Lassa fever is a viral disease spread by rats. It mainly affects people in parts of West Africa, where there are about 300,000 cases of Lassa fever and about 5,000 deaths from it each year.

Lassa fever killed 118 people in Nigeria in the first three months of this year, the West African country's Centre for Disease Control and Prevention (NCDC) said.

The disease, which shares similarities with Ebola, requires immediate attention. British health authorities are investigating whether Lassa fever, a viral illness with symptoms similar to Ebola ...