共卫生建议，并为撒哈拉以南非洲地区未来十年的疟疾控制策略提供参考。
ClinicalTrials.gov，NCT03931473 ，于 2019 年 4 月 30 日注册。
