Cited by 158Malaria Research and ControlInsect Resistance and GeneticsDengue and Mosquito Control Research

Spatial and temporal variation in the kdr allele L1014S in Anopheles gambiae s.s. and phenotypic variability in susceptibility to insecticides in Western Kenya

Open access
Mathias, Derrick K, Ochomo, Eric, Atieli, Francis, Ombok, Maurice, Nabie Bayoh, M, Olang, George, Muhia, Damaris, Kamau, Luna +5 more·2011·Malaria Journal

Abstract

Background: Malaria vector control in Africa depends upon effective insecticides in bed nets and indoor residual sprays. This study investigated the extent of insecticide resistance in Anopheles gambiae s.l., Anopheles gambiae s.s. and Anopheles arabiensis in western Kenya where ownership of insecticide-treated bed nets has risen steadily from the late 1990s to 2010. Temporal and spatial variation in the frequency of a knock down resistance (kdr) allele in A. gambiae s.s. was quantified, as was variation in phenotypic resistance among geographic populations of A. gambiae s.l. Methods: To investigate temporal variation in kdr frequency, individual specimens of A. gambiae s.s. from two sentinel sites were genotyped using RT-PCR from 1996-2010. Spatial variation in kdr frequency, species composition, and resistance status were investigated in additional populations of A. gambiae s.l. sampled in western Kenya in 2009 and 2010. Specimens were genotyped for kdr as above and identified to species via conventional PCR. Field-collected larvae were reared to adulthood and tested for insecticide resistance using WHO bioassays. Results: Anopheles gambiae s.s. showed a dramatic increase in kdr frequency from 1996 - 2010, coincident with the scale up of insecticide-treated nets. By 2009-2010, the kdr L1014S allele was nearly fixed in the A. gambiae s.s. population, but was absent in A. arabiensis. Near Lake Victoria, A. arabiensis was dominant in samples, while at sites north of the lake A. gambiae s.s was more common but declined relative to A. arabiensis from 2009 to 2010. Bioassays demonstrated that A. gambiae s.s. had moderate phenotypic levels of resistance to DDT, permethrin and deltamethrin while A. arabiensis was susceptible to all insecticides tested. Conclusions: The kdr L1014S allele has approached fixation in A. gambiae s.s. populations of western Kenya, and these same populations exhibit varying degrees of phenotypic resistance to DDT and pyrethroid insecticides. The near absence of A. gambiae s.s. from populations along the lakeshore and the apparent decline in other populations suggest that insecticide-treated nets remain effective against this mosquito despite the increase in kdr allele frequency. The persistence of A. arabiensis, despite little or no detectable insecticide resistance, is likely due to behavioural traits such as outdoor feeding and/or feeding on non-human hosts by which this species avoids interaction with insecticide-treated nets.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1186/1475-2875-10-10

Cites

56 of 56 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • ITN coverage for populations has been associated with development of strong insecticide selection pressure by pyrethroid and increase of kdr allele frequency.

    “According to Mathias et al. [32], ITN coverage for populations has been associated with a development of strong insecticide selection pressure by pyrethroid and increase of kdr allele frequency.”
  • Currently, the increasing use of insecticides for malaria vector control plays an important role in the insecticide selection pressure.

    “Currently, the increasing use of insecticides for malaria vector control plays an important role in the insecticide selection pressure.”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 3

  1. Roberts DR Andre RG Insecticide resistant issues in vectors Am J Trop Med Hyg 1994 50 Suppl 21 34 8024082
  2. Beach RF Ruebush TK Sexton JD Hightower A Roberts J Evaluation of permethrin-impregnated bed-nets and curtains during seasonal periods of intense malaria transmission in western Kenya Am J Trop Med Hyg 1993 49 230 300 8372952
  3. Kamau L Agai D Matoke D Wachira L Gikandi G Vulule JM Status of insecticide susceptibility in Anopheles gambiae sensu lato and Anopheles funestus mosquitoes from western Kenya J Insect Sci 2008 8 11 PMC3061582 20345290

Cited by

Sorted by citations

Authors
Mathias, D. K., Ochomo, E., Atieli, F., Ombok, M., Nabie Bayoh, M., Olang, G., Muhia, D., Kamau, L., Vulule, J. M., Hamel, M. J., Hawley, W. A., Walker, E. D., & Gimnig, J. E.
Affiliations
  • Kenya Medical Research Institute (KE)
  • Centers for Disease Control and Prevention (US)
  • Michigan State University (US)
Corresponding author
  • Walker, Edward D
  • Gimnig, John E
Venue
Malaria Journal
Published
2011-01-14
Volume
10
Issue
1
Pages
10-10
ISSN
1475-2875 (ISSN-L)
OpenAlex
W2106675599
Cited by
158
References
56
Citations by year
2026: 5 · 2025: 4 · 2024: 7 · 2023: 5 · 2022: 3 · 2021: 20 · 2020: 13 · 2019: 9 · 2018: 14 · 2017: 8 · 2016: 12 · 2015: 11 · 2014: 13 · 2013: 15 · 2012: 14
FWCI
14.78
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
  • Malaria Journal (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Kenyatta University Institutional Repository (Kenyatta University) (submittedVersion)
Funders
  • National Science Foundation (EF-072377)
  • Bill and Melinda Gates Foundation
  • Centers for Disease Control and Prevention
Topics
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Malaria Research and Control
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Insect Resistance and Genetics
  • Social Sciences › Sociology and Political Science › Dengue and Mosquito Control Research
Keywords
Anopheles arabiensis, knockdown resistance, insecticide resistance, pyrethroid resistance, DDT resistance, permethrin, deltamethrin, insecticide-treated nets, malaria vector control, species composition, spatiotemporal variation, Western Kenya
MeSH terms
Animals, Anopheles, Cattle, Child, Preschool, Drug Resistance, Female, Gene Frequency, Geography, Humans, Infant, Infant, Newborn, Insecticides, Kenya, Pregnancy, Time Factors, Insect Proteins, Amino Acid Substitution, Reverse Transcriptase Polymerase Chain Reaction

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review