Ross River virus (RRV) and Barmah Forest virus (BFV) are the most common mosquito-borne viruses causing human disease in Western Australia (WA). Barmah Forest virus is an RNA virus in the genus Alphavirus. Barmah Forest virus (BFV) disease can cause joint inflammation and pain, fatigue and a rash of variable appearance. What are the symptoms? People suffering from RRV or BFV diseases may experience a wide range of symptoms common to both viruses. Barmah Forest virus (BFV) is an RNA virus in the genus Alphavirus. Features of BFV disease include fever, arthralgia and rash that are clinically indistinguishable from those caused by Ross River virus disease.