Lassa Fever

Lassa fever is an acute viral haemorrhagic fever (VHF) caused by Lassa virus, a member of the arenavirus family. The disease was first described in the 1950s, and the virus was identified in 1969, when two missionary nurses died from it in the town of Lassa in Nigeria.

(Image: CDC, NCID, Special Pathogens Branch)

It is known to be endemic in Guinea, Liberia, Sierra Leone, and Nigeria, and evidence of infection has been found in other neighbouring countries including Mali, Senegal and the Central African Republic.

2012 Nigeria - widespread outbreaks in 19 of 36 States 
The Federal Ministry of Health has confirmed an increase in Lassa fever cases since January 2012. As of March 22, 623 suspected cases (108 confirmed), including 70 deaths have been recorded (see more details in the WHO Report and Relief Web report).

2009: Two cases of Lassa fever were imported into the UK, one from Nigeria and one from Mali.