An Epidemiological Analysis of Lassa Fever Outbreak in Nigeria from January 2019 to June 2023

Lassa Fever (LF) is an acute viral haemorrhagic zoonotic disease, is endemic in some parts of Nigeria. The disease alert and outbreak threshold are known; however, there has been a shift from the previous seasonal transmission pattern to an all year-round transmission. The aim of this study was to carry out the analysis on LF and highlight the magnitude of the disease over a five-year period. We described data on Lassa fever and highlighted the magnitude of the disease over a five-year period. We conducted a secondary data analysis of LF with specific surveillance data from the NCDC for five years period (January 2019 to June 2023). A total of 29347 suspected cases were reported within the study period; of these, 4469 were confirmed cases, 861 were dead cases by NCDC. However, highest percentage for the case fatality rate/ratio was recorded in the year 2019 with 20.9% and lowest was recorded in the year 2023 with 17.3%. The highest percentage case positive rate was recorded in the year 2023 with 18.7% and lowest was recorded in the year 2021 with 11.0%.