The deadly mosquito-borne virus Encephalitis has been detected for the first time in parts of Australia, prompting health fears.
Australia's health chief issued a public warning after encephalitis virus was detected at sites in flood-ravaged areas of New South Wales, Victoria and South Australia.
The resurgence of Japanese encephalitis and the detection of Murray Valley encephalitis in mosquitoes has health authorities worried.
While most people with the disease can have minimal symptoms, some people develop meningitis or encephalitis with symptoms including confusion, headaches, neck stiffness, tremors, drowsiness, and seizures.
Health authorities are urging residents to wear mosquito repellent and remain vigilant.
No humans have contracted the Murray Valley variant, but it was been detected in mosquitoes during monitoring through chickens which are bred specifically to test the spread of mosquito-transmitted viruses.
"There has been a large increase of mosquito populations so far this season, making the need to protect ourselves even more important," Chief public health officer Professor Nicola Spurrier said in a statement.
It continued: "The best protection … is to not get bitten in the first place. It is important South Australians remain vigilant and take simple steps to protect themselves against mosquito bites, including wearing long-sleeved, light-coloured clothing."
There have been seven deaths from 45 cases of the Japanese variant in Australia since January 1, 2021, with almost all of the cases from 2022.
Floods which have swept across the area have exacerbated the risk and would continue as the recovery effort increased in coming weeks and months.
Waterbirds are thriving from the flooding and this is usually how mosquitoes pick up the disease before passing it on to humans.
"People are going to be travelling to the Riverland to help mop up after the floods … [and] we need to be careful", Immunisation Coalition chairman Rod Pearce said.
There is no treatment available for either virus, and a vaccine only available for the Japanese variant.