ONDO, Bauchi, and Edo states have emerged as the epicentres of Nigeria’s ongoing Lassa fever outbreak, accounting for 71 per cent of the 674 confirmed cases recorded nationwide between January and April 6, 2025.
This is according to the latest situation report from the Nigeria Centre for Disease Control and Prevention (NCDC), which shows that Ondo State alone contributed 30 per cent of the confirmed cases, followed by Bauchi with 25 per cent and Edo with 16 per cent.
The update, covering epidemiological week 14 (March 31 – April 6), reveals that Nigeria reported 4,025 suspected cases during the first 14 weeks of the year. Of this number, 127 people have died.
The report further stressed that 18 states have recorded at least one confirmed case across 93 Local Government Areas so far in 2025.
The NCDC described Lassa fever as an acute viral haemorrhagic fever caused by the Lassa virus, mostly through the type of rodents known as the multimammate rat or the African rat.
The disease can be spread through direct contact with urine, faeces, saliva, or the blood of infected rats or contaminated objects, faeces, saliva, or the blood of infected rats.
Person-to-person transmission can also occur through direct contact with an infected person’s blood, urine, faeces, vomitus, and other body fluids.
Fatality rate raises concern
With the reported 127 deaths recorded from 674 confirmed cases in 2025 so far, the case fatality rate (CFR) stands at 18.8 per cent, according to the situation report.
This figure, it noted, is slightly higher than the 18.5 per cent recorded during the same period in 2024.
However, the NCDC highlighted that the number of suspected cases this year had been lower than what was recorded in the same period in 2024, possibly indicating improved public awareness and response measures.
The high case and fatality rates are linked to late presentation at health facilities, poor health-seeking behaviour, and limited access to early diagnosis in high-burden states.
Youths most affected
The most affected age group falls between 21 to 30 years, with a median age of 30. The sex distribution of the confirmed cases shows a near parity, with a male-to-female ratio of 1:0.8.
While no new healthcare worker infection was recorded in the latest week, the NCDC confirmed that 20 health workers have contracted the disease in 2025.
Latest report shows an increase in confirmed cases
The latest NCDC report for week 14 indicates a slight increase in new lassa fever cases, with 15 confirmed cases recorded compared to 14 in the previous week.
The cases were reported in Ondo, Bauchi, Edo, Taraba, Ebonyi, and Gombe states, bringing the total number of states with confirmed Lassa fever cases in 2025 to 18.
Both Ondo and Bauchi recorded five cases, Edo recorded two, while Taraba and Ebonyi recorded one each in week 14.
This also means that Ondo has 200 confirmed cases of the disease in 2025, followed by Bauchi with 171, Edo with 107, and Taraba with 106.
Ebonyi (21), Kogi (14), Plateau (13), Gombe (13), Benue (9), and Nasarawa (5) make the top 10 most affected states.
Usman Mustapha is a solution journalist with International Centre for Investigative Reporting. You can easily reach him via: umustapha@icirnigeria.com. He tweets @UsmanMustapha_M