The Department of Health has seen a rise in the detection of Ross River virus in the South West, including the Peel region.
The warning follows ongoing Ross River virus (RRV) detections in mosquitoes and a recent increase in the number of human cases of RRV disease notified to the Department of Health, indicating the virus is very active in the environment.
The current risk of acquiring RRV is highest in the South West of WA, and along the coastal Midwest and Gascoyne regions, from Jurien Bay to Denham.
Acting Managing Scientist at the Department of Health, Dr Abbey Potter, said the increased activity was likely to be the result of prevailing 'La Nia' weather conditions, coupled with a number of years of below average Ross River Virus activity in WA.
"RRV naturally cycles in the environment between mosquitoes and animal hosts, such as kangaroos. During an outbreak, infected animals develop immunity to the virus, reducing the potential for transmission in subsequent years," she said.
"We have now experienced a number of years of below-average activity of RRV, so it is reasonable to expect that fewer animal hosts are immune at the moment. When low herd immunity is coupled with large numbers of mosquitoes and sustained virus activity, we can expect to see an increase in the number of cases of RRV disease in people."
Symptoms of the virus can last for weeks to months, and include painful or swollen joints, sore muscles, skin rash, fever, fatigue and headaches.
The only way to diagnose the disease is by visiting your doctor and having a specific blood test.
There is currently no vaccine or specific treatment for the virus.
The only way to prevent infection is to avoid being bitten by mosquitoes.
While there is no need to alter travel plans to the South West, individuals living or traveling in the region are encouraged to take the following precautions to prevent mosquito bites:
- Avoid outdoor exposure, particularly at dawn and early evening
- Wear protective (long, loose-fitting, light-coloured) clothing when outdoors
- Apply an effective personal repellent containing diethyltoluamide (DEET) or picaridin evenly to all areas of exposed skin and always follow the label instructions
- Ensure infants and children are adequately protected against mosquito bites, preferably with suitable clothing, bed nets or other forms of insect screening
- Ensure insect screens are installed and in good condition on houses and caravans
- Remove water holding containers from around the home and garden to ensure mosquitoes do not breed in your own backyard
- Use mosquito coils and mosquito lanterns and apply barrier sprays containing bifenthrin in patio and outdoor areas around houses
- Use mosquito nets and mosquito-proof tents if sleeping outside.
Visit HealthyWA (external site) for more information about mosquito prevention.