Lassa Fever (LF) Outbreaks in Nigeria: Time for Positive and Sustained Action. Nigeria should declare Lassa Fever disease a public health event of national emergency and concern. Since Lassa Fever was first reported in Nigeria, in January 1969, a total of 16,783 suspected cases have been reported with 1,047 deaths. Of the fatal cases, 73 healthcare workers (doctors, nurses and other categories of hospital staff) have died. The disease occurs throughout the year, with seasonal peaks,...