The Nigeria Centre for Disease Control and Prevention (NCDC) is closely monitoring 1,277 individuals who may have been exposed to Lassa fever, following a sharp rise in confirmed cases and fatalities across the country.
Between January and March 30, 2025, the NCDC recorded 659 confirmed cases of Lassa fever out of 3,779 suspected cases. The death toll stands at 122, according to a report released on Friday.
At least 18 states have reported Lassa fever cases, with Ondo, Bauchi, and Edo accounting for the majority. The report revealed:
> “As of week 13, a total of 122 deaths have been reported, with a Case Fatality Rate (CFR) of 18.5%, slightly lower than the CFR of 18.7% for the same period in 2024.”
The confirmed cases were spread across 93 local government areas in the 18 affected states. Notably, 71% of all confirmed cases came from Ondo (30%), Bauchi (25%), and Edo (16%). The remaining 29% were distributed among 15 other states.
Most affected individuals fall within the 21–30 age group, with patients ranging from 1 to 94 years old. The male-to-female ratio among confirmed cases is 1:0.8.
The report also shows a year-on-year increase in suspected cases. So far, 20 healthcare workers in eight states have been infected in 2025. However, no new infections among health workers were recorded in week 13.
The NCDC has activated its multi-partner, multi-sectoral Incident Management System (IMS) to coordinate the national response.
The report also noted that 1,448 people have completed the mandatory follow-up process, while 1,277 are still under observation.
Lassa fever is a viral hemorrhagic illness caused by the Lassa virus, commonly spread through contact with the urine or feces of infected multimammate rats. While infections occur year-round, the peak transmission season spans from October to May.
