While the virus has become endemic in many West African countries, people are usually infected when exposed to food or objects covered in insect urine or feces.
Lassa virus is known as an acute viral hemorrhagic disease that causes bleeding from the eyes, ears and mouth. The virus, which is transmitted from rodents to humans and which humans can also transmit to each other, comes from the same family as Ebola.
The virus has become endemic in a number of West African countries such as Ghana, Guinea and Liberia. In the last few years, many travelers returning from Africa to Europe and the US have contracted Lassa, but they were treated without spreading the disease to others.
Three more cases were reported in the UK in 2022 after a newborn baby tragically died from the virus in a family returning to Bedfordshire from West Africa.
The virus is on the World Health Organization's list of notorious pathogens with epidemic or pandemic potential.
The virus, which in severe cases causes internal bleeding as well as breathing problems, facial swelling, chest pain and shock, is estimated to infect more than 200,000 people each year and cause thousands of deaths.
