De Ang Joshua Xin, Yaman Khatijah, Kadir Khamisah Abdul, Matusop Asmad, Singh Balbir
Malaria Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak, Kuching, Sarawak, Malaysia.
Sarawak Department of Health, Kuching, Sarawak, Malaysia.
Sci Rep. 2021 Apr 8;11(1):7739. doi: 10.1038/s41598-021-86107-3.
Plasmodium knowlesi is the main cause of malaria in Sarawak, where studies on vectors of P. knowlesi have been conducted in only two districts. Anopheles balabacensis and An. donaldi were incriminated as vectors in Lawas and An. latens in Kapit. We studied a third location in Sarawak, Betong, where of 2169 mosquitoes collected over 36 days using human-landing catches, 169 (7.8%) were Anopheles spp. PCR and phylogenetic analyses identified P. knowlesi and/or P. cynomolgi, P. fieldi, P. inui, P. coatneyi and possibly novel Plasmodium spp. in salivary glands of An. latens and An. introlatus from the Leucosphyrus Group and in An. collessi and An. roperi from the Umbrosus Group. Phylogenetic analyses of cytochrome oxidase subunit I sequences indicated three P. knowlesi-positive An. introlatus had been misidentified morphologically as An. latens, while An. collessi and An. roperi could not be delineated using the region sequenced. Almost all vectors from the Leucosphyrus Group were biting after 1800 h but those belonging to the Umbrosus Group were also biting between 0700 and 1100 h. Our study incriminated new vectors of knowlesi malaria in Sarawak and underscores the importance of including entomological studies during the daytime to obtain a comprehensive understanding of the transmission dynamics of malaria.
诺氏疟原虫是砂拉越疟疾的主要病因，此前仅在两个地区开展过关于诺氏疟原虫传播媒介的研究。在拉瓦斯地区，巴拉望按蚊和多氏按蚊被认定为传播媒介，而在加帛地区，迟暮按蚊被认定为传播媒介。我们对砂拉越的第三个地点——美里进行了研究，在36天内通过人饵诱捕法共捕获2169只蚊子，其中169只（7.8%）为按蚊属。聚合酶链反应（PCR）和系统发育分析在来自 leucosphyrus 组的迟暮按蚊和内罗按蚊以及来自 umbrosus 组的柯氏按蚊和罗氏按蚊的唾液腺中鉴定出了诺氏疟原虫和/或食蟹猴疟原虫、费氏疟原虫、伊氏疟原虫、科氏疟原虫以及可能的新型疟原虫物种。细胞色素氧化酶亚基I序列的系统发育分析表明，三只检测出诺氏疟原虫阳性的内罗按蚊在形态上被误鉴定为迟暮按蚊，而柯氏按蚊和罗氏按蚊无法通过所测区域进行区分。几乎所有来自 leucosphyrus 组的传播媒介在18:00之后才叮咬，但属于 umbrosus 组的传播媒介在07:00至11:00之间也会叮咬。我们的研究确定了砂拉越诺氏疟疾病的新传播媒介，并强调了纳入白天的昆虫学研究以全面了解疟疾传播动态的重要性。
