Background Lassa fever is an acute viral hemorrhagic zoonotic disease. The epicentre of Lassa in Nigeria is Ondo and Edo but recently, there has been an upsurge in Benue State. This is in addition to an emerging pattern of all year transmission representing a drift from peak period of November-April. In this study, we described the epidemiology of Lassa fever in Benue State from January-December 2022.

Methods We conducted a secondary analyses of Lassa fever data obtained from Surveillance outbreak response management analysis system (SORMAS), Benue State, Nigeria over a 12 month period (January-December). Data on total reported cases, tested positive, mortality and sociodemographic characteristics was extracted and analysed.

Results A total of 264 suspected cases were reported within the study period; of these, 34 (12.9%) were confirmed by laboratory diagnosis with 11 deaths and case fatality rate (CFR) of 32.4%. Of the total confirmed cases, 22 (64.7%) were male while the median age range 30–39 years had the highest number, 78 (29.5%) of confirmed cases. Majority, 29 (85.3%) of the confirmed cases within the study period occurred in Makurdi, the State capital. The seasonal trend of Lassa fever from epi-curve was propagated with peak from January to February.

Conclusion There was a very high burden and endemicity of Lassa fever in Benue State with an unprecedented highest CFR ever recorded among the 36 States of Nigeria which has become the new hotspot in the country especially Makurdi the State capital and young active working population more affected. Lassa fever transmission occurs all year-round with peak from January-February. There is need to develop preparedness plans and define thresholds for Lassa fever epidemic.