Evidence map›Paper›PMID 41801979›Full record

ArticlePLoS neglected tropical diseases2026

Spatio-temporal analysis and geostatistical modelling of onchocerciasis prevalence in Nigeria to support elimination efforts.

Ayodele Samuel Babalola, Taiwo A Adekunle, Taiwo P Babatunde, Yasmeen A Adeniyi, Omolola Adeniran, Olaitan Omitola, Edore Edwin Ito, Abiodun Olakiigbe, Pam V Gyang, Emeka Makata and 6 more

Abstract read
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Article in PLoS neglected tropical diseases, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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4 · The record

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5 · Who and what money

Authors and funding

16 authors.

Ayodele Samuel BabalolaDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.ORCID https://orcid.org/0000-0003-0540-5675
Taiwo A AdekunleOsun State University, Osogbo, Nigeria.
Taiwo P BabatundeDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Yasmeen A AdeniyiMedical Statistics Programme, Department of Population Health Science, University of Leicester, Leicester, United Kingdom.
Omolola AdeniranNeglected Tropical Diseases Control Unit, Federal Ministry of Health, Abuja, Nigeria.
Olaitan OmitolaFederal University of Agriculture, Abeokuta, Nigeria.
Edore Edwin ItoDelta State University, Abraka, Nigeria.
Abiodun OlakiigbeDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Pam V GyangDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Emeka MakataNeglected Tropical Diseases Control Unit, Federal Ministry of Health, Abuja, Nigeria.
Babatunde AdewaleDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Olaoluwa P AkinwaleDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Olufunmilayo A IdowuFederal University of Agriculture, Abeokuta, Nigeria.
Olabanji A SurakatOsun State University, Osogbo, Nigeria.
Adedapo O AdeogunDepartment of Public Health and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Monsuru A AdelekeOsun State University, Osogbo, Nigeria.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Nigeria has made significant progress toward the elimination of onchocerciasis through mass drug administration (MDA) of ivermectin, with ten states recently declared eligible to stop treatment following WHO-recommended epidemiological and entomological assessments. However, reliable spatial prevalence estimates remain necessary to guide elimination strategies, particularly in areas with limited surveillance. We applied model-based geostatistical analysis using Monte Carlo Maximum Likelihood Estimation to assess the spatio-temporal distribution of onchocerciasis prevalence across Nigeria from 1989 to 2024. Climatic, hydrographic, socio-economic, and topographic variables were incorporated to predict prevalence in unsampled locations. Predicted prevalence declined substantially over time. During 1997-2000, 64.9% (24/37) of states had mean predicted prevalence between 10-30%, and 5.4% (2/37) exceeded 30%. By 2017-2020, 70.3% (26/37) of states were classified within the 0-2% category, increasing to 86.5% (32/37) in 2021-2024. Nevertheless, resurgence was observed in selected areas; for example, Taraba State showed an absolute increase of 44.1 percentage points between 2013-2016 and 2021-2024 (p = 0.013). High-prevalence clusters persisted along international and interstate borders, particularly in southern Nigeria. Model performance was strong (correlation between observed and predicted prevalence: 0.80-0.86; RMSE < 0.08). The estimated spatial correlation range increased from 31.93 km (95% CI: 31.92-31.94 km) in 1997-2000 to 180.20 km (95% CI: 180.20-180.20 km) in 2021-2024. Mean annual temperature, rainfall in the driest quarter, elevation, and river flow accumulation were significant predictors of prevalence. These findings underscore the need for complementary approaches such as predictive modelling to strengthen the field surveys in planning and surveillance of the disease. To sustain the progress toward onchocerciasis elimination in Nigeria, there is a need for adaptive, climate-informed strategies, intensified surveillance in high-risk areas, and enhanced coordination, particularly in cross-border and hard-to-reach communities.

Indexed as

Disease EradicationOnchocerciasisAnimalsHumansIvermectinMass Drug AdministrationModels, StatisticalMonte Carlo MethodNigeriaPrevalenceSpatio-Temporal AnalysisIvermectin

Identifiers

PMID41801979
PMCPMC12981563

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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.