An acute hemorrhagic disorder caused by infection with the Lassa virus. It is endemic to West Africa and is associated with a mortality rate of 10-15%, rising to 25% in pregnant women.
The Lassa virus (an arenavirus) is transmitted to humans through contaminated food and household items or by contact with the urine and feces of rodents.
Up to 20% of affected individuals experience non-specific viral symptoms such as fever, facial swelling, conjunctivitis, fatigue, body aches, etc. In addition, nausea, vomiting with blood, or more severe symptoms with bleeding in any part of the body may occur.
Diagnosis is on the basis of a clinical history with emphasis on a history of travel to an endemic area.
The antiviral drug used is called ribavirin. Early initiation of treatment has been shown to have a better prognosis.
- John S Schieffelin, MD, MSPH. Lassa fever. UpToDate. Sep 14, 2016.
- Khan SH, Goba A, Chu M, et al. New opportunities for field research on the pathogenesis and treatment of Lassa fever. Antiviral Res 2008; 78:103.
- Branco LM, Grove JN, Boisen ML, et al. Emerging trends in Lassa fever: redefining the role of immunoglobulin M and inflammation in diagnosing acute infection. Virol J 2011; 8:478.
- Centers for Disease Control and Prevention. Lassa Fever: Diagnosis. https://www.cdc.gov/vhf/lassa/diagnosis/index.html
- Centers for Disease Control and Prevention. Viral Hemorrhagic Fevers (VHFs): Information for Healthcare Workers. http://www.cdc.gov/vhf/abroad/healthcare-workers.html
