This site needs JavaScript to work properly. Please enable it to take advantage of the complete set of features!
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.

NIH NLM Logo
Log in
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Mar 16;14(3):e0007753.
doi: 10.1371/journal.pntd.0007753. eCollection 2020 Mar.

Loss of pyrethroid resistance in newly established laboratory colonies of Aedes aegypti

Affiliations

Loss of pyrethroid resistance in newly established laboratory colonies of Aedes aegypti

Farah Z Vera-Maloof et al. PLoS Negl Trop Dis. .

Abstract

Background: Resistance to pyrethroid insecticides in Aedes aegypti has become widespread after almost two decades of the frequent use of these pesticides to reduce arbovirus transmission. Despite this resistance, pyrethroids continue to be used because they are relatively inexpensive and have low human toxicity. Resistance management has been proposed as a way to retain the use of pyrethroids in natural populations. A key component of resistance management is the assumption that negative fitness is associated with resistance alleles such that resistance alleles will decline in frequency when the insecticides are removed. At least three studies in Ae. aegypti have demonstrated a decrease in pyrethroid resistance once the insecticide has been removed.

Methods/principal findings: The present study aims to evaluate variation in the loss of pyrethroid resistance among newly established laboratory populations of Ae. aegypti from Mexico. Eight field collections were maintained for up to eight generations, and we recorded changes in the frequencies of the mutations at the V1,016I locus and at the F1,534C locus in the voltage-gated sodium channel gene (VGSC). I1,016 and C1,534 confer resistance. We also examined resistance ratios (RR) with type 1 and 2 pyrethroids.

Conclusions/significance: We demonstrate that, in general, the frequency of the Ae. aegypti pyrethroid-resistance alleles I1,016 and C1,534 decline when they are freed from pyrethroid pressure in the laboratory. However, the pattern of decline is strain dependent. In agreement with earlier studies, the RR was positively correlated with the frequencies of the resistance allele I1,016 and showed significant protection against permethrin, and deltamethrin, whereas F1,534C showed protection against permethrin but not against deltamethrin.

PubMed Disclaimer

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1
A) Resistance to permethrin in generations F3, F6 and F8 in absence of insecticides. Resistance ratios were calculated by dividing the LC50 of our sites by the LC50 determined for New Orleans. B) Resistance to deltamethrin in generations F3, F6 and F8 in absence of insecticides. Resistance ratios were calculated by dividing the LC50 of our sites by the LC50 determined for New Orleans.
Fig 2
Fig 2
A) Frequency of the resistant allele I1,016 in all three replicates in the eight different collections over eight generations. Asterisks indicate a statistical difference among the replicates. B) Mean frequency of the resistant allele I1,016 among all three replicates and the 95% high-density intervals (HDI 95%). Pearson correlation coefficient between I1,016 frequencies and generation number and the associated significance appear at the bottom of each graph.
Fig 3
Fig 3
A) Frequency of the resistant allele C1,534 in all three replicates in the eight different collections over eight generations. An asterisk indicates statistical differences among the three replicates. B) Mean frequency of the resistant allele C1,534 among all three replicates and the 95% high-density intervals (HDI 95%). The Pearson correlation coefficient between the C1,534 frequencies and generation number and the associated significance appear at the bottom of each graph.
Fig 4
Fig 4. Frequency of genotypes at locus V1,016I over eight generations in the absence of pyrethroids.
A) Susceptible-homozygote = VV1,016, B) Heterozygote = VI1,016, and C) Resistant-homozygote = II1,016.
Fig 5
Fig 5. Frequencies of genotypes at locus F1,534C over eight generations in the absence of insecticides.
Susceptible-homozygote = FF1,534, heterozygote = FC1,534, and resistant-homozygote = CC1,534.
Fig 6
Fig 6. Frequency of the four potential di-locus haplotypes between loci V1,016I and F1,534C over eight generations in the absence of insecticides.
Haplotypes: both susceptible alleles in cis = V1,016/F1,534, susceptible V1,016 and resistant C1,534 alleles in cis = V1,016/C1,534, resistant I1,016 and susceptible F1,534 alleles in cis = I1,016/F1,534, and resistant I1,016 and resistant C1,534 alleles in cis = I1,016/C1,534.
Fig 7
Fig 7. Frequency of the nine di-locus haplotypes over eight generations in the absence of insecticides.
Fig 8
Fig 8
Correlation between the resistant alleles: I1,016 and C1,534 and the pyrethroid resistance ratio calculated for A) permethrin and B) deltamethrin.

References

    1. Macoris MD, Martins AJ, Andrighetti MTM, Lima JBP, Valle D. Pyrethroid resistance persists after ten years without usage against Aedes aegypti in governmental campaigns: Lessons from Sao Paulo State, Brazil. PLoS Negl Trop Dis. 2018;12(3). ARTN e0006390 10.1371/journal.pntd.0006390. WOS:000431268900085. - PMC - PubMed
    1. Amelia-Yap ZH, Chen CD, Sofian-Azirun M, Low VL. Pyrethroid resistance in the dengue vector Aedes aegypti in Southeast Asia: present situation and prospects for management. Parasit Vectors. 2018;11. ARTN 332 10.1186/s13071-018-2899-0. WOS:000434235600001. - PMC - PubMed
    1. Chang C, Huang XY, Chang PC, Wu HH, Dai SM. Inheritance and stability of sodium channel mutations associated with permethrin knockdown resistance in Aedes aegypti. Pestic Biochem and Physiol. 2012;104(2):136–42. 10.1016/j.pestbp.201206003 WOS:000311068900010. - DOI
    1. Brito LP, Linss JGB, Lima-Camara TN, Belinato TA, Peixoto AA, Lima JBP, et al. Assessing the effects of Aedes aegypti kdr mutations on pyrethroid resistance and its fitness cost. PLoS One. 2013;8(4). ARTN e60878 10.1371/journal.pone.0060878. WOS:000317898000080. - PMC - PubMed
    1. Grossman MK, Uc-Puc V, Rodriguez J, Cutler DJ, Morran LT, Manrique-Saide P, et al. Restoration of pyrethroid susceptibility in a highly resistant Aedes aegypti population. Biol Lett. 2018;14(6). ARTN 20180022 10.1098/rsbl.2018.0022. WOS:000437005700002. - PMC - PubMed

Publication types

Full text links
Public Library of Science full text link Public Library of Science Free PMC article
Cite

AltStyle によって変換されたページ (->オリジナル) /