Over the Easter long weekend every year, many Australians head out on camping trips or up to Queensland to make the most of the warm weather.
This year, they are being advised to take precautions against the Ross River virus as cases surge in the Sunshine State, with more than 1,500 detected since January.
Here's what you need to know about the virus — and what you can do to protect yourself.
What is Ross River virus?
Ross River virus, also known as epidemic polyarthritis, is an infection spread to humans by infected .
It is the most common in Australia. It is not spread directly from person to person.
Many people infected with the virus never get symptoms, but others will experience painful, swollen joints and muscle and tendon pain.
Other symptoms can include fever, headache, fatigue, a raised red rash, and swollen lymph nodes.
Some adults recover within a few weeks, while others will experience symptoms for months.
A small number will still have symptoms after a year.
Where are Ross River virus cases rising?
Ross River virus infection is considered endemic to many parts of the country — but is most common in tropical areas of Queensland, the Northern Territory, and Western Australia.
In February, Queensland Health issued a warning of a heightened risk of infection.
Surveillance detected a high number of mosquitoes carrying the virus across nine different local government areas stretching from Mackay down to south-east Queensland.
Queensland Chief Health Officer Dr John Gerrard said the infections typically rise with the onset of rain and warm temperatures in December, before peaking in February and March.
"It is also typical to see a significant number of Ross River virus cases every three to four years, so we are on track for a spike in cases," he said.
"Given high mosquito numbers combined with these latest surveillance results, we know there is a heightened risk of human exposure to mosquitoes carrying this virus right across Queensland."
There have been fever recorded since January 2024, according to Queensland Health.
In 2023, there were 699 cases of Ross River virus infection recorded across the state.
NSW has so far recorded 125 cases this year, while there have been eight in Victoria.
How can you protect yourself from Ross River virus?
There is no vaccine for Ross River virus infection, but there are several measures you can take to help protect yourself.
Gerrard recommended staying vigilant of mosquitoes, particularly at dusk and dawn when some species are most active.
"Measures to prevent mosquito bites include regularly applying insect repellent containing DEET, picardin or oil of lemon eucalyptus and wearing loose, light-coloured clothing to cover up arms, legs and feet," he said.
"Around your home, you should empty containers holding water or remove standing water, wherever possible, at least weekly and ensure flyscreens are in good order so mosquitoes can’t enter your home easily."
You can also use insecticide sprays, vapour dispensing units and mosquito coils to clear out and repel mosquitoes, and sleep under a mosquito net for extra protection overnight.
