Evidence map›Paper›PMID 41792771›Full record

ArticleMalaria journal2026

Longitudinal surveillance of Anopheles mosquitoes across different settings in Tanga and Unguja: increased distribution of An. merus in coastal and inland areas of Tanzania.

Neema B Kulaya, Lembris Laanyuni Njotto, Robert D Kaaya, Nancy A Kassam, Karin L Schiøler, Ottmar Cronie, Anna-Sofie Stensgaard, Wilfred Senyoni, Yahya A Derua, Filbert Francis and 11 more

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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
–field-weighted citation impact
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.

  1. Article
4 · The record

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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

21 authors.

Neema B KulayaKCMC University, Moshi, Tanzania. neema.kulaya@kcmcu.ac.tz.
Lembris Laanyuni NjottoCollege of Information and Communication Technology, University of Dar Es Salaam, (CoICT - UDSM), Dar Es Salaam, Tanzania.
Robert D KaayaKCMC University, Moshi, Tanzania.
Nancy A KassamKCMC University, Moshi, Tanzania.
Karin L SchiølerGlobal Health Section, Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
Ottmar CronieDepartment of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden. ottmar.cronie@gu.se.
Anna-Sofie StensgaardSection for Parasitology and Aquatic Pathobiology, Department for Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark.
Wilfred SenyoniCollege of Information and Communication Technology, University of Dar Es Salaam, (CoICT - UDSM), Dar Es Salaam, Tanzania.
Yahya A DeruaNational Institute for Medical Research, Amani Research Centre, Muheza, Tanzania.
Filbert FrancisNational Institute for Medical Research, Tanga Research Centre, Tanga, Tanzania.
John P A LusinguNational Institute for Medical Research, Tanga Research Centre, Tanga, Tanzania.
Bernard B MalongoNational Institute for Medical Research, Amani Research Centre, Muheza, Tanzania.
Ayubo KampangoSector de Estudos de Vectores, Instituto Nacional de Saúde (INS), Vila de Marracuene, Província de Maputo, Mozambique.
Mwinyi MsellemResearch Division, Ministry of Health, Zanzibar, United Republic of Tanzania.
Pascal MagnussenCentre for Translational Medicine and Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
Helle HanssonCentre for Translational Medicine and Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
Reginald A KavisheKCMC University, Moshi, Tanzania.
Christian W WangCentre for Translational Medicine and Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
Michael AlifrangisCentre for Translational Medicine and Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
Fatma Saleh *Department of Allied Health Sciences, School of Health and Medical Sciences, The State University of Zanzibar, Zanzibar, Tanzania.
Vito Baraka *National Institute for Medical Research, Tanga Research Centre, Tanga, Tanzania.

Funding

This study was supported by Danida Fellowship Centre (DFC) (https://dfcentre.com/) under The Ministry of Foreign Affairs of Denmark through the FFU project: Predicting vector-borne disease epidemics: Dissemination of risk forecasting using District Health Information Software2 in Tanzania (PreVBD) DFC file no. 19-02-KU).
6 · The paper itself

Abstract

backgroundEffective malaria vector control in endemic areas requires understanding the distribution and composition of Anopheles species, as shifts in malaria vector species and composition can influence the efficacy of control interventions and transmission patterns. The current study explored the temporal and spatial distribution of Anopheles species and their infection with Plasmodium in different transmission settings in Tanga region and Unguja, Zanzibar, United Republic of Tanzania.

methodsFrom September 2021 to December 2023, monthly entomological surveys were conducted in 11 villages in Tanga and four Shehias in Unguja. Anopheles mosquitoes were sampled every month in each of 11 villages in Tanga and four Shehias in Unguja, 10 households were consented to participate in each village or Shehia. Mosquitoes were collected indoors and outdoors using CDC light traps, Furvela tent traps, Indoor and Outdoor prokopack. Species identification was performed using PCR, and Plasmodium infections were detected using TaqMan real-time PCR assay.

resultsA total of 4771 Anopheles mosquitoes collected (3,766 and 905 in Tanga and Unguja respectively), PCR amplification failed in 100 samples. Among successfully identified specimens, An. gambiae s.s. (43.8%) and An. merus (37.1%) were predominant. In Unguja, An. arabiensis (55.7%) and An. merus (41.9%) were most common. Seasonal variations were observed, with An. gambiae s.s. and An. funestus s.s. peaking in the short rainy season, An. arabiensis peaking in both dry and long rainy seasons, and An. merus peaked during both the wet and dry seasons, suggesting relatively stable occurrence throughout the year. Plasmodium infection rates for An. gambiae s.s., An. funestus s.s., An. arabiensis, and An. merus were 3.0% in Tanga and 1.2% in Unguja but only found in An. arabiensis. In Tanga, An. gambiae s.s., An. merus, and An. funestus s.s. were more abundant in upland and lowland areas than in the highlands, with urbanization limiting An. merus occurrence. In Unguja, An. arabiensis and An. merus were less common in semi-urban areas but showed a sharp increase during the wet season.

conclusionsThe study indicates a shift in An. gambiae s.l. sibling species composition has taken place in the study areas compared to previous reports. In the past, An. merus was not considered an important vector in Tanzania. However, in this study An. merus was observed as the second most abundant species across coastal and inland areas of Tanga and Unguja during both wet and dry season. Combined with its observed infection with P. falciparum, the findings suggest An. merus may contribute to perennial transmission of malaria in the region. This presents a new challenge to malaria vector surveillance and control including the need for a year-round multi-strategic approach.

Indexed as

Animal DistributionAnophelesMosquito VectorsPlasmodiumAnimalsFemaleLongitudinal StudiesMalariaSeasonsTanzaniaAnopheles speciesMalariaPlasmodium speciesTanzaniaVector distribution

Identifiers

PMID41792771
PMCPMC13001284

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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.