Bionomics and Insecticide Resistance of Malaria Vector Mosquitoes in Lomami Province, Democratic Republic of the Congo

Bionomics and Insecticide Resistance of Malaria Vector Mosquitoes in Lomami Province, Democratic Republic of the Congo | 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 Bionomics and Insecticide Resistance of Malaria Vector Mosquitoes in Lomami Province, Democratic Republic of the Congo Jean-Claude Kasongo Musasa, Leonard Mutshid Ngwej, Bienfait Much'apa Mwarabu, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9227081/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 15 You are reading this latest preprint version Abstract Background Malaria remains a major public health problem in the Democratic Republic of the Congo (DRC), particularly in Lomami Province. Understanding vector ecology, mosquito biting behavior, sporozoite infection rates, and insecticide resistance is essential for guiding malaria control and elimination strategies. This study was conducted to characterize the bionomics and insecticide susceptibility of Anopheles vector populations in Lomami Province. Methods An entomological study on mosquito bionomics was conducted in July and November 2024, corresponding respectively to the dry and rainy seasons, in the Mwene-Ditu and Kanda-Kanda health zones. Human landing catches (HLC), pyrethrum spray catches (PSC), polymerase chain reaction (PCR), and circumsporozoite enzyme-linked immunosorbent assay (ELISA-CSP) were used. Insecticide susceptibility tests were also carried out in January 2025. Comparisons were performed using chi-square (χ²) and Student’s t-tests, with the significance level set at p < 0.05. Results A total of 2,299 Anopheles mosquitoes were collected by HLC and 247 by PSC, dominated by An. funestus (45.02%) and An. gambiae s.l. (44.63%) (p = 0.78). An. funestus was significantly more abundant in Kanda-Kanda (p = 0.00000008), whereas An. gambiae s.l. predominated in Mwene-Ditu (p < 0.00000001). A seasonal alternation in species dominance was observed in Mwene-Ditu (p < 0.0001). Biting behavior showed a slight overall exophagic tendency (p = 0.06), although mosquitoes were more endophagic in Mwene-Ditu and more exophagic in Kanda-Kanda (p < 0.0001). The sporozoite index increased from 4.11% to 9.48% between July and November (p = 0.0007), while the entomological inoculation rate (EIR) increased from 1.46 to 2.09 infective bites per person per night (p < 0.001). Insecticide susceptibility tests revealed resistance to deltamethrin and DDT, but full susceptibility to bendiocarb and pirimiphos-methyl. Conclusion The findings indicate high vector activity and increased malaria transmission during the rainy season. The low level of preventive measures use, particularly long-lasting insecticidal nets (LLINs), combined with marked resistance to pyrethroids, highlights the need for continuous vector surveillance, insecticide rotation in malaria control interventions, and the promotion of appropriate protective behaviors to reduce mosquito bites. Bionomics Anopheles insecticide resistance malaria Democratic Republic of the Congo Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 04 May, 2026 Reviews received at journal 04 May, 2026 Reviews received at journal 03 May, 2026 Reviews received at journal 01 May, 2026 Reviews received at journal 27 Apr, 2026 Reviews received at journal 05 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers invited by journal 30 Mar, 2026 Editor assigned by journal 27 Mar, 2026 Submission checks completed at journal 27 Mar, 2026 First submitted to journal 25 Mar, 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. 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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-9227081","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":615339912,"identity":"80dfdd5d-5fee-4524-8649-01e66db01253","order_by":0,"name":"Jean-Claude Kasongo Musasa","email":"","orcid":"","institution":"University of Mwene Ditu","correspondingAuthor":false,"prefix":"","firstName":"Jean-Claude","middleName":"Kasongo","lastName":"Musasa","suffix":""},{"id":615339914,"identity":"2f5128b6-0358-4209-beb3-dd342447067e","order_by":1,"name":"Leonard Mutshid 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