Lassa Fever (LF) Outbreaks in Nigeria: Time for Positive and Sustained Action.

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, beginning from the early dry season months of November until the beginning of the rainy season.
  • Between 1969 and 2007, LF was reported in only 2 states (Borno and Plateau). However, from 2008 to 2012, the disease spread to an additional 8 other states; from 2013 until 2019, at least 23 states report Lassa Fever cases annually.
  • Over the 50-year period of Nigeria reporting 16,783 suspected Lassa Fever cases, 11,195 (67%) were reported between 2016 and January 29, 2020, while 632 (60%) of 1,047 Lassa fever deaths were reported during the same period.
  • In 2016, 921 suspected cases were reported. The respective figures for 2017 and 2018 were 1,030 and 3498 suspected cases. An alarm was raised over the tripling of the number of suspected cases between 2017 and 2018, only for the reported number of suspected cases to rise in 2019 to 5057 which was 145% of the reported 2018 figures.
  • During the period 1969 to 1975, the range of Lassa Fever mortality in hospitalized patients, was 33%-100%. In recent years, the mortality rate has dropped to 20%
  • Laboratory confirmation of suspected cases has been of great concern. Of the 3498 suspected cases in 2018, only 633 (18%) were confirmed LF positive, while in 2019, only 833 (16.5%) of the 5057 suspected were confirmed. Read more