It is time to be aware of legionnaires’ disease as the temptation to get into the garden grows.
There were 18 cases reported to the Southern District Health Board (SDHB) last year, two of which were in Central Otago.
Southern DHB public health physician Dr Susan Jack said although there were “usually very few” cases, if any, reported in Central Otago, there were already 14 cases reported across the wider Southern region.
Legionnaires’ disease is a severe form of pneumonia, lung inflammation usually caused by infection.
The disease cannot be caught from person-to-person contact, and most people get legionellosis after inhaling the bacteria as a dust or water aerosol.
The other main source for the infection is contaminated water systems.
She said, in New Zealand, there is usually an increase in cases each spring, which is strongly associated with the seasonal increase in gardening activity, and in particular, activity with potting mix and compost material. Potting mix and compost contain a huge variety of living micro-organisms, including legionella.
As a result, it was important people were careful in the garden.
Anyone working closely with compost or potting mix should be wearing a close-fitting face mask and gardening gloves. Dampening the compost with water before removing it from the bag can reduce the aerosol risk.
Symptoms can include coughing, shortness of breath, fever and muscle aches.
“If you have symptoms like this, you should visit your GP for assessment,” Dr Jack said.
To minimise the risk of contracting legionellosis from soil, compost or potting mix:
Water gardens and composts gently, using a low-pressure hose.
Store bags of potting mix out of direct sunlight. When stored in the sunlight, the temperature inside the bags can range from 20-40degC, making it ideal for legionella bacteria to grow.
Wear gloves when handling soil, compost or potting mix.
Open bags of composted potting mix slowly, directing the opening away from the face to avoid inhaling the mix. Avoid opening bags in enclosed areas.
When working in greenhouses, potting sheds or indoors, make sure that the working area is well ventilated.