Deciphering the dynamics of Lassa fever outbreak in Edo State, Nigeria: A 3-year study of the epidemiologic patterns, severity profiles, and clinical management

<h2>Abstract</h2><h3>Objectives</h3> Nigeria has the highest prevalence of Lassa fever (LF) in West Africa, with Edo State being a high-burden area. This study describes the epidemiology and management of LF in Edo State. <h3>Methods</h3> A desk analysis of LF cases from the Irrua Specialist Teaching Hospital (ISTH) records from January 2021 to November 2023 was conducted. The outcome variables were case outcome and severity, classified using the 2018 Nigeria Centre for Disease Control and Prevention LF guide. Bivariate and logistic regression analyses were conducted at α <0.05. <h3>Results</h3> Of the 10,432 suspected cases, 1296 (12.4 %) were confirmed, with 964 (74.4 %) occurring during the dry season. The median age was 26 (interquartile range 15–40) years, and 687 (53.0 %) were male. The location distribution pattern of the confirmed cases was clustered, with one-third (34.3 %) from Etsako West. Older age (adjusted odds ratio 2.2, 95 % confidence interval: 1.2–4.0) and more than five symptoms (adjusted odds ratio 9.5, 95 % confidence interval: 6.9–13.1) were associated with severe LF and increased odds of in-hospital death. Hospital presentation time was not associated with LF severity or outcomes. LF confirmation at ISTH was within 24 hours. <h3>Conclusions</h3> Older patients with more than five symptoms should be prioritized in LF management, and the ISTH-LF care algorithm is effective.