Evidence map›Paper›PMID 41593697›Full record

ArticleMalaria journal2026

Urban evolution of insecticide resistance and susceptibility patterns of Anopheles coluzzii in Southeastern Nigeria: implications for malaria vector control.

Amarachi Keziah Ezeike, Simon Pierre Yinyang Danga, Valentine Chukwuma Ezenwa, Chinaza Favour Chukas, Emmanuel Ogbonnia Ogudu, Chukwuebuka Michael Nwosu, Ijeoma Ngozi Ebenebe, Chidimma Ruth Chukwunwejim, Angus Nnamdi Oli, Charles Okechukwu Esimone

Abstract read
In one paragraph

Article in Malaria journal, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
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1 · What the graph read from it

What it found

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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

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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

1 citing paper in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Amarachi Keziah EzeikeDepartment of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Anambra, Nigeria.
Simon Pierre Yinyang DangaDepartment of Biological Sciences, Faculty of Science, University of Garoua, Garoua, Cameroon. dangayisipi@yahoo.fr.
Valentine Chukwuma EzenwaIntegrity Research Laboratory, Oko, Anambra, Nigeria.
Chinaza Favour ChukasIntegrity Research Laboratory, Oko, Anambra, Nigeria.
Emmanuel Ogbonnia OguduFederal Ministry of Health, National Arbovirus and Vectors Research Centre Enugu, Enugu, Nigeria.
Chukwuebuka Michael NwosuFederal Ministry of Health, National Arbovirus and Vectors Research Centre Enugu, Enugu, Nigeria.
Ijeoma Ngozi EbenebeDepartment of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Anambra, Nigeria.
Chidimma Ruth ChukwunwejimDepartment of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Anambra, Nigeria.
Angus Nnamdi OliDepartment of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Anambra, Nigeria.
Charles Okechukwu EsimoneDepartment of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Anambra, Nigeria.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundInsecticide resistance among malaria vectors remains a critical obstacle to effective vector control and malaria elimination across sub-Saharan Africa. This study assessed the phenotypic and genotypic resistance profiles of Anopheles coluzzii populations in three urban centres of Anambra State, Southeastern Nigeria: Awka, Onitsha and Nnewi.

methodsLarvae were collected from Awka, Onitsha and Nnewi and reared to adults for WHO insecticide susceptibility tests. Species identification, molecular form determination (PCR-RFLP using HhaI enzyme) and screening for kdr L1014F and ace-1 G119S mutations were performed.

resultsMolecular diagnostics confirmed that all specimens were An. coluzzii. Mortality to deltamethrin was low across all sites (Awka: 63%, Onitsha: 61% and Nnewi: 45%), indicating resistance. DDT also showed markedly reduced susceptibility (Awka: 56%, Onitsha: 25% and Nnewi: 20%), consistent with resistance. In contrast, full susceptibility was observed to bendiocarb (100%) and pirimiphos-methyl (100%) in all locations. The kdr 1014F allele occurred at high frequencies across all locations (Awka: 0.72, Onitsha: 0.77 and Nnewi: 0.81), predominantly represented by RR and RS genotypes. In contrast, the ace-1 G119S allele was present at very low frequencies (Awka: 0.07, Onitsha: 0.10 and Nnewi: 0.12), with most mosquitoes carrying the susceptible SS genotype.

conclusionsUrban An. coluzzii populations in southeastern Nigeria exhibit operationally significant resistance to pyrethroids and DDT, driven largely by high kdr allele frequencies, while remaining susceptible to carbamates and organophosphates. These patterns highlight the need for continued resistance surveillance and tailored insecticide-based interventions.

Indexed as

AnophelesInsecticide ResistanceInsecticidesMosquito VectorsAnimalsFemaleGenotypeLarvaMalariaMosquito ControlNigeriaPyrethrinsInsecticidesPyrethrinsAce-1 geneAnambra StateAnopheles coluzziiInsecticide resistanceKnockdown resistance (kdr)Molecular diagnosticsUrban malaria vectorsVector control

Identifiers

PMID41593697
PMCPMC12879429

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LicenceCC BY-NC-ND
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Registered trials

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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.