Victoria has recorded its first human case and death from the mosquito-borne Murray Valley encephalitis (MVE) since 1974, after tests revealed a woman who died earlier this month had the virus.
The woman, aged in her 60s, was from the Buloke Shire in the state's north-west, and health authorities initially thought she had contracted Japanese encephalitis.
Testing has revealed she had Murray Valley encephalitis.
Victoria's chief health officer Brett Sutton urged people to take steps to protect themselves from the virus, particularly in affected areas.
"People should continue to be vigilant and take steps to avoid mosquito bites — especially in northern Victoria, where Murray Valley encephalitis virus and other mosquito-borne diseases are known to be circulating," he said.
"Simple precautions include wearing long, loose-fitting, light-coloured clothing, using insect repellents, removing stagnant water around homes or properties, and avoiding the outdoors when mosquitoes are observed, especially at dusk and dawn."
Murray Valley encephalitis virus, Japanese encephalitis virus, and West Nile (Kunjin) virus have been detected in mosquitoes in several LGAs in northern Victoria in recent months.
Victoria has recorded one confirmed case of Japanese encephalitis this mosquito season.
According to the state's health department, most people infected with Murray Valley encephalitis virus do not have symptoms.
When they occur, symptoms may include fever, headache, nausea, vomiting and muscle aches, and in serious cases, people can develop meningitis or encephalitis.
Warning issued after detection in mosquito
On Thursday, the Swan Hill Rural City Council said routine monitoring had revealed a positive detection in a mosquito caught in the rural town of Robinvale, 470 kilometres north of Melbourne.
The health department later confirmed the positive test result.
"MVE virus continues to be detected in mosquitoes in northern Victoria this mosquito season," a spokesperson said.
"These results mean that MVE virus is circulating widely in the mosquito population and indicate a significant risk to people."
In late January, the department advised residents around Mildura, about 90kms north-west of Robinvale, that there was a very high chance of human cases developing due to growing virus detections in the region.
Swan Hill council's public health coordinator Kelsey Corrie said staff were working to control mosquito populations in Robinvale.
"Given there is no effective treatment or vaccine for MVE, preventing mosquito bites is the best protection against the virus," Ms Corrie said.
