Evidence map›Paper›PMID 42141496›Full record

ArticleInfectious diseases of poverty2026

Signature of resistance gene evolution and pyrethroid resistance escalation in the major malaria vector Anopheles funestus across Kenyan malaria-endemic regions separated by the Rift Valley.

David P Tchouassi, Amine M Mustapha, Gilbert Rotich, Trizah K Milugo, Brenda Musimbi, Ambrose Oruni, Carlos S D Tagne, Luna Kamau, Mahamat Gadji, Magellan Tchouakui and 2 more

Abstract read
In one paragraph

Article in Infectious diseases of poverty, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

David P TchouassiInternational Centre of Insect Physiology and Ecology, PO Box 30772-00100, Nairobi, Kenya. dtchouassi@icipe.org.
Amine M MustaphaInternational Centre of Insect Physiology and Ecology, PO Box 30772-00100, Nairobi, Kenya.
Gilbert RotichInternational Centre of Insect Physiology and Ecology, PO Box 30772-00100, Nairobi, Kenya.
Trizah K MilugoInternational Centre of Insect Physiology and Ecology, PO Box 30772-00100, Nairobi, Kenya.
Brenda MusimbiInternational Centre of Insect Physiology and Ecology, PO Box 30772-00100, Nairobi, Kenya.
Ambrose OruniCentre for Research in Infectious Diseases, PO Box 13591, Yaoundé, Cameroon.
Carlos S D TagneCentre for Research in Infectious Diseases, PO Box 13591, Yaoundé, Cameroon.
Luna KamauCentre for Biotechnology Research and Development, Kenya Medical Research Institute, PO Box 54840-00200, Nairobi, Kenya.
Mahamat GadjiCentre for Research in Infectious Diseases, PO Box 13591, Yaoundé, Cameroon.
Magellan TchouakuiCentre for Research in Infectious Diseases, PO Box 13591, Yaoundé, Cameroon.
Baldwyn TortoInternational Centre of Insect Physiology and Ecology, PO Box 30772-00100, Nairobi, Kenya.
Charles S WondjiCentre for Research in Infectious Diseases, PO Box 13591, Yaoundé, Cameroon.

Funding

Wellcome Trust 222005/Z/20/Z
6 · The paper itself

Abstract

backgroundLandscape features such as the Rift Valley (RV) can restrict gene flow in malaria vectors and influence resistance patterns. Here, we assessed Plasmodium infection rates, resistance alleles and profiles in Anopheles funestus s.s. populations across Kenyan malaria-endemic regions separated by the RV.

methodsAnopheles funestus s.s. populations in western, coastal and Kerio Valley (KV, within the RV) were genotyped for key resistance markers using polymerase chain reaction (PCR). TaqMan assay combined with nested PCR were used to screen the samples for Plasmodium sporozoite infection and association with resistance alleles and genotype frequencies assessed using Fisher's exact test or Pearson's chi-square test. Following established WHO guidelines, phenotypic resistance using F1 progeny was also assessed using diagnostic, intensity and piperonyl butoxide (PBO)-synergistic assays.

resultsThe 4.3kb-SV (n = 336) and G454A-Cyp9k1 (n = 445) alleles were nearly fixed in western Kenya but declined towards the RV and coast, whereas L119F-GSTe2 (n = 392) increased across a west-KV-coast gradient with a novel haplotype distinct from known African variants detected at the coast. There were lower odds of Plasmodium infection in mosquitoes with L119F-GSTe2-RR than RS genotype (OR 0.2, P = 0.046). Likewise, mosquitoes harboring the R allele of the 4.3 kb marker had higher Plasmodium infection rates than the S allele (OR 5.7, P = 0.049). An. funestus populations exhibited a high degree of pyrethroid resistance with intensity higher in KV compared to western Kenya, a traditional malaria hotspot. Pre-exposure to PBO increased mortality for type II (deltamethrin, alpha-cypermethrin), than I (permethrin) pyrethroids, yet mortality remained lower in KV, suggesting non-P450-mediated resistance. An. funestus mosquitoes from the coast showed extreme permethrin resistance (< 10% mortality at 10 × dose). Resistance to dichlorodiphenyltrichloroethane was widespread, while all populations remained fully susceptible to bendiocarb, pirimiphos-methyl, clothianidin, and chlorfenapyr.

conclusionsRegion-specific selection may drive varying resistance profiles in An. funestus across Kenyan malaria-endemic regions separated by the Rift Valley, with implications for malaria transmission and insecticide resistance management.

Indexed as

AnophelesEvolution, MolecularInsecticide ResistanceInsecticidesMalariaMosquito VectorsPyrethrinsAnimalsGenotypeKenyaInsecticidesPyrethrinsAnopheles funestusGeographic barrierMalariaMetabolic resistancePyrethroid resistance escalationResistance markerRift ValleyTransmission

Identifiers

PMID42141496
PMCPMC13179624

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.