The Nigeria Centre for Disease Control and Prevention (NCDC) has confirmed 717 cases of Lassa fever from 4,881 suspected cases reported between January and May 4, 2025.
These cases span 18 states and 93 local government areas, according to the latest NCDC situation report released on Wednesday.
Tragically, 138 deaths have been recorded, yielding a Case Fatality Rate (CFR) of 19.3 percent. The states hardest hit include Ondo with 27 deaths, Taraba with 34, Edo with 19, and Bauchi with 15, among others. The full list of states reporting fatalities also features Ebonyi, Kogi, Gombe, Plateau, Benue, Nasarawa, Kaduna, Enugu, Delta, Cross-River, and Ogun.
Lassa fever, an acute viral hemorrhagic illness caused by the Lassa virus, primarily spreads through contact with the multimammate rat, the virus’s natural reservoir. Other rodents may also carry the virus.
The report noted, “In week 18, the number of new confirmed cases decreased slightly from 11 in epidemiological week 17 to 10 cases reported in Ondo, Edo, Bauchi, and Benue States.” Cumulatively, the CFR of 19.2 percent in 2025 is higher than the 18.0 percent recorded in the same period last year.
Notably, 71 percent of all confirmed cases are concentrated in three states: Ondo (30 percent), Bauchi (25 percent), and Taraba (16 percent). The remaining 28 percent are distributed among 15 other states.
The predominant age group affected is 21 to 30 years, with a median age of 30, and the male-to-female ratio stands at 1:0.8. Encouragingly, no new healthcare workers were infected in the latest reporting week.
The NCDC continues to coordinate response efforts through a multi-sectoral Incident Management System activated nationwide to combat the outbreak effectively.
