Health officials urge Kiwis to beware of bacteria in potting mix and compost

Warmer weather and daylight saving bring many Kiwis out into the garden. However, it’s also unfortunately the time when gardeners are most at risk of catching Legionnaires’ disease from bags or bulk loads of potting mix and compost.

With 108 cases of the disease already confirmed across the country this year, Health New Zealand | Te Whatu Ora is urging gardeners to take care.

“Bagged potting mix and compost can contain Legionella bacteria, which when breathed in, can cause Legionnaires’ disease” says Dr Cheryl Brunton, Medical Officer of Health for the National Public Health Service. “This disease is a type of pneumonia, which can be severe and in some cases life threatening.”

Across the country, there is typically a spike in cases of Legionnaires’ disease in spring that can be associated with increased gardening activity and warmer weather.

Dr Brunton says there are some simple actions gardeners should take to avoid getting Legionnaires’ disease:

• Work with potting mix or compost in a well-ventilated outdoor area
• Wear a well-fitting face mask. An N95 or respirator is best
• Wear gloves when handling potting mix or compost
• Open potting mix or compost bags carefully using scissors and open them away from your face
• Reduce dust by dampening down the potting mix or compost before using it
• Wash your hands thoroughly after handling potting mix or compost and before touching your face or removing your mask.

“Legionnaires’ disease is a very serious illness and following these simple steps can be lifesaving,” says Dr Brunton.

The illness may be mild but can sometimes be fatal. It is more common in older people, particularly if they smoke, have poor immunity or a chronic illness. However, even healthy young people have died from Legionella pneumonia.

Symptoms can include a ‘flu-like’ illness, with a dry cough, high fever, chills, shortness of breath, muscle aches, headaches, and diarrhoea. If you have these symptoms, you should contact your health care provider right away for advice and let them know you have been handling potting mix or compost.