{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T10:12:52Z","timestamp":1790503972544,"version":"4.1.0"},"reference-count":41,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,5]],"date-time":"2021-01-05T00:00:00Z","timestamp":1609804800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["ref BO 3790\/1&2-1, FI 1781\/1&2-1"],"award-info":[{"award-number":["ref BO 3790\/1&2-1, FI 1781\/1&2-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"name":"PANDORA-ID-NET EDCTP","award":["RIA2016E-1609"],"award-info":[{"award-number":["RIA2016E-1609"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biology"],"abstract":"<jats:p>Lassa fever is a viral hemorrhagic fever caused by the Lassa virus LASV, which was first isolated in the rodent Mastomys natalensis in 1974 in Kenema, Sierra Leone. As little is known about the abundance and the presence of LASV in rodents living in the Bo area, we carried out a small mammal longitudinal population survey. A standardized trapping session was performed in various habitats and seasons in six villages over two years (2014\u20132016) and samples collected were tested for arenavirus IgG and LASV. A Bayesian phylogenetic analysis was performed on sequences identified by PCR. A total of 1490 small mammals were collected, and 16 rodent species were identified, with M. natalensis (355, 24%) found to be the most prevalent species. Forty-one (2.8%) samples were IgG positive, and 31 of these were trapped in homes and 10 in surrounding vegetation. Twenty-nine of 41 seropositive rodents were M. natalensis. We detected four LASV by PCR in two villages, all found in M. natalensis. Phylogenetic analysis showed that the sequences were distributed within the Sierra Leonean clade within lineage IV, distinguishing a Bo sub-clade older than a Kenema sub-clade. Compared to other settings, we found a low abundance of M. natalensis and a low circulation of LASV in rodents in villages around Bo district.<\/jats:p>","DOI":"10.3390\/biology10010028","type":"journal-article","created":{"date-parts":[[2021,1,5]],"date-time":"2021-01-05T10:35:12Z","timestamp":1609842912000},"page":"28","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Lassa Virus Circulation in Small Mammal Populations in Bo District, Sierra Leone"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8789-3187","authenticated-orcid":false,"given":"Umaru","family":"Bangura","sequence":"first","affiliation":[{"name":"Mercy Hospital Research Laboratory, Bo, Sierra Leone"},{"name":"Department of Virology, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacob","family":"Buanie","sequence":"additional","affiliation":[{"name":"Mercy Hospital Research Laboratory, Bo, Sierra Leone"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joyce","family":"Lamin","sequence":"additional","affiliation":[{"name":"Mercy Hospital Research Laboratory, Bo, Sierra Leone"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Davis","sequence":"additional","affiliation":[{"name":"Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G\u00e9d\u00e9on Ngiala","family":"Bongo","sequence":"additional","affiliation":[{"name":"Department of Virology, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Dawson","sequence":"additional","affiliation":[{"name":"Mercy Hospital Research Laboratory, Bo, Sierra Leone"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rashid","family":"Ansumana","sequence":"additional","affiliation":[{"name":"Mercy Hospital Research Laboratory, Bo, Sierra Leone"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dianah","family":"Sondufu","sequence":"additional","affiliation":[{"name":"Mercy Hospital Research Laboratory, Bo, Sierra Leone"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emma C.","family":"Thomson","sequence":"additional","affiliation":[{"name":"Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Foday","family":"Sahr","sequence":"additional","affiliation":[{"name":"College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown PMB 595, Sierra Leone"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabeth","family":"Fichet-Calvet","sequence":"additional","affiliation":[{"name":"Department of Virology, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,5]]},"reference":[{"key":"ref_1","first-page":"197","article-title":"Lassa fever encephalopathy: Clinical and laboratory findings","volume":"95","author":"Cummins","year":"1992","journal-title":"J. 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