Descriptive analysis of Lassa fever outbreak in Taraba State, Nigeria: Epi Week 1 – 7, 2025

Introduction The Lassa virus is the cause of Lassa fever (LF). It is an endemic in some states in Nigeria. Inadequate infection prevention and control measures, increases transmission of LF. In January 2025, the index case of the outbreak was reported from Bali, Taraba State. We investigated and contained the outbreak to assess its scope, describe, and implement public health measures. Methods We defined a suspected case as “any resident of Taraba State with severe febrile illness not responsive to the usual causes of fever in the area with or without sore-throat and at least one of the following: bloody stools, vomiting blood, bleeding into the skin and unexplained bleeding from the nose, vagina or eyes” January 1, 2025. We reviewed surveillance reports and hospital records. A standardized line-listing form was developed to capture clinical and demographic information of the cases. The aim was to contain and describe the outbreak in time, place, and person. Results A total of 165 suspected cases, 70(42%) confirmed cases and 37(22.4%) deaths were recorded. Jalingo Local Government Area had the highest number of suspected cases 52(32%), Bali 35(21.2%) and Ardo-Kola LGA 20(12.1%). The highest number of confirmed cases were reported from Bali 23(33%), Ardo-Kola 15(21.4%) and Jalingo (14)20%. The majority of the cases were reported in epi week 4 and age group 15 – 24 years were the most affected with 30(43%) cases. A total of 46(66%) of all reported confirmed cases were males. Ardo-Kola had an attack rate of 10.9 per 100,000 higher than other reported LGAs. The overall case fatality rate (CFR) across the LGAs was 53%. Conclusion The LF outbreak was investigated and described. We assisted the State Ministry of Health in strengthen the LF surveillance and community sensitization. We recommended the SMOH to conduct regular training on IPC to healthcare workers.