Healthy living

Diseases transmitted by mosquitoes in Western Australia

Fight the bite

In Western Australia, mosquitoes can transmit Ross River virus, Barmah Forest virus, Kunjin virus and the potentially fatal Murray Valley encephalitis and Japanese encephalitis virus. Whilst there is a vaccine for Japanese encephalitis, there is currently no cure or vaccine for any of the other diseases. The most effective way to prevent infection is to avoid being bitten.

Example of a skin rash from mosquito-borne diseases such as Ross River virus and Barmah Forest virus


Skin rashes are one of the symptoms from mosquito-borne diseases such as Ross River virus and Barmah Forest virus

Common mosquito-borne diseases

Ross River virus and Barmah Forest virus are WAs most common mosquito-borne diseases.

Symptoms include:

  • skin rashes
  • painful or swollen joints
  • sore muscles
  • flu-like symptoms (fever, chills, headache)
  • tiredness or weakness.

These symptoms can last for several weeks or even months. The only way to confirm if you have a mosquito-borne disease is by having a specific blood test. Consult your GP if you are experiencing any of these symptoms.

Skin rashes are one of the symptoms from mosquito-borne diseases such as Ross River virus and Barmah Forest virus

More serious mosquito-borne diseases

Murray Valley encephalitis and Japanese encephalitis are rare but potentially fatal diseases.

Early symptoms include:

  • fever
  • drowsiness
  • headache
  • stiff neck
  • nausea
  • dizziness.

People experiencing these symptoms should seek medical advice quickly. In severe cases, people may experience fits, lapse into a coma, be left with permanent brain damage or die.

In young children, fever might be the only early sign of disease. Parents should see their doctor if concerned, particularly if their child experiences drowsiness, floppiness, irritability, poor feeding or general distress.

Kunjin virus disease also occurs in WA. Generally, the symptoms are milder than Murray Valley and Japanese encephalitis.

Dengue, malaria and other exotic mosquito-borne diseases

Dengue, malaria and a range of other serious mosquito-borne illnesses are not transmitted in WA. However, many cases are reported each year from travellers returning to WA from overseas and interstate. If you intend to travel, research your destination and understand the health risks.

Where to get help

Last reviewed: 22-03-2022

Environmental Health


Fight the Bite is an initiative of the Government of South Australia.
This web content has been reproduced and adapted with permission from SA Health.

This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.

Fight the bite: protect yourself against disease-carrying mosquitoes. Cover up. Repel. Clean up.