Lassa fever is caused by the Lassa virus and is primarily transmitted through the excrement of rodents and the blood and bodily fluids of patients. It is mainly prevalent in West African countries and was named after the town of Lassa in northeastern Nigeria, where the first case was discovered in 1969.
Nigeria is the main country affected by this disease, with outbreaks concentrated during the dry season from January to April. In 2020, the outbreak resulted in the death of 161 people. The incubation period of the virus is 6 to 21 days, and the onset of symptoms is slow. Symptoms include general discomfort, fever, sore throat, cough, nausea, vomiting, diarrhea, muscle pain, and chest and abdominal pain. The mortality rate for hospitalized patients is approximately 15%, but in epidemic areas, it can reach as high as 25%.
Currently, there is no available vaccine for Lassa fever, so individual protective measures are mainly taken. Family members and healthcare workers are advised to avoid contact with the blood, bodily fluids, and excrement of patients. The key to prevention is rodent control, including eliminating and protecting against rats, and personal protective measures.
