Between January 1 and July 20, 2025, Nigeria's Lassa fever outbreak has resulted in 822 confirmed cases and 155 deaths. The most recent data released yesterday from the Nigeria Centre for Disease Control and Prevention (NCDC) for epidemiological Week 29 (July 14-20) shows 11 new cases.The Case Fatality Rate (CFR) has climbed to 18.9%, an increase from the 17.1% reported during the same period in 2024. A total of 6,640 suspected cases have been recorded this year, with confirmed infections found in 21 states and 105 local government areas.
The NCDC report indicates that the number of new confirmed cases in Week 29 was the same as the previous week, with new infections reported in Ondo and Edo states.Over 89% of the confirmed cases are concentrated in just five states:
Ondo (32%)
Bauchi (23%)
Edo (17%)
Taraba (14%)
Ebonyi (3%)
The remaining 11% of cases are distributed among 16 other states. The outbreak has affected a wide age range, from 1 to 96 years old, but the most impacted group is 21 to 30 years old. The median age of those affected is 30. There are slightly more male cases than female, with a male-to-female ratio of 1:0.8. Although the number of new confirmed cases remained steady in Week 29, the NCDC noted that both suspected and confirmed cases for 2025 have decreased compared to the same period in 2024. No new healthcare workers were infected during Week 29.