DATE: 10 December, 2009
SUBJECT: Legionnaires’ Disease cases prompt warning about potting mix and compost
Canterbury District Health Board’s Community and Public Health division is advising gardeners to take care when opening
bags of potting mix or handling compost, following notification of five cases of Legionnaires’ Disease in the region.
Since September, the Medical Officer of Health has been notified of five cases of Legionnaires' Disease, including one
death.
Legionnaires’ Disease is a pneumonia caused by Legionella bacteria that are commonly found in water and soils, including
potting mix and compost. Potting mix was the likely source of the infection in four of the cases in Canterbury. The
person who died contracted the infection while overseas recently.
Dr Ramon Pink, Medical Officer of Health for Canterbury, said recommendations for handling and warnings were printed on
most bags of potting mix.
“Recent cases are a reminder of the potential risk of getting Legionnaires’ Disease from potting mix. It is very
important to take care to avoid inhaling the dust when opening and handling the potting mix.” “Bags should be carefully
opened in a well ventilated area, preferably outdoors, and away from the face. Dampening down the mix with gentle
watering is advised. Also make sure that you always wash your hands after handling potting mix and doing any gardening,”
Dr Pink said.
Risk factors include being over 50 years of age, having a long term illness, particularly a lung disease, being a smoker
or having low immunity. Symptoms of Legionnaires’ Disease may include dry coughing, high fever, chills, diarrhoea,
shortness of breath, chest pains, headaches, excessive sweating, nausea, vomiting, and abdominal pain.
Anyone with these symptoms who has been handling potting mix or compost recently should seek advice from their General
Practitioner.
In the past 12 months, 15 cases of Legionellosis have been notified in Canterbury.
Nationally in 2008 there were 76 cases notified, including four deaths.
ENDS