EVE Man 08-046 Mair v2:Layout 1

Ross River virus is an arthropod-borne virus (arbovirus) and the cause of the most common mosquito-borne human disease in Australia, being frequently associated with a debilitating polyarthritis. Serological evidence would indicate that subclinical infections with the virus are widespread in horses in many areas of the country. Clinical disease can occur in horses, with affected animals displaying any or all of the following signs: pyrexia, inappetence, lameness, stiffness, swollen joints, reluctance to move, ataxia, mild colic and poor performance. Persistence of certain clinical signs such as limb soreness and impaired performance for months or even years has also been reported in a small percentage of cases. The horse is considered a possible amplifying host for the virus, with the ability to develop a high-titred viraemia and infect various mosquito species.