Ross River Virus Infection of Horses: Appraisal of Ecological and Clinical Consequences

Abstract

Ross River virus (RRV) is a mosquito-borne arbovirus of the genus Alphavirus that causes disease in humans and horses in Australia. A temporal association of RRV infection in horses with clinical signs including pyrexia, malaise, and polyarthralgia has been reported, along with reduced athletic performance, often for extended periods. Despite these reports, disease due to RRV remains somewhat controversial as experimental infection of horses has resulted in obvious viraemia yet minimal signs of clinical disease. The relatively high viraemia demonstrated by horses infected with RRV has led to speculation that they could act as an important reservoir host of the virus, although this remains unclear. This review sought to appraise the existing literature relating to RRV infection of horses and to summarize the ecological and clinical consequences of RRV of relevance to the equine industry and to public health more broadly.

Keywords: Alphavirus; Arbovirus; Equine; Mosquito; Ross River virus.