Lassa fever found in England. Three confirmed cases of Lassa fever were reported in a family in a region in England in early February, with one death, a newborn. The family had traveled to West Africa, where the disease is endemic in several countries. Imported cases of Lassa fever are rare; these are the first reported cases in England in 13 years. Lassa fever is a rodent-borne, hemorrhagic viral illness, often referred to as a cousin of Ebola, and can be transmitted through infected body fluids. Eighty percent of infected people will have no or mild symptoms but about 20% will develop severe symptoms. The overall mortality rate is only 1%; however, in those with severe disease it climbs to more than 15%. Currently a Phase IIb clinical trial of a vaccine for Lassa fever is underway in Liberia, Nigeria, and Sierra Leone.