背景:最近,细菌内共生体,包括Wolbachia和微孢子虫在内,被发现可以限制恶性疟原虫对按蚊的感染。这项研究旨在调查贝宁南部冈比亚按蚊和结肠按蚊中关键传播阻断内共生体的自然存在。
方法:本研究在七个公社进行(科托努,波尔图-诺沃,Aguégués,Ifangni,PobeAziémé,和大波波)贝宁南部。使用室内/室外人类着陆捕获物(HLC)和除虫菊喷雾捕获物(PSC)收集按蚊。经过形态学鉴定,使用PCR鉴定An。冈比亚sensulato(s.l.)达到物种水平,并筛选Wolbachia和微孢子虫的存在。还使用ELISA评估了恶性疟原虫子孢子感染。
结果:总体而言,An中的物种组成。冈比亚s.l.为53.7%。coluzzii,其余的是一个。冈比亚sensustricto(s.s.)。两种采样技术的综合数据显示,在An中,Wolbachia的平均感染率为5.1%(95%CI0.90-18.6)和1.3%(95%CI0.07-7.8)。冈比亚s.s.和An.coluzzii,分别。An微孢子虫的平均感染率为41.0%(95%CI25.9-57.8)。冈比亚s.s.和An的57.0%(95%CI45.4-67.9)。Coluzzii.Wolbachia只在Ifangni观察到,Pobe,还有科托努,而在所有研究社区中均检测到微孢子虫。HLC和PSC的汇总数据显示An的子孢子率(SR)为0.80%(95%CI0.09-2.87)和0.69%(95%CI0.09-2.87)。冈比亚和安.coluzzii,分别,平均值为0.74%(95%CI0.20-1.90)。在四只藏有恶性疟原虫的蚊子中,没有人也感染了Wolbachia,其中一个含有微孢子虫。
结论:本研究是实地收集的An自然感染的第一份报告。冈比亚s.l.来自贝宁的Wolbachia和微孢子虫种群。应持续努力,扩大蚊子中发现的细菌范围,具有开发基于内共生体的控制工具的潜力;此类干预措施可能会改变疟疾和虫媒病毒病传播的控制。
BACKGROUND: Recently, bacterial endosymbiont, including Wolbachia and Microsporidia were found to limit the infection of Anopheles mosquitoes with Plasmodium falciparum. This
study aimed to investigate the natural presence of key transmission-blocking endosymbionts in Anopheles gambiae and Anopheles coluzzii in Southern Benin.
METHODS: The present
study was conducted in seven communes (Cotonou, Porto-Novo, Aguégués, Ifangni, Pobè Athiémé, and Grand-Popo) of Southern Benin. Anopheles were collected using indoor/outdoor Human Landing Catches (HLCs) and Pyrethrum Spray Catches (PSCs). Following morphological identification, PCR was used to identify An. gambiae sensu lato (s.l.) to species level and to screen for the presence of both Wolbachia and Microsporidia. Plasmodium falciparum sporozoite infection was also assessed using ELISA.
RESULTS: Overall, species composition in An. gambiae s.l. was 53.7% An. coluzzii, while the remainder was An. gambiae sensu stricto (s.s.). Combined data of the two sampling techniques revealed a mean infection prevalence with Wolbachia of 5.1% (95% CI 0.90-18.6) and 1.3% (95% CI 0.07-7.8) in An. gambiae s.s. and An. coluzzii, respectively. The mean infection prevalence with Microsporidia was 41.0% (95% CI 25.9-57.8) for An. gambiae s.s. and 57.0% (95% CI 45.4-67.9) for An. coluzzii.
Wolbachia was only observed in Ifangni, Pobè, and Cotonou, while Microsporidia was detected in all
study communes. Aggregated data for HLCs and PSCs showed a sporozoite rate (SR) of 0.80% (95% CI 0.09-2.87) and 0.69% (95% CI 0.09-2.87) for An. gambiae and An. coluzzii, respectively, with a mean of 0.74% (95% CI 0.20-1.90). Of the four individual mosquitoes which harboured P. falciparum, none were also infected with Wolbachia and one contained Microsporidia.
CONCLUSIONS: The present
study is the first report of natural infections of field-collected An. gambiae s.l. populations from Benin with
Wolbachia and Microsporidia. Sustained efforts should be made to widen the spectrum of bacteria identified in mosquitoes, with the potential to develop endosymbiont-based control tools; such interventions could be the game-changer in the control of malaria and arboviral disease transmission.