{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T14:10:28Z","timestamp":1789567828387,"version":"build-2803163510"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,9,30]],"date-time":"2025-09-30T00:00:00Z","timestamp":1759190400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Nigerian Institute for Medical Research Foundation","award":["NF-GMTP-24-152809"],"award-info":[{"award-number":["NF-GMTP-24-152809"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Lassa fever (LF) is an acute viral hemorrhagic fever that poses a substantial public health security threat in West Africa. The non-specific clinical presentation of LF, coupled with a lack of reliable point-of-care diagnostics, means delayed diagnosis, leading to severe complications and mortality during epidemics. A systematic review and meta-analyses were performed by conducting an extensive online search using PubMed, Web of Science, Scopus, CINAHL, and Google Scholar (PROSPERO protocol identifier number CRD42024587426). Only peer-reviewed studies written in English were included in publications from 1 September 2014, to 31 August 2024. The analysis and reporting followed PRISMA guidelines. The quality of the included studies was assessed using the critical appraisal tools developed from the Joanna Briggs Institute Systematic Review Checklist for cohort studies. We included 19 studies that contained data from 4177 patients hospitalized with LF of any age. Most included studies employed a retrospective cohort design and were conducted in Nigeria (16\/19; 84.2%). The mortality rate was highest in a Sierra Leonean study (63.0%), whereas a group-based analysis of Nigerian studies using a random-effects model identified Owo as having the highest mortality rate of 13% (95% CI: 6\u201323; I2 = 98%). The pooled mortality rate for severe LF was 19% (95% confidence interval [CI]:10\u201332). The most common complications of LF are acute kidney injury (AKI) at a pooled proportion of 19% (95% CI; 13\u201326; I2 = 89%)), followed by abnormal bleeding at a pooled proportion of 17% (95% CI; 9\u201330; I2 = 98%), and central nervous system (CNS) dysfunction at a pooled proportion of 15% (95% CI; 6\u201332; I2 = 98%). With one out of every five hospitalized LF patients likely to die in West Africa, accelerating the development of rapid diagnostic tests, licensed vaccines, and novel therapeutics is crucial. Strengthening community engagement and risk communication, developing regional treatment guidelines, decentralizing LF care units, and training healthcare workers using a harmonized curriculum will enhance early diagnosis and effective case management, thereby reducing severe complications and mortality.<\/jats:p>","DOI":"10.3390\/ijerph22101504","type":"journal-article","created":{"date-parts":[[2025,9,30]],"date-time":"2025-09-30T13:52:46Z","timestamp":1759240366000},"page":"1504","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Clinical Outcomes of Severe Lassa Fever in West Africa: A Systematic Review and Meta-Analysis"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2878-0531","authenticated-orcid":false,"given":"Azuka Patrick","family":"Okwuraiwe","sequence":"first","affiliation":[{"name":"Centre for Human Virology and Genomics, Microbiology Department, Nigerian Institute of Medical Research, Lagos 101212, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8319-1927","authenticated-orcid":false,"given":"Chizaram Anselm","family":"Onyeaghala","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, University of Port Harcourt Teaching Hospital, Port Harcourt 500001, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Obiageli Theresa","family":"Ozoude","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Veritas University, Bwari Area Council, Abuja 900106, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7088-0619","authenticated-orcid":false,"given":"Muritala Odidi","family":"Suleiman","sequence":"additional","affiliation":[{"name":"Department of Human Anatomy, Federal University, Dutse 720101, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7534-632X","authenticated-orcid":false,"given":"Samirah Nndwan","family":"Abdu-Aguye","sequence":"additional","affiliation":[{"name":"Department of Clinical Pharmacy and Pharmacy Practice, Ahmadu Bello University, Zaria 800001, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-5828-0335","authenticated-orcid":false,"given":"Nkolika Jacinta","family":"Ezekwelu","sequence":"additional","affiliation":[{"name":"Department of Community Health and Primary Care, Lagos University Teaching Hospital, Lagos 100254, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4617-8757","authenticated-orcid":false,"given":"Tolulope Amos","family":"Oyeniyi","sequence":"additional","affiliation":[{"name":"Department of Public Health and Epidemiology, Nigerian Institute of Medical Research, Lagos 101245, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9061-3622","authenticated-orcid":false,"given":"Ayodapo Oluwadare","family":"Jegede","sequence":"additional","affiliation":[{"name":"Department of Clinical Pharmacy and Pharmacy Administration, Obafemi Awolowo University, Ile-Ife 220282, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adaeze Elfrida","family":"Egwudo","sequence":"additional","affiliation":[{"name":"Department of Community Health and Primary Care, Lagos University Teaching Hospital, Lagos 100254, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oluchukwu Perpetual","family":"Okeke","sequence":"additional","affiliation":[{"name":"Nigerian Institute of Medical Research Foundation, Lagos 1000001, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-5258-1220","authenticated-orcid":false,"given":"Olunike Rebecca","family":"Abodunrin","sequence":"additional","affiliation":[{"name":"Department of Epidemiology and Biostatistics, Nanjing Medical University, Nanjing 210029, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Folahanmi Tomiwa","family":"Akinsolu","sequence":"additional","affiliation":[{"name":"Nigerian Institute of Medical Research Foundation, Lagos 1000001, Nigeria"},{"name":"Clinical Sciences Department, Lead City University, Ibadan 200255, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9577-8330","authenticated-orcid":false,"given":"Olajide Odunayo","family":"Sobande","sequence":"additional","affiliation":[{"name":"Nigerian Institute of Medical Research Foundation, Lagos 1000001, Nigeria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,30]]},"reference":[{"key":"ref_1","unstructured":"(2024, October 05). 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