Nigeria’s confirmed Lassa fever death toll has risen to 258 in 2026, with the cumulative case-fatality rate reaching 24.0%, according to the latest surveillance report from the Nigeria Centre for Disease Control and Prevention.
The NCDC’s Epidemiological Week 35 report, covering August 24 to 30, recorded 18 new laboratory-confirmed cases. That brought the country’s cumulative total for the year to 1,074 confirmed infections across 24 states.
The newly confirmed cases were reported in Ondo, Edo and Bauchi states. The weekly figure was down from 21 cases in Epidemiological Week 34, a decrease of three cases, or about 14%.
Despite that week-on-week decline, the cumulative proportion of confirmed patients who have died remained markedly higher than during the comparable period last year. The 24.0% case-fatality rate through Week 35 was 5.4 percentage points above the 18.6% recorded at the same stage of 2025.
“Cumulatively, 258 deaths have been reported with a Case Fatality Rate (CFR) of 24.0%,” the NCDC said, according to Vanguard.
Deaths exceed last year’s comparable total
By Epidemiological Week 35 of 2025, Nigeria had reported 162 deaths among confirmed Lassa fever cases. The 2026 total is therefore 96 deaths higher, representing an increase of about 59% from the comparable figure last year.
The rise in confirmed-case deaths has occurred alongside an increase in the number of suspected infections submitted to the national surveillance system. Nigeria recorded 7,785 suspected Lassa fever cases through Week 35 of 2026, compared with 7,375 during the corresponding period in 2025.
That amounts to 410 more suspected cases than at the same point last year, an increase of approximately 5.6%. Laboratory testing had confirmed 1,074 of the suspected cases reported so far in 2026.
The NCDC figures distinguish suspected cases from laboratory-confirmed infections and calculate the reported case-fatality rate using confirmed cases and deaths among confirmed patients.
Five states account for most confirmed cases
The geographic distribution of infections remained heavily concentrated. Five states accounted for 86% of all confirmed Lassa fever cases recorded in Nigeria through Epidemiological Week 35.
Ondo had the largest share, accounting for 34% of the national confirmed-case total. Bauchi followed with 24%, while Taraba accounted for 12%. Edo represented 10% of confirmed cases and Benue accounted for 6%.
Together, Ondo and Bauchi alone represented 58% of the country’s confirmed infections. The remaining 14% of cases were distributed among the other 19 states that had reported confirmed infections during the year.
Three of the five states with the highest cumulative shares—Ondo, Bauchi and Edo—also reported all 18 of the new cases detected in Week 35. The available figures did not provide a state-by-state breakdown of those 18 infections.
No new infection among health workers
No new healthcare-worker infection was reported during Epidemiological Week 35. The cumulative number of healthcare workers affected by Lassa fever in Nigeria during 2026 remained at 54.
The latest report captures the outbreak’s position at the end of August and does not include infections, deaths or suspected cases reported after August 30. Based on the Week 35 totals, Nigeria had recorded more suspected cases and more confirmed-case deaths than during the corresponding period of 2025, while the national case-fatality rate had also increased.
Although new laboratory-confirmed cases declined from the previous week, the year-to-date data show that the outbreak continued to affect multiple states, with the large majority of confirmed infections concentrated in five of them.
