Lassa fever situation report for week 1 to week 15 from 2021 to 2023 in Nigeria: a review

Lassa fever is a viral hemorrhagic fever caused by Lassa virus. The Lassa virus is an enveloped single-stranded, non-lytic bi-segmented negative-stranded RNA virus belonging to the family Arenaviridae. Lassa fever is relatively common or endemic in West Africa or particularly in countries such as Benin, Ghana, Guinea, Liberia, Mali, Sierra Leone, and Nigeria. Humans usually become infected with the virus through exposure to food or household items contaminated with the urine or faeces of infected multimammate rat while spread of the disease between or among persons is by direct contact. The disease cases rises to the peak during the dry season particularly between December to April and falls in May annually. The incubation period for the disease is between 1 – 3 weeks, which can lead to spread from region to region. This review focuses on the secondary data for the epidemiological trend of the Lassa fever disease in Nigeria. The rodent host and reservoir is the primary driver of the Lassa fever seasonal trends. Therefore, to control the disease, it is necessary to control the rodent host by killing it. This can be achieved through the use of trap,poisoned bait and interference with their breeding by killing the newly born off springs.