Onchocerciasis-associated skin and ocular disease and the impact of ivermectin treatment on morbidity prevalence: a modelling study

Onchocerciasis-associated skin and ocular disease and the impact of ivermectin treatment on morbidity prevalence: a modelling study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Onchocerciasis-associated skin and ocular disease and the impact of ivermectin treatment on morbidity prevalence: a modelling study Matthew Dixon, Aditya Ramani, Martin Walker, Jacob Stapley, Michele Murdoch, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6992326/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Mar, 2026 Read the published version in Communications Medicine → Version 1 posted You are reading this latest preprint version Abstract Background Despite decades of control interventions in sub-Saharan Africa, morbidity associated with Onchocerca volvulus infection still exerts a substantial burden of disease, arising from cutaneous, ocular and neurological manifestations. Methods We developed and integrated a morbidity sub-model into our previously published individual-based, stochastic transmission model, EPIONCHO-IBM, including both reversible (severe itch, reactive skin disease (RSD)), and irreversible (atrophy, depigmentation, hanging groin) cutaneous sequelae, and eye disease (blindness, visual impairment). We modelled the relationship between onchocerciasis skin disease (OSD) and infection prevalence using pre-intervention data from northern Nigeria, and between onchocerciasis ocular disease (OOD) and infection intensity using data from the Onchocerciasis Control Programme in West Africa. We simulated the impact of ivermectin mass drug administration (MDA) upon OSD and OOD using data from Cameroon, Central African Republic, Nigeria, Sudan and Uganda. Results Modelled age-specific OSD and OOD prevalence at baseline aligned well with reported prevalence estimates across the simulated range of endemicity levels but underestimated irreversible OSD in older age groups. Under MDA, we captured trends in infection prevalence, severe itch and irreversible OSD but underestimated reductions in RSD and blindness prevalence. Conclusions Integrating morbidity outcomes into transmission dynamics modelling will help improve estimates of onchocerciasis disease burden and inform the effectiveness and cost-effectiveness of current and alternative interventions. Health sciences/Diseases/Infectious diseases/Parasitic infection Biological sciences/Computational biology and bioinformatics onchocerciasis morbidity modelling ivermectin sub-Saharan Africa Full Text Additional Declarations There is NO Competing Interest. Supplementary Files Dixonetal.ModellingMorbiditySuppl27.06.2025.pdf Supplementary Information: Onchocerciasis-associated skin and ocular disease and the impact of ivermectin treatment on morbidity prevalence: a modelling study reportingsummary.pdf Reporting Summary Cite Share Download PDF Status: Published Journal Publication published 02 Mar, 2026 Read the published version in Communications Medicine → Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6992326","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":480349793,"identity":"bdf0f975-d1c0-49f4-b569-7ba4bc5b9fa5","order_by":0,"name":"Matthew 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