Recent increases in the notification of Barmah Forest virus infections in New South Wales

Abstract

Infection due to Barmah Forest virus (BFV) is an emerging problem in Australia, with increased numbers of cases being reported. BFV is a mosquito-borne arbovirus from the Togaviridae family. The virus was first isolated in 1974 from the Barmah State Forest in the Murray Valley region of the Victoria–New South Wales border, and was first shown to be pathogenic to humans in 1988. Symptoms of acute human infection may include rash, arthralgia, myalgia, lethargy and fever, and are similar to symptoms caused by Ross River virus infection. However, rash is more common and florid, and joint disease is less severe, in BFV disease than in Ross River virus disease. In a study of BFV cases on the mid-north coast of New South Wales, over half of all cases reported time off work and an illness that lasted more than 6 months. BFV disease is therefore associated with a significant burden of illness and is of public health concern. This article describes trends in the notification rates for BFV disease in New South Wales since it was made notifiable in 1991.