Nigeria's Lassa fever outbreak reaches 252 deaths with case fatality rate of 24.4%

Nigeria's Lassa fever outbreak has escalated to 252 deaths from 1,035 confirmed cases as of August 2026, yielding a high case fatality rate of 24.4%. Five states, led by Ondo and Bauchi, account for 87% of these cases. To combat the spread and protect 54 infected healthcare workers, the Nigeria Centre for Disease Control and Prevention has launched a 30-day protection plan with international support, targeting late clinical presentation and poor sanitation.

Lassa fever outbreak statistics

• ▪As of epidemiological week 33, ending August 16, 2026, Nigeria recorded 252 deaths from 1,035 confirmed Lassa fever cases, representing a case fatality rate of 24.4 percent.
• ▪The 24.4 percent case fatality rate for Lassa fever in Nigeria as of August 2026 is higher than the 18.6 percent rate recorded during the same period in 2025.
• ▪Nigeria recorded 14 new confirmed Lassa fever cases between August 10 and 16, 2026, representing an increase from the four cases reported in the preceding week.
• ▪The cumulative number of suspected Lassa fever cases in Nigeria reached 7,426, with six probable cases recorded as of epidemiological week 33 in 2026.

Five states concentration pattern

• ▪Five Nigerian states—Ondo, Bauchi, Taraba, Edo, and Benue—accounted for 87 percent of all confirmed Lassa fever cases recorded nationally as of August 2026.
• ▪As of epidemiological week 33 in 2026, at least one confirmed Lassa fever case had been recorded across 23 states and 117 Local Government Areas in Nigeria.
• ▪As of August 2026, Ondo State accounted for 33 percent of Nigeria's confirmed Lassa fever cases, followed by Bauchi State with 25 percent, Taraba State with 13 percent, Edo State with 10 percent, and Benue State with six percent.

Healthcare worker infections

• ▪A cumulative total of 54 healthcare workers in Nigeria have been infected with Lassa fever in 2026, though no new healthcare worker infections were reported between August 10 and 16, 2026.
• ▪The Nigeria Centre for Disease Control and Prevention identified late clinical presentation, high treatment costs, poor sanitation, low community awareness, and healthcare-worker infections as major challenges in managing the Lassa fever outbreak.

Transmission through contaminated materials

• ▪Lassa fever is an acute viral hemorrhagic illness primarily transmitted to humans through contact with food or household items contaminated by the urine or feces of infected multimammate rats.
• ▪Lassa fever can spread from person to person, particularly in healthcare settings where standard infection prevention and control measures are inadequate.

NCDC response measures

• ▪The Nigeria Centre for Disease Control and Prevention deployed national rapid response teams across seven high-burden states and distributed personal protective equipment to health facilities to contain the Lassa fever outbreak.
• ▪The Nigeria Centre for Disease Control and Prevention developed a 30-day Healthcare Worker Protection Plan, supported by the World Health Organization and the US Centers for Disease Control and Prevention, to reduce infections among frontline health workers.

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