Semliki Forest virus (SFV) infects humans, mosquitoes, wild birds, rodents, domestic animals and primates. It belongs to the family Togaviridae genus Alphavirus and has multiple strains, some of which are virulent (such as L10, V13, and Osterrieth) and others which are avirulent (such as A8, A7, A7). SFV is enveloped and contains a single stranded RNA genome within its capsid.
SFV can cause a lethal encephalitis (swelling of the brain) in rodents, but most human infections are asymptomatic or very mild. During the initial stages of infection symptoms are indistinguishable from those of malaria or influenza.
- Joint and/or muscle aches
- Rare symptoms of abdominal pain, diarrhea, and conjunctivitis have been reported
SFV is transmitted via mosquitoes particularly Aedes species.
SFV is found throughout Africa and parts of Asia, and potentially central and southern Europe. Reports of disease are very rare.
Impact for Society – what are we doing?
Although SFV rarely causes disease, it has been used extensively in research as a viral life cycle model due to its efficient replication. Its broad host range has enabled its development as a gene therapy tool and as a vector for genes encoding vaccines and anti-cancer agents.
* Image by Dr. Fred Murphy and Sylvia Whitfield courtesy of Public Health Image Library (PHIL)