With the warmer weather luring people back into their gardens, WA Health is warning the community to protect themselves from a potentially deadly bacterial infection.
Health statistics show cases of Legionnaires' disease often increase at this time of the year as people start their springtime planting.
Legionnaires' disease is a severe form of pneumonia, which can occur when a person breathes in water droplets or dust contaminated with Legionella bacteria.
People risk infection from breathing in the Legionella longbeachae bacteria when using bagged potting mixes, compost, mulches, and bulk soil supplies.
The other common Legionella bacteria – Legionella pneumophila – is the one that contaminates air conditioning cooling towers, whirlpool spas, shower heads and bodies of water.
WA Health's Executive Director Environmental Health Dr Mike Lindsay said there had been 156 notifications of Legionnaires' disease attributed to exposure to garden soils and/or potting mix since the beginning of 2020.
"Of these, 97 cases required hospitalisation and sadly, two of these cases died," he said.
Dr Lindsay said the risk and severity of infection increased for older people, smokers, or those with weakened immune systems and infections were potentially fatal in up to 10 per cent of cases.
"Gardeners can take simple precautions to reduce their risk when using bagged and bulk garden soils," he said.
"This includes wearing gloves and a well-fitting disposable face mask, opening bagged potting mix carefully using scissors, keeping potting mix damp while in use, washing hands after handling potting mix and before removing masks and storing potting mix in a cool, dry place, out of the sun."
Early symptoms of Legionnaires' disease are like a severe 'flu' infection and can develop up to 10 days after exposure to the bacteria.
Symptoms can include fever, chills, aching muscles and joints, a dry cough, headache (often severe), tiredness, loss of appetite and shortness of breath.
"If you experience symptoms, see your doctor or visit your local emergency department," Dr Lindsay said.
"Early diagnosis and treatment with antibiotics will greatly improve patient outcomes."