A persistent Lassa fever outbreak in Nigeria led to 215 fatalities in 2025, according to the Nigeria Centre for Disease Control and Prevention (NCDC). The NCDC’s Lassa Fever Situation Report for Epidemiological Week 52 (December 22–28, 2025) revealed a case fatality rate of 18.7%, a notable increase from 16.3% in the same period of 2024, despite a decrease in overall suspected and confirmed cases.
Out of 9,389 suspected cases, 1,148 were confirmed across 22 states and 107 local government areas. Edo State was disproportionately affected, accounting for 16% of confirmed cases nationally, ranking among the four states contributing 89% of total infections. Ondo State was the hardest hit (35%), followed by Bauchi (26%), Edo, and Taraba (12%).
Epidemiological Week 52 alone saw 27 new confirmed cases and nine deaths in Bauchi, Ondo, Ebonyi, Taraba, and Nasarawa, an increase from the previous week. Young adults aged 21-30 were the most affected, with a median age of 30 years and a male-to-female ratio of 1:0.8 among confirmed cases.
The NCDC attributed the high fatality rate to late presentation at health facilities, poor health-seeking behavior, high treatment costs, poor sanitation, and low public awareness. Response measures included deploying National Rapid Response Teams, healthcare worker training, infection control improvements, Ribavirin distribution, and expanded risk communication. No new healthcare worker infections were reported in Week 52, reflecting improved infection control.
As a new outbreak season approaches, the NCDC urges Edo and other states to sustain year-round community sensitization and advises healthcare workers to maintain vigilance for early diagnosis and treatment. Lassa fever spreads through contact with contaminated food or household items and can transmit human-to-human. The NCDC advises hygiene, proper food storage, rodent control, and early medical attention.