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HealthInfo Canterbury

Avoid Legionnaires' disease by using potting mix safely

A gardener's bare hands in potting mix.Legionnaires' disease is a severe infectious disease that can give you a high fever and pneumonia (chest infection), making you very sick. It is caused by a bacteria that lives well in warm, moist conditions, and is spread by inhalation of infected droplets or particles.

In Canterbury especially, Legionnaires' disease is very common, and is usually caused by people accidentally inhaling dust from contaminated potting mix or compost when they are gardening. In 2010, Canterbury had 62 recorded cases of Legionnaires' disease and 70% of these people were sick enough to be admitted to hospital.

Anyone can get Legionnaires' disease, but if you are over 50, a smoker, have a long-term illness (especially lung disease), or have low immunity, then you may be more vulnerable to catching it, and the effects may be more serious for you.

Symptoms may include:

If you have any of these symptoms, and you have recently been handling potting mix or compost, see your general practice team as soon as possible. Make sure you tell your doctor that you have been in contact with these products. There is a special test to find out if you have Legionnaires' disease.

Safe use of potting mix

To avoid getting Legionnaires' disease, be very careful when using potting mix, seed raising mix, compost, or other soil products. It's very important that you do not inhale the dust from any of these products.

To keep yourself safe, follow these guidelines:

Written by HealthInfo clinical advisers. Endorsed by community respiratory physician, Canterbury DHB. Last reviewed May 2017.

Page reference: 39842

Review key: HILEG-49708