Infectious diseases

Infectious diseases are caused by microorganisms such as viruses, bacteria, fungi or parasites and can spread between individuals. In Australia they are generally not life-threatening, but they can cause serious discomfort and illness, depending on the disease. Some common infectious diseases include Ross River Virus and Legionella Infection.

Ross River Virus

Ross River Virus (RRV) is common throughout Australia, especially around inland waterways and coastal regions. RRV is spread by mosquitoes and is the most common mosquito-borne disease in Western Australia.

How can I prevent infection?

To reduce the chance of mosquito bites and potential RRV infection, follow these steps:

  • Ensure you’ve applied insect repellent prior to entering a mosquito-prone area and regularly reapply in line with the manufacturer’s instructions;
  • Avoid mosquito-prone areas, especially at dawn and dusk, when mosquitoes are more active;
  • Wear loose-fitting, light coloured clothing. Mosquitoes can bite through tight-fitting clothes and they’re attracted to the dark and dark colours;
  • Ensure you have properly fitted fly screens installed on your windows and doors; and
  • Eliminate any occurrences of stagnant water or quantities of water around your property.

Insect repellent

The most effective insect repellents are in lotion form and contain either diethyl toluamide (DEET) at between five and 20% (50 - 200g/litre) or Picaridin. Certain natural or organic repellents may provide some protection, but they are generally not as effective as DEET or Picaridin.

What are the symptoms?

The symptoms can include joint inflammation and pain, fatigue, muscle ache and rashes. Symptoms can appear anywhere between three days and three weeks after being infected. Although recovery can take several months, some people have reported intermittent symptoms for up to several years.

If you’ve developed any of the above symptoms, your doctor can confirm whether you have RRV by a blood test.


The treatment for RRV includes bed rest and pain relief medication. However, you should speak with your doctor or other medical provider for specific, professional advice.

Visit the Department of Health's website for more detailed information about RRV.

Legionella infection

Legionella bacteria are responsible for most cases of Legionnaire's disease and thrive in warm, damp environments. Although commonly spread through air conditioning ducts and water systems, the bacteria are also widely present in potting mixes, mulches, composts and garden soils. They can cause serious illness in humans if inhaled or transferred from hand to mouth. Infection can result in a type of pneumonia and include symptoms such as fever, chills, cough, aching muscles, headache, tiredness, loss of appetite and diarrhoea.

How can I prevent infection?

To help prevent infection follow these precautions when handling potting mixes, mulches, composts and garden soils:

  • Always wear gloves;
  • Keep the mix damp while in use;
  • Avoid inhaling the mix; and
  • Wash your hands thoroughly after use.

Visit the Department of Health's website for more detailed information about legionella.