Ondo, Bauchi, Edo, Taraba, and Ebonyi states have accounted for 90% of all confirmed Lassa fever cases in Nigeria so far in 2025, according to the latest situation report by the Nigeria Centre for Disease Control and Prevention (NCDC).
The agency disclosed this in its latest Epidemiological Week 21 report, published on its official website on Sunday.
The report confirmed Nigeria has recorded 739 confirmed Lassa fever cases and 141 deaths, resulting in a case fatality ratio (CFR) of 19.1%, a slight increase from the 18.1% CFR reported during the same period in 2024.
In comparison, by Week 21 of 2024, the country had logged 897 confirmed cases and 162 deaths, indicating a decline in both suspected and confirmed cases this year, but a marginal rise in the fatality rate.
Geographic spread of the outbreak
So far in 2025, 18 states across 95 Local Government Areas (LGAs) have reported at least one confirmed case, compared to 28 states and 125 LGAs during the same period last year.
Five states—Ondo, Bauchi, Edo, Taraba, and Ebonyi—continue to drive the Lassa fever outbreak in Nigeria, accounting for 90% of all confirmed cases. Ondo alone reported 30% of total confirmed infections, followed by Bauchi (25%), Edo (16%), Taraba (16%), and Ebonyi (3%).
So far in 2025, the country has recorded 141 deaths, with a Case Fatality Rate (CFR) of 19.1%.
Confirmed cases have been reported in the following states: Ondo (224); Bauchi (185); Edo (121); Taraba (116); Ebonyi (21); Kogi (15); Gombe (14); Plateau (13); Benue (11); Nasarawa (5); Kaduna (3); Enugu (3); Delta (2); Cross River (2); Borno (1); Ogun (1); Federal Capital Territory (1); and Anambra (1).
Deaths by State
Deaths have been reported in Ondo (28); Bauchi (16); Edo (20); Taraba (34); Ebonyi (11); Kogi (4); Gombe (7); Plateau (5); Benue (5); Nasarawa (4); Kaduna (2); Enugu (1); Delta (2); Cross River (1); and Ogun (1).
According to the agency, the disease predominantly affects individuals aged 21 to 30 years, with a median age of 30. The male-to-female ratio among confirmed cases is 1:0.8, indicating a slightly higher infection rate among males.
“Notably, no healthcare workers were affected during the latest reporting week. However, 22 healthcare workers have been infected so far in 2025,” the NCDC stated.
The NCDC confirmed that a national multi-partner, multi-sectoral Incident Management System (IMS) remains active in coordinating ongoing response efforts across the country.
More Insight
Lassa fever is a viral hemorrhagic disease caused by the Lassa virus, primarily transmitted through contact with food or household items contaminated by the urine, feces, or saliva of infected rodents.
Human-to-human transmission can also occur, particularly in healthcare settings with inadequate infection prevention and control (IPC) measures.
The NCDC identified several challenges affecting the outbreak response, including the late presentation of cases, which has contributed to high fatality rates.
It also highlighted poor health-seeking behavior, largely due to the high cost of Lassa fever treatment and management.
Additionally, poor environmental sanitation in high-burden communities and low awareness of Lassa fever symptoms and preventive measures were noted as key issues.
