The Burden of Lassa Fever among Nigerian Health Workers: A Ten-Year Review (2015-2025) of the literature.

Abstract

workers (HCWs) to nosocomial infection, morbidity, and mortality. Objective: To synthesize ten years of evidence on LF burden among Nigerian HCWs, quantify HCW infections relative to confirmed national cases where data permit, and summarize clinical outcomes and key occupational risk factors.
Methods: A narrative review was conducted using peer-reviewed studies, WHO outbreak reports, and the Nigeria Centre for Disease Control and Prevention (NCDC) Lassa fever situation reports. Descriptive statistics were extracted. Where national totals were available, we calculated HCW infection proportion among confirmed cases (HCW/confirmed), with 95% confidence intervals (Wilson method). A log-linear trend model estimated annual percent change in HCW proportion (2019, 2020, 2022–2025; excluding partial year 2021).
Results: In early 2016, the WHO reported 10 HCWs infected and 2 deaths in Nigeria (Aug 2015–May 2016). [1] During the 2016/2017 season, Nigeria recorded 788 suspected cases, 247 confirmed cases, and 117 deaths by epi week 34, with an AAR emphasizing IPC strengthening.[2] During the 2018 outbreak, a two-treatment-center HCW series documented 21 laboratory-confirmed HCW infections with CFR 23.8%, delayed testing (median 12 days), and IPC gaps.[3] In 2019, a national investigation described 19 HCW infections (2 deaths; CFR 10.5%), most linked to clinical care exposures and inadequate IPC training. [4] In national surveillance reports, HCW infections represented 2.1–5.3 per 100 confirmed cases (2019–2025), with no significant linear trend (annual percent change) 2.77%; 95% CI −22.42 to 21.87; p=0.75; calculated) [4–10]
Conclusion: LF remains a sustained occupational hazard for Nigerian HCWs. Preventable exposure, especially in outpatient/emergency and procedural settings, persists. System-level IPC programs, early triage and suspicion, reliable PPE supply, and rapid diagnostics are essential to reduce HCW infections and deaths.