ABSTRACT
Lassa fever is a zoonotic disease caused by the Lassa virus, which belongs to the Arenavirus family. The disease’s symptoms are haemorrhage, vomiting, chest pain, abdominal pain, and sometimes death. In Nigeria, the fatality ratio was 18.1% at week 8 (21–27 February 2022), lower than 22.8% in the same period in 2021. The transmission mode of Lassa fever is mainly faecal–oral, through contact with rodent excreta and other body fluids and inhalation of the aerosolised virus, and consumption of rodent meat. Person-to-person transmission can also occur through exposure to infected blood, saliva and semen, skin-to-skin contact, and contaminated objects, especially in clinical settings. The peak season of outbreaks is usually in the dry season, with a lower incidence rate during the season of rainfall. Diagnosis is through reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) to avoid confusion with other viral diseases with similar characteristics, and treatment consists of quarantining any suspected case to contain the disease and the drug Ribavirin. Prevention is through environmental and personal hygiene, vector control, and the use of personal protective equipment to avoid nosocomial infections. Measures have been put in place to contain the virus through coordination, case management, infection prevention and control (IPC), surveillance, clinical management, and increased laboratory capacity. Lassa fever infection has social consequences like stigmatisation and sensorineural hearing loss. Therefore, a major tool for preventing and controlling Lassa fever in Nigeria is to constantly create awareness about the virus and continuously educate the people in high-risk areas about ways to reduce rodent populations in their homes.
