Health New Zealand is urging Kiwi gardeners to take simple precautions this spring, after 159 hospital admissions for Legionnaires’ disease were recorded across the country in the past year.

Legionnaires’ disease is a type of pneumonia which can be caught by breathing in legionella bacteria. Legionella thrives in moist environments and stagnant water, including potting mix and compost, spas and swimming pools, hot water systems and commercial air conditioning units.

Dr Sally Thomas, Medical Officer of Health for the National Public Health Service, says Legionnaires’ disease can cause severe illness very quickly, and in some cases, it can be life threatening.

“However, the disease is preventable and does not spread from person to person.  People can take simple steps to protect themselves, and spring is an ideal time to remind gardeners how to reduce their risk.”

Health New Zealand recommends the following precautions when handling bagged or bulk potting mix or compost:

  • wear gloves and a well-fitting mask – an N95 or equivalent is best
  • open bags of potting mix away from your face
  • work in well-ventilated areas
  • dampen potting mix to reduce dust
  • wash hands thoroughly after gardening

Dr Thomas says older people, smokers, and people with chronic illnesses or weakened immune systems are more susceptible, but anyone can be affected.

Symptoms of Legionnaires’ disease include:

  • flu-like illness
  • cough and fever
  • chills and shortness of breath
  • muscle aches, headache, and diarrhoea

“If you experience these symptoms, particularly after using potting mix or compost, you should contact your usual health care provider for advice promptly or call Healthline for free on 0800 611 116.”

For more info on the risks, symptoms, and prevention of Legionnaires’ disease visit:

Legionnaires' disease (legionellosis) - Health NZ (external link)