Explained: How to avoid the deadly legionnaires disease

Australians are warned to take care doing one popular spring activity due to the risk of contracting a potentially fatal disease.

As green thumb Aussies get back to the garden for the warm Spring weather, health experts are raising red flags that some simple garden products can be deadly if handled without care.

NSW Health warned this week legionnaires disease, in which legionella bacteria enters the lungs with potentially fatal consequences, remains a threat to gardeners.

Legionella is a naturally occurring bacteria found in common soil products sold at major retailers such as mulch, potting mix, garden soil, compost, leaf litter and animal manure.

A person can be infected with Legionnaires’ disease by breathing in contaminated dust from these products.

Symptoms of legionnaires include fever, chills, a cough, shortness of breath, aching muscles, headache, tiredness, loss of appetite and diarrhoea.

Symptoms of legionnaires include fever, chills, a cough, shortness of breath, aching muscles, headache, tiredness, loss of appetite and diarrhoea. In November 2022, a Sydney woman aged in her 60s died from the disease after using potting mix

It can develop up to 10 days after exposure to the bacteria and can lead to death in rare cases.

Most people who breathe in the bacteria don’t become ill, but the risk of infection increases for the elderly, for smokers or for those with weakened immune systems.

There have been 54 cases of the disease caused by breathing in bacteria from potting mix and soil in NSW this year.

In November 2022, a Sydney woman aged in her 60s died from the disease after using potting mix.

It is believed the woman breathed in the bacteria while gardening, leading her to fall sick with a lung infection.

Queensland Health has reported 27 cases so far this year.

Bunnings director of merchandise Jen Tucker said people working in gardens or outdoors could take a number of safety precautions to minimise their risk of contracting the disease.

Major retailer Bunnings sells many of the common garden items that can contain legionella bacteria. Picture: NCA NewsWire / David Mariuz

“This includes always wearing gloves and a dust mask, wetting potting mixes, composts or mulches before handling them and thoroughly washing your hands afterwards, especially before eating or drinking,” she said.

“It’s also a good idea to store any bagged garden materials out of the sun to prevent it getting too dry.

“As with all products, we always recommend customers carefully follow the advice and instructions on the product label.”

According to Bunnings, all manufactured potting mixes and other garden matter that are composted undergo a naturally occurring heating phase which kills most bacteria like legionella and most potting mixes sold throughout Bunnings’ Australian store network are composted.

But legionella can be found in non-composted products or potting mix.

A Queensland Health spokesman said exposure could be minimised by wetting down potting mix to reduce dust, handling potting mix and compost in well-ventilated areas, wearing gloves and a class P2 dust mask when using potting mix, washing hands after handling potting mix or soil and following a manufacturers’ warnings on potting mix labels.