Pretorius Elizabeth, Jones Robert T, Hutchins Harry, Teixeira Da Silva Eunice, Ceesay Sainey, Ndiath Mamadou Ousmane, d'Alessandro Umberto, Rodrigues Amabelia, Logan James G, Last Anna
Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK.
Arctech Innovation, Dagenham, London, UK.
Malar J. 2025 Jun 19;24(1):195. doi: 10.1186/s12936-025-05372-z.
The malaria-endemic Bijagós Archipelago is situated 50 km off the coast of mainland Guinea-Bissau. It is a seasonal malaria transmission setting, with insecticide-treated bed nets as its primary control strategy. Little is known about the vector diversity and behaviour across the Archipelago.
In 2019, a survey took place on 16 of the inhabited islands across the Archipelago. Adult mosquitoes were collected using odour-baited outdoor light traps and indoor light traps at houses selected at random. Larval surveys were conducted for each village sampled. Anopheles adults caught were morphologically identified and a sub-sample was analysed to identify species within the Anopheles gambiae complex using RFLP-PCR. Sporozoite positivity was detected within a sub-sample by CSP-ELISA.
Anopheles gambiae sensu lato was present on all islands sampled. Anopheles density varied between islands, with densities ranging from 0.0 to 98.7 per trapping night from indoor traps and 0.1-165.2 per trapping night from outdoor traps. Anopheles melas was the most commonly observed species, accounting for 85.2% of all Anopheles caught from both indoor and outdoor light traps. A high level of hybridization between An. gambiae sensu stricto and Anopheles coluzzii was seen on some islands across the Archipelago. The overall sporozoite rate was 0.86% (0.2% for indoor traps; 1.4% for outdoor traps).
Species within An. gambiae s.l. are the primary vectors on the Bijagós. Anopheles melas may contribute to transmission throughout the year in the Bijagós. The vector species composition, abundance and infection rates uncovered in this study are useful for informing tailored, effective vector control programme in the Bijagos.
疟疾流行的比热戈斯群岛位于几内亚比绍大陆海岸外50公里处。这是一个季节性疟疾传播地区，以使用杀虫剂处理过的蚊帐作为主要控制策略。关于该群岛的媒介多样性和行为知之甚少。
2019年，对该群岛16个有人居住的岛屿进行了一项调查。使用气味诱捕的户外灯光诱捕器和室内灯光诱捕器在随机选择的房屋中收集成年蚊子。对每个抽样村庄进行幼虫调查。对捕获的按蚊成虫进行形态学鉴定，并对一个子样本进行分析，以使用RFLP-PCR鉴定冈比亚按蚊复合体中的物种。通过CSP-ELISA在一个子样本中检测子孢子阳性。
在所有抽样岛屿上均发现了冈比亚按蚊复合组。不同岛屿的按蚊密度有所不同，室内诱捕器每诱捕夜的密度范围为0.0至98.7只，室外诱捕器每诱捕夜的密度范围为0.1至165.2只。梅氏按蚊是最常见的物种，占从室内和室外灯光诱捕器捕获的所有按蚊的85.2%。在该群岛的一些岛屿上，冈比亚按蚊指名亚种和科氏按蚊之间存在高度杂交。总体子孢子率为0.86%（室内诱捕器为0.2%；室外诱捕器为1.4%）。
冈比亚按蚊复合组中的物种是比热戈斯群岛的主要媒介。梅氏按蚊可能在比热戈斯群岛全年的传播中起作用。本研究中发现的媒介物种组成、丰度和感染率有助于为比热戈斯群岛制定量身定制且有效的媒介控制计划提供信息。
