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.

Known outbreaks/cases in 2009:

• February- March 2009:  increase in case numbers in Nigeria (Federal Capital Territory, Ondo and Edo states)