Nigeria has recorded a steady rise in Lassa fever cases and deaths in the first weeks of 2026, according to the Nigeria Centre for Disease Control and Prevention (NCDC).
In its latest situation report, the NCDC said Lassa fever activity increased steadily between epidemiological weeks 1 and 3 of 2026, with rising numbers of suspected and confirmed cases as well as additional fatalities.
Data from the report showed that in Week 1 of 2026, Nigeria recorded 104 suspected Lassa fever cases, of which 21 were confirmed, and nine deaths
By Week 2, the number of confirmed cases rose to 33, while suspected cases increased to 144.
The upward trend continued in Week 3, with 157 new suspected cases reported nationwide. During the same week, 39 new confirmed cases were recorded, alongside six additional deaths.
The NCDC said the increase from 33 confirmed cases in epidemiological Week 2 to 39 in Week 3 reflects intensifying Lassa fever activity across several states.
Read also: Four things to know about Nipah virus in 2026
Confirmed cases were reported in Bauchi, Taraba, Plateau, Ondo, Edo, Ebonyi, Benue and Nasarawa states.
Cumulatively, as at Week 3 of 2026, Nigeria has recorded 17 deaths from Lassa fever, with a case fatality rate (CFR) of 18.1%.
The agency noted that this is marginally lower than the CFR of 18.2% recorded during the same period in 2025.
In total, nine states have recorded at least one confirmed case of Lassa fever in 2026, spanning 28 local government areas.
The NCDC reported that the burden of confirmed cases remains heavily concentrated in a small number of states, as 89% of all confirmed Lassa fever cases were reported from four states: Bauchi, Ondo, Taraba and Edo. The remaining 11% were reported from five other states with confirmed infections.
A further breakdown showed that Bauchi State accounted for 46% of confirmed cases nationwide, followed by Ondo State with 20%, Taraba State with 12$, and Edo State with%.
According to the agency, the predominant age group affected by Lassa fever in 2026 is 21 to 30 years. The ages of confirmed cases range from one year to 74 years, with a median age of 27.5 years.
The NCDC said the rising figures highlight the importance of sustained vigilance, early detection and preventive actions, including improved hygiene practices, rodent control, prompt health-seeking behaviour, and strict infection prevention and control measures in healthcare facilities.
Lassa fever is an acute viral haemorrhagic illness endemic in Nigeria, with outbreaks typically occurring during the dry season.
