Assessment of the relationship between gametocyte density, multiplicity of infection and mosquito infectivity in Plasmodium falciparum infections

Assessment of the relationship between gametocyte density, multiplicity of infection and mosquito infectivity in Plasmodium falciparum infections | 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 Assessment of the relationship between gametocyte density, multiplicity of infection and mosquito infectivity in Plasmodium falciparum infections Abdoulie Touray, Victor Atunga Mobegi, Fred Wamunyokoli, Hellen Butungi, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-33602/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Malaria is a major public health threat in sub-Saharan Africa. Asymptomatic P. falciparum gametocyte carriers are potential infectious reservoirs for sustaining transmission in many malaria endemic regions. The aim of the study was to assess the prevalence of gametocyte carriage and some of its associated risk factors among asymptomatic schoolchildren (age 5-15 years) in Mbita, western Kenya and further analyse the association between gametocyte density, multiplicity of infection (MOI) and mosquito infectivity. Methods: Rapid diagnostic test (RDT) was used to screen for P. falciparum parasite infection among asymptomatic schoolchildren (5-15 years old) residing in Mbita, Western Kenya and the results were further verified using microscopy. Participants positive for P. falciparum infection were further screened for gametocyte carriage and those positive were used to feed laboratory reared An. gambiae s.s. mosquitoes using membrane feeding method. Genomic DNA was extracted from dry blood spots (DBS) samples and P. falciparum populations were genotyped using 10 polymorphic microsatellite markers. Assessment of the association between MOI and gametocyte density and mosquito infection rates was conducted. Results: The prevalence of Plasmodium falciparum infection among the study population was 29.1%. A significantly higher P. falciparum infection was found among the male gender (n=764, p -value < 0.05) compared to the females (n=657). Gametocyte prevalence among the study population was 2%. Children (5-9 years) have a higher risk of gametocyte carriage (Odd Ratios = 2.1 [95% CI = 1.3–3.4], P = 0.002). Our results indicate a significant and positive combined effect of gametocyte density and MOI on mosquito infection rate (R = 0.825, p < 0.0001). Conclusion: The study reports a relatively stable year-round gametocyte carriage among the study population. This pattern of gametocyte carriage signals the role of schoolchildren in maintaining malaria transmission in the study area. A strong positive correlation was found between gametocyte density, multiplicity of infection and mosquito infectivity. Infectious Diseases P. falciparum asymptomatic gametocyte density MOI mosquito infection rates Mbita Figures Figure 1 Figure 2 Figure 3 Full Text Supplementary Files Additionalfile1.docx Additionalfile2.docx Cite Share Download PDF Status: Posted 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-33602","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research","associatedPublications":[],"authors":[{"id":644255,"identity":"13d40e2a-56bf-4664-ab96-f502d130f33f","order_by":0,"name":"Abdoulie Touray","email":"","orcid":"","institution":"PAUSTI","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Abdoulie","middleName":"","lastName":"Touray","suffix":""},{"id":644256,"identity":"23b2e989-fb5f-48a6-9d70-5313d867e620","order_by":1,"name":"Victor Atunga Mobegi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYHACNiCWkAOxDjwgRYsxWEsCCVoYEhtAJFFaDK4dPvbgwy+L9Plhhx8CbbGT020gpOV2WrrhzD6J3I230wyAWpKNzQ4Q0CI5O8dMmrcHqGV2AkjLgcRtRGn52yORbjg7/QNxWvilgVoYfkgkyEvnEGkLvzTQL70NEoYbpHMKDiQYEOEXNunkYw9+/KmTl5+dvvnDhwo7OYJawICxDRh0YJUGxCgHgz8MDPINRKseBaNgFIyCkQYAy1pEp4Z7RacAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-1962-5583","institution":"University of Nairobi","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Victor","middleName":"Atunga","lastName":"Mobegi","suffix":""},{"id":644257,"identity":"599623dd-702e-4656-8fc3-84d2b6a5c3eb","order_by":2,"name":"Fred Wamunyokoli","email":"","orcid":"","institution":"Jomo Kenyatta University of Agriculture and Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Fred","middleName":"","lastName":"Wamunyokoli","suffix":""},{"id":644258,"identity":"af1499ed-f940-4023-8125-be34ca28a746","order_by":3,"name":"Hellen Butungi","email":"","orcid":"","institution":"International Centre for Insect Physiology and Ecology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hellen","middleName":"","lastName":"Butungi","suffix":""},{"id":644259,"identity":"4c36e682-0e3e-4767-86a8-5090650de131","order_by":4,"name":"Jeremy K. Herren","email":"","orcid":"","institution":"International Centre for Insect Physiology and Ecology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jeremy","middleName":"K.","lastName":"Herren","suffix":""}],"badges":[],"createdAt":"2020-06-05 14:29:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-33602/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-33602/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":1287194,"identity":"0a9a5844-6d09-4f86-b574-c2339598a312","added_by":"auto","created_at":"2020-06-09 14:18:52","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":122142,"visible":true,"origin":"","legend":"Map of Homa Bay County indicating the prevalence of Plasmodium falciparum infection among the schools in the study site. The site-specific prevalence (%) was calculated as the percentage of P. falciparum positive infections within each school.","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-33602/v1/1.jpg"},{"id":1287195,"identity":"023bfec0-8afe-4e80-b4bf-985aab8846f5","added_by":"auto","created_at":"2020-06-09 14:18:52","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":92892,"visible":true,"origin":"","legend":"P. falciparum infection (blue) and gametocyte (brown) prevalence among the study participants and average rainfall (gray) during the various sampling periods.","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-33602/v1/2.jpg"},{"id":1287196,"identity":"22cbed5e-5361-4c17-8b79-81954fba30d1","added_by":"auto","created_at":"2020-06-09 14:18:52","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":133895,"visible":true,"origin":"","legend":"Relationship between gametocyte density (gametocyte/μl) and multiplicity of infection (MOI) with mosquito infection rate.","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-33602/v1/3.jpg"},{"id":1287200,"identity":"ba641d39-651e-48a9-8727-1f8655098999","added_by":"auto","created_at":"2020-06-09 14:18:54","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":497132,"visible":true,"origin":"","legend":"","description":"","filename":"AssessmentofgametocytedensityMOIMosquitoinfectivity.pdf","url":"https://assets-eu.researchsquare.com/files/rs-33602/v1_stamped.pdf"},{"id":1287197,"identity":"275bd9fa-02d6-48de-889d-07b989da917b","added_by":"auto","created_at":"2020-06-09 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14:18:52","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":14028,"visible":true,"origin":"","legend":"","description":"","filename":"Additionalfile1.docx","url":"https://assets-eu.researchsquare.com/files/rs-33602/v1/Additionalfile1.docx"},{"id":1287199,"identity":"ce604e46-8ee5-4a54-9311-84341015b286","added_by":"auto","created_at":"2020-06-09 14:18:53","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":16439,"visible":true,"origin":"","legend":"","description":"","filename":"Additionalfile2.docx","url":"https://assets-eu.researchsquare.com/files/rs-33602/v1/Additionalfile2.docx"}],"financialInterests":"","formattedTitle":"\u003cp\u003eAssessment of the relationship between gametocyte density, multiplicity of infection and mosquito infectivity in \u003cem\u003ePlasmodium falciparum\u003c/em\u003e infections\u003c/p\u003e","fulltext":[{"header":"Full Text","content":"\u003cp\u003eThis preprint is available for \u003ca href='/article/rs-33602/latest.pdf' target='_blank'\u003edownload as a PDF\u003c/a\u003e.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"P. falciparum, asymptomatic, gametocyte density, MOI, mosquito infection rates, Mbita","lastPublishedDoi":"10.21203/rs.3.rs-33602/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-33602/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eMalaria is a major public health threat in sub-Saharan Africa. Asymptomatic P. falciparum gametocyte carriers are potential infectious reservoirs for sustaining transmission in many malaria endemic regions. The aim of the study was to assess the prevalence of gametocyte carriage and some of its associated risk factors among asymptomatic schoolchildren (age 5-15 years) in Mbita, western Kenya and further analyse the association between gametocyte density, multiplicity of infection (MOI) and mosquito infectivity. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Rapid diagnostic test (RDT) was used to screen for P. falciparum parasite infection among asymptomatic schoolchildren (5-15 years old) residing in Mbita, Western Kenya and the results were further verified using microscopy. Participants positive for P. falciparum infection were further screened for gametocyte carriage and those positive were used to feed laboratory reared An. gambiae s.s. mosquitoes using membrane feeding method. Genomic DNA was extracted from dry blood spots (DBS) samples and P. falciparum populations were genotyped using 10 polymorphic microsatellite markers. Assessment of the association between MOI and gametocyte density and mosquito infection rates was conducted. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe prevalence of Plasmodium falciparum infection among the study population was 29.1%. A significantly higher P. falciparum infection was found among the male gender (n=764, p -value \u0026lt; 0.05) compared to the females (n=657). Gametocyte prevalence among the study population was 2%. Children (5-9 years) have a higher risk of gametocyte carriage (Odd Ratios = 2.1 [95% CI = 1.3–3.4], P = 0.002). Our results indicate a significant and positive combined effect of gametocyte density and MOI on mosquito infection rate (R = 0.825, p\u0026nbsp;\u0026lt;\u0026nbsp;0.0001). \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eThe study reports a relatively stable year-round gametocyte carriage among the study population. This pattern of gametocyte carriage signals the role of schoolchildren in maintaining malaria transmission in the study area. A strong positive correlation was found between gametocyte density, multiplicity of infection and mosquito infectivity.\u003c/p\u003e","manuscriptTitle":"Assessment of the relationship between gametocyte density, multiplicity of infection and mosquito infectivity in Plasmodium falciparum infections","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2020-06-09 14:18:51","doi":"10.21203/rs.3.rs-33602/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4427875a-e050-431a-a311-a4db00b908f3","owner":[],"postedDate":"June 9th, 2020","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":116189,"name":"Infectious Diseases"}],"tags":[],"updatedAt":"2020-07-05T16:04:10+00:00","versionOfRecord":[],"versionCreatedAt":"2020-06-09 14:18:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-33602","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-33602","identity":"rs-33602","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}