背景:黄斑按蚊,小按蚊和按蚊是大湄公河次区域(GMS)疟疾传播的主要媒介。近年来,随着所有GMS国家朝着消除疟疾的方向前进,该地区的疟疾负担已大大减少。有必要调查按蚊的多样性和丰度状况,并评估疟原虫感染率,以了解这些媒介物种在GMS国家的疟疾传播潜力,以指导制定最新的媒介控制策略和干预措施。
方法:在上丁市对蚊子进行了调查,柬埔寨-老挝的Sainyabuli和Phongsaly省,泰国-老挝和中国-老挝边界,分别。通过在每个省的前哨地点过夜诱捕来收集蚊子。经过形态学鉴定,采用基于18SrRNA的巢式PCR检测捕获的按蚊中的疟疾寄生虫.
结果:共有18965只蚊子,包括2个亚属(按蚊亚属和Cellia亚属)和4个部落(TribesCulicini,Aedini,Armigerini和Mansoniini)被抓获。部落Culicini占捕获量的85.66%,其次是按蚊亚属(8.15%)。中华按蚊占按蚊亚属的99.81%。在按蚊的1683个个体或合并样本中,有25个发现了疟原虫感染。在25个阳性样本中,19,5和1是从Loum收集的,Pangkhom和SiemPang村,分别。八种按蚊被发现感染了疟原虫,即,A.sinensis,Kochi按蚊,迷走神经按蚊,A.minimus,环状按蚊,菲律宾按蚊,按蚊和An。dirus.恶性疟原虫的感染率,间日疟原虫和混合疟原虫寄生虫种类占0.12%(2/1683),1.31%(22/1683)和0.06%(1/1683),分别。
结论:总体而言,这项调查再次证实,大湄公河次区域国家的国际边境地区有多种按蚊携带疟原虫。中华按蚊在按蚊集合中占主导地位,并且是疟疾寄生虫的携带者,因此可能在疟疾传播中起重要作用。需要对疟疾病媒进行更广泛的调查,以揭示详细的病媒生物学,生态学,行为,以及GMS地区的遗传学,以协助规划和实施改进的疟疾控制策略。
BACKGROUND: Anopheles maculatus, Anopheles minimus and Anopheles dirus are the major vectors of malaria transmission in the Greater Mekong Subregion (GMS). The malaria burden in this region has decreased significantly in recent years as all GMS countries progress towards malaria elimination. It is necessary to investigate the Anopheles diversity and abundance status and assess the Plasmodium infection rates to understand the malaria transmission potential of these vector species in GMS countries to guide the development of up-to-date vector control strategies and interventions.
METHODS: A survey of mosquitoes was conducted in Stung Treng, Sainyabuli and Phongsaly Provinces on the Cambodia-Laos, Thailand-Laos and
China-Laos borders, respectively. Mosquito collection was done by overnight trapping at sentinel sites in each province. After morphological identification, the 18S rRNA-based nested-PCR was performed to detect malaria parasites in the captured Anopheles mosquitoes.
RESULTS: A total of 18 965 mosquitoes comprising of 35 species of 2 subgenera (Subgenus Anopheles and Subgenus Cellia) and 4 tribes (Tribes Culicini, Aedini, Armigerini and Mansoniini) were captured. Tribe Culicini accounted for 85.66% of captures, followed by Subgenus Anopheles (8.15%). Anopheles sinensis dominated the Subgenus Anopheles by 99.81%. Plasmodium-infection was found in 25 out of the 1 683 individual or pooled samples of Anopheles. Among the 25 positive samples, 19, 5 and 1 were collected from Loum, Pangkhom and Siem Pang village, respectively. Eight Anopheles species were found infected with Plasmodium, i.e., An. sinensis, Anopheles kochi, Anopheles vagus, An. minimus, Anopheles annularis, Anopheles philippinensis, Anopheles tessellatus and An. dirus. The infection rates of Plasmodium falciparum, Plasmodium vivax and mixture of Plasmodium parasite species were 0.12% (2/1 683), 1.31% (22/1 683) and 0.06% (1/1 683), respectively.
CONCLUSIONS: Overall, this survey re-confirmed that multiple Anopheles species carry malaria parasites in the international
border areas of the GMS countries. Anopheles sinensis dominated the Anopheles collections and as carriers of malaria parasites, therefore may play a significant role in malaria transmission. More extensive investigations of malaria vectors are required to reveal the detailed vector biology, ecology, behaviour, and genetics in GMS regions in order to assist with the planning and implementation of improved malaria control strategies.