Where did the nets go? – Tracing bed net migration on Bioko Island

Where did the nets go? – Tracing bed net migration on Bioko Island | 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 Research Article Where did the nets go? – Tracing bed net migration on Bioko Island Thomas C Stabler, Liyu A Teklemichael, Jeremias Nzamio Mba Eyono, and 10 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8662839/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 10 You are reading this latest preprint version Abstract Background. Long-lasting insecticidal nets (LLINs) are commonly distributed through mass distribution campaigns (MDCs). MDCs are commonly followed by substantial loss of LLINs, affecting coverage. Here, data from an MDC and a malaria indicator survey (MIS) on Bioko Island were used to characterize LLIN mobility. Methods. Between October 2014 and July 2015, an MDC reached most of the households of the island. Distributed nets were marked with a unique code corresponding to the community where they were distributed. An MIS conducted in August and September 2015 allowed to measure LLIN loss and mobility by verifying the number of existing nets and their community code. Multivariate models identified factors associated with LLINs with mismatched codes. A source-sink analysis measuring risk gradient between the source community and the sink household was used to assess the overall effect of migrating nets. Results. The MIS revealed that 40.4% of LLINs distributed during the MDC had been lost. Among the surviving nets (7,393/12,397), community codes were visible only for 3,413 (46.2%), and 551 (16.1%) revealed a mismatched code. The factor most strongly associated with mismatched LLINs was open eaves (OR: 1.88; 95% CI: 1.48 – 2.38, p < 0.001). The source sink analysis showed that while the majority of LLINs migrated from lower to higher risk areas (62.3%), almost a third migrated in the opposite direction. Conclusion. While redistribution had a positive impact on some communities by serving populations at higher risk of transmission, many households in high-risk areas lost their nets to areas with lower risk. This, coupled with the significant LLIN loss post-MDC, pointed to critical inefficiencies and prompted a shift in LLIN distribution strategy from MDC to demand-driven fixed distribution points. malaria LLIN distribution LLIN migration Bioko Island Full Text Additional Declarations No competing interests reported. Supplementary Files SupplementaryTables.xlsx Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 05 May, 2026 Reviews received at journal 17 Apr, 2026 Reviewers agreed at journal 16 Apr, 2026 Reviewers agreed at journal 14 Apr, 2026 Reviews received at journal 12 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers invited by journal 06 Mar, 2026 Editor assigned by journal 22 Jan, 2026 Submission checks completed at journal 22 Jan, 2026 First submitted to journal 21 Jan, 2026 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-8662839","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":601865388,"identity":"36491bd9-7d6f-4daf-8ef0-0cc2c9e5a90e","order_by":0,"name":"Thomas C 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MDCs are commonly followed by substantial loss of LLINs, affecting coverage. Here, data from an MDC and a malaria indicator survey (MIS) on Bioko Island were used to characterize LLIN mobility.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods. \u003c/strong\u003eBetween October 2014 and July 2015, an MDC reached most of the households of the island. Distributed nets were marked with a unique code corresponding to the community where they were distributed. An MIS conducted in August and September 2015 allowed to measure LLIN loss and mobility by verifying the number of existing nets and their community code. Multivariate models identified factors associated with LLINs with mismatched codes. A source-sink analysis measuring risk gradient between the source community and the sink household was used to assess the overall effect of migrating nets.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults. \u003c/strong\u003eThe MIS revealed that 40.4% of LLINs distributed during the MDC had been lost. Among the surviving nets (7,393/12,397), community codes were visible only for 3,413 (46.2%), and 551 (16.1%) revealed a mismatched code. The factor most strongly associated with mismatched LLINs was open eaves (OR: 1.88; 95% CI: 1.48 – 2.38, p \u0026lt; 0.001). The source sink analysis showed that while the majority of LLINs migrated from lower to higher risk areas (62.3%), almost a third migrated in the opposite direction.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion. \u003c/strong\u003eWhile redistribution had a positive impact on some communities by serving populations at higher risk of transmission, many households in high-risk areas lost their nets to areas with lower risk. This, coupled with the significant LLIN loss post-MDC, pointed to critical inefficiencies and prompted a shift in LLIN distribution strategy from MDC to demand-driven fixed distribution points.\u003c/p\u003e","manuscriptTitle":"Where did the nets go? – Tracing bed net migration on Bioko Island","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-11 18:51:15","doi":"10.21203/rs.3.rs-8662839/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-05T22:07:21+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-17T08:01:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"224718140149292023800357525831746596404","date":"2026-04-17T02:41:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"74249758994196530255411600898208024077","date":"2026-04-14T08:58:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-12T12:11:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"283911516923979439742038641673493830090","date":"2026-03-06T10:08:44+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-06T09:29:10+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-23T03:02:27+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-22T17:58:52+00:00","index":"","fulltext":""},{"type":"submitted","content":"Malaria Journal","date":"2026-01-21T18:23:48+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"malaria-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"malj","sideBox":"Learn more about [Malaria Journal](http://malariajournal.biomedcentral.com/)","snPcode":"12936","submissionUrl":"https://submission.nature.com/new-submission/12936/3","title":"Malaria Journal","twitterHandle":"@malariajournal","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b4f06d95-1640-4cf2-85d4-86252795466f","owner":[],"postedDate":"March 11th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-05T22:07:21+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T22:23:31+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-11 18:51:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8662839","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8662839","identity":"rs-8662839","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}