The Nigeria Centre for Disease Control and Prevention (NCDC) has reported 413 confirmed cases of Lassa fever in the latest outbreak, which began in January 2025. At least 80 deaths have been reported in 11 states of Nigeria, resulting in a case fatality rate (CFR) of 19.4 percent. Ondo, a state in southwestern Nigeria, has been particularly badly affected, accounting for at least 34 percent of the total confirmed cases. The outbreak has spread to 63 of the country’s 774 local government areas, predominantly affecting individuals between the ages of 21 and 30. Consequently, the NCDC has initiated a multi-sectoral incident management system to harmonize response activities at the national level. Principal actions involve educating healthcare professionals in the clinical management of Lassa fever, improving monitoring and contact identification in impacted states, and providing personal protective equipment.
Lassa fever, a viral illness caused by the Lassa virus, is contracted through exposure to materials or bodily fluids contaminated by infected rodents. Symptomatic presentation of the disease occurs in approximately 20% of those infected, with the majority of cases exhibiting a mild form of the infection. Nevertheless, in approximately twenty percent of instances, the infection may result in serious illness, affecting the liver, spleen, and kidneys. According to health sources, Nigeria reported 214 deaths from Lassa fever in 2024.
