Mosquitoes near bushland and water

What they carry here

NSW Health lists the viruses that some mosquitoes transmit in New South Wales: Japanese encephalitis, Ross River, Barmah Forest, Kunjin and Murray Valley encephalitis. NSW Health’s Ross River virus factsheet names the people more likely to catch it, and the list reads like a portrait of the bush and the water’s edge: people who live or work in warm, humid places near bodies of water, people in or around wetlands or rivers, and people who camp, fish, hike or garden in coastal and inland areas.

Ross River virus

From NSW Health’s factsheet

Symptoms

Fever, chills, headache, aching, stiff or swollen joints (especially in the morning), a rash on the body, arms or legs, tiredness or weakness. Many people have no symptoms.

Timing

Usually 7 to 10 days after the bite. Most people recover fully after a few weeks; others have joint pain and tiredness for many months.

Vaccine

None at present. Not being bitten is the best way to avoid it.

Ross River virus is spread when a mosquito bites an infected animal or person and then bites someone else. It does not pass directly from person to person, and there is no specific treatment: a doctor can advise on the symptoms.

When and where to take care

In New South Wales, most mosquitoes become active at dawn and dusk and into the evening. NSW Health suggests limiting time outdoors where there are lots of mosquitoes, particularly around swamps and wetlands. Mosquitoes can bite through tight clothing, which is why its advice is loose, long-sleeved, light-coloured clothes, covered shoes and socks.

Repellent, done properly

The most effective repellents contain DEET, picaridin or oil of lemon eucalyptus, NSW Health says, and the higher the concentration, the longer the protection. How you put it on matters as much as what is in it:

1. Sunscreen first, then repellent.
2. A thin, even layer rubbed into all exposed skin. Don’t mist yourself in spots: mosquitoes find any patch left bare.
3. Keep it away from the eyes and mouth, and off open wounds, broken skin and grazes.
4. Reapply as the label says, sooner when you sweat, and after swimming.
5. For children, put it on them yourself; never let young children apply their own. Most repellents are safe from 3 months of age used as directed, but some are only for children 12 months and older, so check the label.

Wristbands, patches, ultrasonic devices and phone apps don’t give effective protection, NSW Health says, and natural repellents such as citronella, eucalyptus and tea tree oil generally give very limited protection. Every insect repellent on sale in Australia has to carry registration from the Australian Pesticides and Veterinary Medicines Authority, the body that checks products for safety and effectiveness.

A walk around the yard

Mosquitoes need water to breed. Taken together, NSW Health’s two pages give a list that works as a walk around a garden on the bush edge:

• Tip out or put away anything that holds water: buckets, tyres, toys.
• Empty and wipe out bird baths, pet water bowls and water features, once a week.
• Fill pot plant bases with sand.
• Once a week, flush the water out of plants that hold it in their leaves, bromeliads for example.
• Keep bins covered, and store anything that can hold water under cover or somewhere dry.
• Keep gutters and drains clear, so rain flows through rather than pooling.
• Make sure every opening on a rainwater tank or septic tank is covered or firmly screened.
• Keep the lawn mowed.
• Fit fly screens on windows, doors, vents and chimneys.

A neglected pool can be a haven for mosquitoes, though a properly cleaned and chlorinated one rarely is. If you use insecticide sprays around the house, NSW Health warns against using them near aquariums and fishponds, because the fish can be harmed. Insect zappers that use light have not been proven to reduce mosquito numbers and often kill harmless insects.

After a bite

Most bites can be managed by washing with soap and water or using an ice pack for pain and swelling; antihistamine creams may ease the itch. Try not to scratch, which can break the skin and lead to infection. If a bite looks infected, with swelling, pain, redness and inflammation, a pharmacist can help.