Nigeria has reported a slight increase in new Lassa fever infections, with 12 confirmed cases recorded in epidemiological week 44 of 2025, compared to 11 cases reported in the previous week.
The Nigeria Centre for Disease Control and Prevention (NCDC), in its situation report released on Thursday, noted that the latest infections were detected in Ondo, Edo and Benue States, signalling continued transmission in key high-burden areas.
The NCDC said by the end of week 44, a total of 177 deaths had been documented, representing a Case Fatality Rate (CFR) of 18.3 per cent.
This figure exceeds the 16.5 per cent CFR reported during the same period in 2024. The country has so far recorded 8,463 suspected cases, 966 confirmed infections and seven probable cases across 21 states and 102 Local Government Areas.
Although the overall number of suspected and confirmed cases is lower than the cumulative numbers reported in 2024, the agency warned that transmission remains widespread, with several states continuing to report sustained activity.
Four states driving the infection
The NCDC noted that four states, Ondo, Bauchi, Edo and Taraba, accounted for 87 per cent of all confirmed infections reported in 2025.
Ondo contributed the highest proportion with 36 per cent, followed by Bauchi with 21 per cent, Edo with 17 per cent and Taraba with 13 per cent.
The predominant age group affected remains individuals aged between 21 and 30 years, although cases ranged from one to 96 years of age, with a median age of 30.
The male-to-female ratio among confirmed cases stood at 1 to 0.8.
The NCDC said no healthcare worker infection was recorded in week 44.
Ongoing response efforts
The National Lassa Fever Technical Working Group (TWG), in collaboration with national and international partners, continued wide-ranging response activities across the country.
During the reporting week, the agency strengthened its partnership with the Nigerian Medical Students’ Association (NiMSA) to advance prevention and control messaging.
It also participated in a bilateral meeting with Médecins Sans Frontières (MSF) Switzerland to explore areas of collaboration ahead of a possible surge in cases.
The period also saw the completion of multiple After Action Reviews (AARs) for the 2024/2025 outbreak season in Edo, Ondo and Ebonyi States.
In addition, the NCDC introduced S.O.A.R analysis as part of a capacity-building session on strategic planning and continued to share Lassa fever radio jingles with stakeholders for wider public awareness.
The agency also contributed to engagements around the national Lassa fever vaccine access plan and took part in the 2nd ECOWAS Lassa Fever International Conference in Côte d’Ivoire.
Further response activities included the deployment of 10 National Rapid Response Teams to affected states, the launch of the NCDC’s Infection Prevention and Control (IPC) e-learning platform, and the distribution of updated Viral Haemorrhagic Fever IPC guidelines to health facilities.
Lagos State provided thermometers to contacts for temperature monitoring, while health workers in Bauchi, Ebonyi and Benue received additional case management training supported by the World Health Organisation (WHO).
The INTEGRATE clinical trial also commenced in Ondo State with support from local and international research partners.
The agency continued to deliver essential commodities such as personal protective equipment, Ribavirin, body bags, hand sanitisers and thermometers to affected states.
It further advanced ongoing scientific work, including a quarterly follow-up and blood sampling exercise at selected treatment sites, and supported the development of a community-based One Health empowerment strategy.
Targeted community communication strategies were also developed based on recent survey findings, and additional sensitisation activities were conducted through radio and environmental health campaigns in high-burden states.
Challenges
Despite these efforts, the NCDC highlighted several challenges that continue to undermine the national response.
Topping the chart, is the late presentation of cases at health facilities, which contributes significantly to the rising fatality rate.
The agency added that poor health-seeking behaviour, driven largely by the high cost of treatment, remains a major concern.
It also noted persistent issues of poor environmental sanitation and low levels of awareness in high-burden communities.
Recommendations
To address these challenges, the NCDC urged states to intensify community engagement and health education efforts throughout the year.
It called on healthcare workers to maintain a high index of suspicion and to ensure early referral and timely initiation of treatment.
The agency also emphasised the need for continued investment in state-level capacity to detect, prevent and respond promptly to Lassa fever outbreaks.
READ ALSO: Resident doctors refute labour ministry’s claims of progress, insist strike continues
Lassa fever
Lassa fever is an acute viral haemorrhagic illness caused by the Lassa virus, which is transmitted to humans primarily through contact with food or household items contaminated by the urine or faeces of infected rats.
It can also spread from person to person through contact with bodily fluids.
The disease often begins with fever, weakness, and headache, and may progress to more severe symptoms such as bleeding, difficulty breathing, swelling, and organ failure.
Early diagnosis and prompt treatment with Ribavirin are critical for improving survival.
