Murray valley encephalitis surfaces after 37 years

By Dr. Ananya Mandal, MDFeb 22 2011

A fatal and severe form of mosquito borne viral brain infection has been detected in the Riverina Murray region of New South Wales. Murray Valley encephalitis has affected sentinel chicken flocks in the northern Victorian towns of Mildura, Robinvale, Kerang and Barmah as well in the New South Wales town of Tooleybuc, near Swan Hill. The virus has not been diagnosed in a Victorian for 37 years said Victoria’s Chief Health Officer Dr John Carnie. He said although the virus had not been detected in a human, Victorians living along the Murray River should avoid being bitten by mosquitoes.

Residents are being warned, said Public Health Officer Tracey Oakman. Oakman added that the disease is transmitted by the bite of a common mosquito and can lead to permanent brain damage, or be fatal in severe cases. The symptoms of the infection include severe headaches, fever, vomiting and neck stiffness. Anyone with symptoms should seek medical attention quickly.

The Murrumbidgee Local Health Network is urging people to avoid being outside during the peak mosquito times of dawn and dusk. NSW Health Protection acting director Dr Michael Staff says it is a reminder for all people to cover up and avoid mosquito bites. He said, “While Murray Valley Encephalitis or MVE is rare, and most people will not develop symptoms, it is still a serious mosquito-borne disease that can lead to permanent brain damage and may be fatal in severe cases.” Officers advise when outdoors people should wear long, loose-fitting clothes and use insect repellent containing picaridin or DEET and ensure door and window screens were in good repair.