Concerns have been raised as a result of the discovery of a new virus
On February 11, one of the three people diagnosed with Lassa fever in the UK died. Travel to West African countries has been linked to the cases.
The virus that causes Lassa fever was discovered in 1969 in Lassa, Nigeria. The fever is primarily found in West African countries such as Sierra Leone, Liberia, Guinea, and Nigeria, where it is endemic.
It can also spread, though rarely if a person contacts an infected person’s bodily fluids or mucous membranes such as the eyes, nose, or mouth. In healthcare settings, person-to-person transmission is more common.
Symptoms usually appear 1 to 3 weeks after exposure. Mild symptoms include a slight fever, fatigue, weakness, and headache, while severe symptoms include bleeding, difficulty breathing, vomiting, facial swelling, pain in the chest, back, and abdomen, and shock.
According to the European Centre for Disease Prevention and Control, approximately 80% of cases are asymptomatic and thus go undiagnosed. An estimated 100,000 to 300,000 Lassa fever infections occur each year, with about 5,000 deaths.