Swimming fears as 'brain-eating' bug takes over popular Aussie waterways: 'Very real threat'

Two swimming spots in WA have already been closed to swimmers after the deadly pathogen was detected.

As millions of Aussies sweat through another scorching summer, there's a rare but fatal threat emerging in the West. At least two popular swimming spots were found to harbour a deadly "brain-eating" bug forcing swimmers out of the water — and it's a "very real threat" across the nation, one expert told Yahoo News Australia.

Concerns were raised after naegleria fowleri — a deadly amoeba, which thrives in heat — was detected in Brunswick Pool — a freshwater swimming spot in WA's southwest — during a routine water quality test. And 100km south of Perth in the Shire of Waroona, swimmers have been warned to avoid Drakesbrook Weir as it too was at risk of being contaminated.

Rising temperatures and the current heatwave are to blame for the emergence of the amoeba, which is commonly known as the "brain-eating amoeba". Inhaling bacteria can cause a rare infection known as amoebic meningitis — and in most cases is fatal.

Drakesbrook Weir in Shire of Waroona, WA
Drakesbrook Weir, 100km south of Perth, is the latest swimming spot to close over fears it contains the deadly 'brain-eating amoeba' known as naegleria fowleri. Source: Google Images

"It’s a horrible, horrible thing and it's a very real threat in lots of areas [across Australia]," water researcher Professor Ian Wright told Yahoo News Australia. He said while it's "really, really rare" the "consequences are terrible".

"You could probably have a thousand people swim in that waterway and not get it. But if you get infected, it's likely fatal. It takes between one and 18 days to die".

Accidentally swallowing the water is often fine, according to the Western Sydney University professor, but inhaling the pathogen is problematic.

"It has a really strange pathology. There's some kind of a barrier between the nose, nasal cavity and the brain, and the amoeba can get through," he said. "So just never put your head underwater. Avoid getting water up your nose. That seems like a stupid thing to say, but it's really sensible advice."

Concerns grow as temperatures rise

Extreme conditions have blanketed WA this summer with The Shire of Waroona president Mike Walmsley admitting, "it feels like the hottest summer we've had for some time," the ABC reported.

WA Health Department water scientist Richard Theobold said a growing number of freshwater pools might harbour deadly naturally occurring amoebas as the climate got hotter — and nothing can be done to avoid it, but Aussies can be aware.

"As the temperatures rise, you'll find that natural water bodies will increase in temperature … so, more areas that are nice and warm and fresh, it's more likely you'll get Naegleria and Naegleria fowleri," he said, according to the ABC.

Warning sign at Drakesbrook Weir in WA over Amoeba fears.
It's feared the deadly bacteria could start to pop up across the country as temperatures rise. Source: ABC/Mike Walmsley

Signs have been erected at a number of swimming spots across the state warning visitors to stay out of the water — but it's a nationwide problem. Wright warns against swimming in freshwater pools, lakes, rivers or dams across the country.

"This is a really big problem right across inland Australia. It can get really hot away from the coast," he said. "Putting your head underwater is an act of faith in water quality. I will only swim in well-managed,well-treated, chlorinated pools, not freshwater spots".

Australia is getting hotter

2023 was the hottest year on record, with global temperatures rising close to 1.5 degrees above pre-industrial records. Temperatures last year were substantially worse than 2016 which previously held the title as the warmest year.

Dr. Simon Bradshaw told Yahoo News Australia, that we would expect 2024 to end up hotter than 2023 as the year after an El Niño has developed will usually be the hottest. Last year it was predicted that western Sydney would soon be the "hottest place on earth".

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