Lassa Fever: An Old World Arenavirus A brief summary of lassa fever, its history, pathology and effects on the indigenous populations. Also, lassa fever in the context of newly emerging diseases. LASSA FEVER On January 12, 1969, a missionary nun, working in the small town of Lassa, Nigeria, began complaining of a backache. Thinking she had merely pulled a muscle, she ignored the pain and went on about her business. After a week, however, the nurse had a throat so sore and so filled with ulcers, she couldn't swallow. Thinking she was suffering from one of the many bacterial diseases endemic to the area, her sisters administered every antibiotic they