泰国乌汶府伊蚊属按蚊组内的物种多样性和抗药性。

Species diversity and insecticide resistance within the Anopheles hyrcanus group in Ubon Ratchathani Province, Thailand.

机构信息

Department of Entomology, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom, Thailand.

Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Institut de Recherche pour le Développement (IRD), University of Montpellier, Montpellier, France.

出版信息

Parasit Vectors. 2020 Oct 17;13(1):525. doi: 10.1186/s13071-020-04389-4.

DOI:10.1186/s13071-020-04389-4

PMID:33069255

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7568835/

Abstract

BACKGROUND

Members of the Anopheles hyrcanus group have been incriminated as important malaria vectors. This study aims to identify the species and explore the insecticide susceptibility profile within the Anopheles hyrcanus group in Ubon Ratchathani Province, northeastern Thailand where increasing numbers of malaria cases were reported in 2014.

METHODS

Between 2013 and 2015, five rounds of mosquito collections were conducted using human landing and cattle bait techniques during both the rainy and dry seasons. Anopheles mosquitoes were morphologically identified and their insecticide susceptibility status was investigated. Synergist bioassays were carried out with An. hyrcanus (s.l.) due to their resistance to all insecticides. An ITS2-PCR assay was conducted to identify to species the Hyrcanus group specimens.

RESULTS

Out of 10,361 Anopheles females collected, representing 18 taxa in 2 subgenera, 71.8% were morphologically identified as belonging to the Hyrcanus Group (subgenus Anopheles), followed by An. barbirostris group (7.9%), An. nivipes (6.5%), An. philippinensis (5.9%) and the other 14 Anopheles species. Specimens of the Hyrcanus Group were more prevalent during the rainy season and were found to be highly zoophilic. Anopheles hyrcanus (s.l.) was active throughout the night, with an early peak of activity between 18:00 h and 21:00 h. ITS2-PCR assay conducted on 603 DNA samples from specimens within the Hyrcanus Group showed the presence of five sisters species. Anopheles peditaeniatus was the most abundant species (90.5%, n = 546), followed by An. nitidus (4.5%, n = 27), An. nigerrimus (4.3%, n = 26), An. argyropus (0.5%, n = 3), and An. sinensis (0.2%, n = 1). All An. hyrcanus (s.l.) specimens that were found resistant to insecticides (deltamethrin 0.05%, permethrin 0.75% and DDT 4% and synergist tests) belonged to An. peditaeniatus. The degree of resistance in An. peditaeniatus to each of these three insecticides was approximately 50%. Addition of PBO (Piperonyl butoxide), but not DEF (S.S.S-tributyl phosphotritioate), seemed to restore susceptibility, indicating a potential role of oxidases as a detoxifying enzyme resistance mechanism.

CONCLUSIONS

A better understanding of mosquito diversity related to host preference, biting activity and insecticide resistance status will facilitate the implementation of locally adapted vector control strategies.

摘要

背景

已证实按蚊属（Anopheles）中的某些种类是重要的疟疾传播媒介。本研究旨在确定乌汶府（Ubon Ratchathani Province）按蚊属（Anopheles）组内的物种，并研究其对杀虫剂的敏感性，因为 2014 年该地区报告了越来越多的疟疾病例。

方法

2013 年至 2015 年，我们在雨季和旱季期间，使用人诱捕和牛诱捕技术进行了五轮蚊子采集。对按蚊进行形态学鉴定，并对其杀虫剂敏感性进行了研究。由于对所有杀虫剂均有抗性，因此对按蚊（s.l.）进行了增效剂生物测定。对 Hyrcanus 组标本进行 ITS2-PCR 检测以确定物种。

结果

共采集了 10361 只雌性按蚊，代表 2 个亚属的 18 个分类群，其中 71.8%被鉴定为属于 Hyrcanus 组（按蚊亚属），其次是巴比亚罗氏属（An. barbirostris）组（7.9%）、喜山库蚊（An. nivipes）（6.5%）、菲律宾按蚊（An. philippinensis）（5.9%）和其他 14 种按蚊。Hyrcanus 组的标本在雨季更为普遍，并且具有很强的嗜血性。按蚊（s.l.）整个晚上都很活跃，活动高峰出现在 18:00 至 21:00 之间。对 Hyrcanus 组 603 个 DNA 样本进行的 ITS2-PCR 检测显示存在 5 种姐妹种。按蚊（An. peditaeniatus）最为丰富（90.5%，n=546），其次是按蚊（An. nitidus）（4.5%，n=27）、按蚊（An. nigerrimus）（4.3%，n=26）、按蚊（An. argyropus）（0.5%，n=3）和中华按蚊（An. sinensis）（0.2%，n=1）。发现所有对杀虫剂（溴氰菊酯 0.05%、氯菊酯 0.75%和滴滴涕 4%以及增效剂试验）具有抗性的 Hyrcanus 组（s.l.）标本均属于按蚊（An. peditaeniatus）。按蚊（An. peditaeniatus）对这三种杀虫剂的抗性程度约为 50%。添加 PBO（胡椒基丁醚）而非 DEF（S.S.S-三丁基磷酸酯）似乎恢复了敏感性，表明氧化酶可能作为一种解毒酶抗性机制发挥作用。