A hemorrhagic fever that kills approximately one in four hospitalized patients is surging in Nigeria in 2026, and American travelers who have recently returned from West Africa may be carrying it without knowing it. As of the end of March 2026, the Nigeria Centre for Disease Control and Prevention (NCDC) confirmed 663 Lassa fever cases and 167 deaths across 22 states and 93 local government areas — with a case fatality rate of 25.2 percent, a sharply elevated figure compared to 18.5 percent during the same period in 2025 and significantly higher than Nigeria's typical baseline.
The outbreak has infected 39 healthcare workers, including physicians, with reported deaths among clinical staff — a signal that infection prevention and control (IPC) measures in healthcare settings are being overwhelmed or inconsistently applied. Eighty-five percent of confirmed cases are concentrated in five states: Bauchi, Ondo, Taraba, Benue, and Edo, but the geographic spread — 22 states — confirms the outbreak has moved well beyond Nigeria's traditional Lassa-endemic core.
