Surge in mosquito numbers expected across Australia with wet La Niña summer

The CSIRO has warned Australians to be more vigilant about our spindliest enemies this summer with a surge in mosquito numbers expected amid La Niña weather conditions.

Southern and central Queensland have already seen the effects of widespread rain and flooding and the Bureau of Meteorology (BOM) says those conditions are here to stay.

Across Queensland this year, there have been more than 200 cases of Barmah Forest virus, and more than 770 cases of Ross River virus – both debilitating mosquito-borne diseases.

Now, the country's peak science agency has released a set of practical guidelines to reduce the risk of exposure this festive season.

CSIRO scientist Brendan Trewin said there was growing concern the un-affectionately known "barbecue stopper" mosquito could arrive in Australia.

The Asian tiger mosquito species has been identified in Italy and the United States and has a habit of constant biting – between 20 and 100 times an hour.

"There is growing concern that this mosquito will arrive and establish in Australia — it has been caught in mosquito traps at most Australian seaports and some airports," Dr Trewin said.

"It's also in the Torres Strait but so far our biosecurity and health systems have kept it out of mainland Australia."

What can you do to prevent an onslaught of mosquitoes?

Dr Trewin said it was time to clean up your house and make sure your water tank was in good order.

He said 70 per cent of mosquito larvae survive to adulthood in water tanks – so homeowners should be checking for holes in tanks, as well as sieves and gutters.

"Rainwater tanks have been installed throughout Australian cities in response to drought and water shortages, and these invasive mosquito species thrive in water tanks," Dr Trewin said.

"If you have a water tank, it's important to make sure it doesn't turn into an accidental breeding ground for mozzies."

He said peak biting hours were dusk and dawn, and people should be liberally applying repellents and burning coils in outdoor settings.

Fans, air conditioning and fly screens were also effective at keeping the insects at bay.

Why mosquitoes are more attracted to some people than others

Dr Trewin said there was mixed evidence whether mosquitoes were attracted to stinky socks, but said they did find the smell of some skin more attractive than others.

"This is likely to be a combination of blood, metabolic by-products and bacteria on the surface of the skin," he said.

"For instance, there are certain species of mosquitoes that love the smell of the bacteria in stinky socks!

"This includes the dengue fever mosquito which loves biting humans on their ankles."

Posted 8 Dec 2021