Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Mar 31:14:137.
doi: 10.1186/s12936-015-0662-y.

Knockdown resistance of Anopheles sinensis in Henan province, China

Affiliations

Knockdown resistance of Anopheles sinensis in Henan province, China

Hong-wei Zhang et al. Malar J. .

Abstract

Background: Vivax malaria was historically epidemic in Henan Province of China and Anopheles sinensis was the main vectors and poor farming communities bare the greatest burden of disease. Knockdown resistance in An. sinensis is one of the mechanisms of resistance against pyrethroids. In the present study, the frequency of mutations from An. sinensis was examined in Henan province, China.

Methods: Anopheles was collected from Kaifeng, Tongbai, Tanghe, Pingqiao, Shihe, and Yongcheng counties of Henan province in 2013. Molecular identification of Anopheles species was conducted by polymerase chain reaction (PCR) amplifying the internal transcribed spacer 2 (ITS2). Part of the IIS6 domain of the para-type sodium channel protein gene was polymerase chain reaction-amplified and directly sequenced. Frequency and geographic difference of kdr gene mutant types were analysed.

Results: 208 Anopheles were received molecular identification, of which 169 (81.25%) were An. sinensis, 25 (12.02%) were Anopheles yatsushiroensis, and 12 (5.77%) were Anopheles lesteri. A 325 bp fragment of the para-type sodium channel gene including position 1014 was successfully sequenced from 139 Anopheles, of which 125 (89.93%) were An. sinensis, 12 (8.63%) were An. yatsushiroensis, 2 (1.44%) were An. lesteri. The molecular analyses revealed that mutations existed at codon 1014 in An. sinensis but not in An. yatsushiroensis and An. lesteri. Frequency of kdr mutation was 73.60% (92/125) from population of An. sinensis in Henan province, of which L1014F (TTT + TTC) allele frequencies accounted for 46.40% (58/125), and was higher than that of L1014C(TGT) which accounted for 27.20% (34/125) ( χ2 = 55.423, P < 0.001). The frequency of kdr mutation in Kaifeng county was 100% (49/49), and was higher than that of 37.93% (11/29) in Tongbai, 54.55% (6/11) in Pingqiao, 50.00% (3/3) in Shihe, and 62.50% (10/16) in Yongcheng county, respectively (χ2 = 39.538, P < 0.001; χ2 = 24.298, P < 0.001; χ2 = 25.913, P < 0.001; χ2 = 20.244, P < 0.001). While 92.86% (13/14) frequency of kdr mutation was found in Tanghe county, which was higher than that in Tongbai county (χ2 = 11.550, P = 0.0018).

Conclusions: A high frequency of kdr gene mutations from population of An. sinensis in Henan province was found.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Examples of nucleotide sequence chromatograms of kdr genotypes detected in Anopheles sinensis from Henan province. The position at codon 1014 of the para-type sodium channel gene is indicated by a rectangle box. A: three types of homozygote genotypes detected; and B: four types of heterozygote genotypes detected (K = G/T; Y = T/C; S = G/C).

References

    1. Oh SS, Hur MJ, Joo GS, Kim ST, Go JM, Kim YH, et al. Malaria vector surveillance in Ganghwa-do, a malaria-endemic area in the Republic of Korea. Korean J Parasitol. 2010;48:35–41. doi: 10.3347/kjp.2010.48.1.35. - DOI - PMC - PubMed
    1. Manh CD, Beebe NW, Van VN, Quang TL, Lein CT, Nguyen DV, et al. Vectors and malaria transmission in deforested, rural communities in north-central Vietnam. Malar J. 2010;9:259. doi: 10.1186/1475-2875-9-259. - DOI - PMC - PubMed
    1. Paredes-Esquivel C, Harbach RE, Townson H. Molecular taxonomy of members of the Anopheles hyrcanus group from Thailand and Indonesia. Med Vet Entomol. 2011;25:348–52. doi: 10.1111/j.1365-2915.2010.00937.x. - DOI - PubMed
    1. Hii J, Rueda LM. Malaria vectors in the Greater Mekong Subregion: overview of malaria vectors and remaining challenges. Southeast Asian J Trop Med Public Health. 2013;44(Suppl 1):73–165. - PubMed
    1. WHO . WHO guidance for countries on combining indoor residual spraying and long-lasting insecticidal nets. Geneva: World Health Organization; 2014.

Publication types