The Nigeria Centre for Disease Control and Prevention has reported a renewed increase in confirmed Lassa fever infections after a brief decline, with cumulative cases rising to 963 and deaths reaching 229 in 2026.

This is according to the agency’s latest Lassa Fever Situation Report released on Friday.

Confirmed cases fell from 31 in epidemiological week 26 to 14 in week 27 before climbing to 25 in week 28, signalling continued transmission across affected states.

The NCDC said the latest infections were reported in Ondo, Bauchi, Edo, Kogi and Cross River states during week 28, while cases recorded in week 27 came from Ondo, Edo, Benue, Bauchi and Kogi states.

The agency noted that Nigeria had recorded 963 confirmed cases and 229 deaths as of week 28, resulting in a case fatality rate (CFR) of 23.8%.

According to the report, the fatality rate remains significantly higher than the 18.7% recorded during the corresponding period in 2025.

“For week 27, the country recorded 936 confirmed cases and 224 deaths, representing a case fatality rate of 23.9%, also higher than the 18.9% reported during the corresponding period in 2025,” the report stated.

The NCDC added that 23 states have reported at least one confirmed case of Lassa fever this year, with the disease spreading across 113 local government areas in week 27 and increasing to 114 local government areas by week 28.

The agency said the majority of infections remain concentrated in five states — Bauchi, Ondo, Taraba, Benue and Edo — which accounted for 85% of confirmed cases in week 27 and 86% in week 28.

It also noted that individuals aged between 21 and 30 years continue to be the most affected demographic, underscoring the disease’s impact on young adults.

The report further revealed that while no healthcare worker was infected in week 27, one healthcare worker contracted the disease in week 28.

To curb the spread of the disease, the NCDC called for sustained surveillance, early detection of cases, prompt treatment, strict adherence to infection prevention and control measures, and increased public awareness campaigns.

Lassa fever remains one of Nigeria’s most persistent public health challenges, with recurring outbreaks recorded annually across several states.

As of October 2025, the NCDC reported 172 deaths from Lassa fever across 21 states, with the case fatality rate rising to 18.6%, compared with 17% during the same period in 2024.

At the time, Ondo, Bauchi, Edo, Taraba and Ebonyi states accounted for 90% of confirmed infections, while Ondo State alone represented 35% of cases.

Confirmed infections in epidemiological week 40 increased from four cases in the previous week to 13 cases, all recorded in Ondo State.

The agency also reported that most infections occurred among people aged 21 to 30 years, with a male-to-female ratio of 1:0.8, while no healthcare worker infections were recorded during that reporting period.