Historical survey of the kdr mutations in the populations of Anopheles sinensis in China in 1996–2014

Malaria Journal

Research

Hua Shi¹  Zhenzhou Yang¹  Jiannong Xu²  Wanqin Yu²  Yan Wang³  Yajun Ma³ 

[1] Center for Disease Control and Prevention of P. L.A., 100071, Beijing, China;Department of Biology, Molecular Biology Program, New Mexico State University, NM 88003, Las Cruces, USA;Department of Tropical Infectious Diseases, Second Military Medical University, 200433, Shanghai, China;

关键词: Anopheles sinensis;    Anopheles lesteri;    Pyrethroids;    Knockdown resistance;    Kdr;   

DOI  :  10.1186/s12936-015-0644-0

 received in 2014-10-26, accepted in 2015-03-07,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundAnopheles sinensis has become an important malaria vector in China. The long-term extensive utilization of pyrethroids for ITNs and IRS for mosquito control in the last three decades has resulted in the occurrence of resistant An. sinensis populations in many regions. Knockdown resistance (kdr), caused by point mutations in the VGSC gene, is one of the mechanisms that confer resistance to DDT and pyrethroids. Recently, several investigations revealed the kdr occurrence in some An. sinensis populations, however, no kdr data were available earlier than 2009. A survey tracking the dynamics of the kdr mutations in past decades would provide invaluable information to understand how the kdr alleles spread in mosquito populations temporally and spatially.MethodsA survey was conducted on the kdr alleles at condon 1014 of the VGSC gene and their distributions in 733 specimens of An. sinensis and 232 specimens of the other eight member species of the Anopheles hyrcanus group that were collected from 17 provinces in China in 1996–2014.ResultsA total of three kdr alleles, TTT (F), TTG (F) and TGT (C) were detected, and TGT (C) and TTT (F) were already present in the specimens from Jiangsu and Shandong as early as 1997. The TTT (F) was the most frequent mutant allele, and largely distributed in central China, namely Shandong, Jiangsu, Anhui, Henan, Shanghai, Jiangxi and Hubei. When data were analysed in three time intervals, 1996–2001, 2005–2009, 2010–2014, the prevalence of kdr alleles increased progressively over time in the populations in central China. In contrast, the kdr alleles were less frequent in the samples from other regions, especially in Yunnan and Hainan, despite the documented presence of pyrethroid resistant populations in those regions. Interestingly, no mutant alleles were detected in all 232 specimens of eight other species in the An. hyrcanus group.ConclusionThe survey revealed that the kdr occurrence and accumulation in the An. sinensis populations were more frequent in central China than in the other regions, suggesting that the kdr mutations may contribute significantly to the pyrethroid resistance in the mosquitoes in central China.

【 授权许可】

Unknown   
© Wang et al.; licensee BioMed Central. 2015. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.