Lassa fever has killed 214 people in Nigeria so far in 2026, with the case fatality rate rising sharply to 25%, the Nigeria Centre for Disease Control and Prevention (NCDC) said in its latest situation report.
The figure marks a significant increase from the 18.9% fatality rate recorded during the same period in 2025, according to the report covering Week 23 of the outbreak, which ran from June 1 to June 7, 2026.
The agency said both suspected and confirmed cases have increased compared with the same period last year, even as new confirmed infections remained steady in Week 23, matching figures recorded in Week 22.
Cases were reported in Edo, Ondo, Bauchi and Ebonyi states during the reporting period. The NCDC said no new infections among healthcare workers were recorded that week.
According to the agency, the outbreak has now spread across 23 states and 109 local government areas since January 2026.
Five states account for the vast majority of confirmed cases. Ondo State leads with 28%, followed by Bauchi with 25%, Taraba with 15%, Edo with 10% and Benue with 6%. The remaining 16% of cases are distributed across 18 other states.
The NCDC said young adults remain the most affected group, with the highest number of cases recorded among people aged 21 to 30. Patients’ ages range from 1 to 93 years, with a median age of 30.
To coordinate the response, the agency said the National Lassa Fever Multi-Partner, Multi-Sectoral Incident Management System remains activated, supporting federal, state and local government efforts to contain the outbreak.
While no new infections among healthcare workers were recorded during the week, the agency warned that the rising fatality rate and wider geographic spread indicate ongoing transmission.
The NCDC said surveillance and case management efforts are continuing across affected states as health authorities work to curb further spread of the disease.
