LASSA FEVER "THE DISEASE THAT IS THREATING A WHOLE NATION''
] Outbreaks and History of Infection. Lassa fever was first recognized in 1969 in Lassa, Nigeria. Subsequent outbreaks occurred in Nigeria, Liberia, and Sierra Leone. In some parts of Sierra Leone and Liberia, 10% to 16% of all patients admitted to hospitals have Lassa fever. Some Lassa fever cases have been "imported" into the U.S. and U.K. through viremic travelers who acquired the disease elsewhere. A few notes on outbreaks: - 1969, northern Nigeria - first recognized outbreak of the disease. - 1970 to present, Liberia. Most cases were hospital workers who acquired the disease in the hospital from the index patient. - 1970 to present, Sierra Leone. It is estimated that 6% of all residents in the initial endemic area have antibodies to Lassa Fever, even though only 0.2% were recognized as clinically ill. - Estimated 100,000-300,000 infections per year in West Afric...