Legionnaires’ Disease in Sydney prompts public health alert
Officials with NSW Health issued a public health alert due to a cluster of 5 patients with Legionella pneumophila serogroup 1 infection, with symptom onsets between 30 March and 4 April. All visited Sydney central business district (CBD) during their incubation periods. No single source for the cases has been identified, and it is possible that they are unrelated.
An investigation of a potential source in the area is underway.
Legionnaires’ disease is an uncommon infection of the lungs (pneumonia) caused by Legionella bacteria (Legionella pneumophila-found in water and Legionella longbeachae- found in soil or potting mix.)
Infection occurs 2-10 days after a person breathes in the bacteria in contaminated water vapors or dust.
Legionnaires' disease usually causes fever, chills, cough and shortness of breath. Some people also have muscle aches, headache, tiredness, loss of appetite and diarrhoea. People can become very sick with pneumonia; most people recover but the disease is occasionally fatal.
Legionnaires' disease most often affects middle-aged and older people, particularly those who smoke or who have chronic lung disease. Also at increased risk are people whose immune systems are suppressed by medications or diseases such as cancer, kidney failure, diabetes or HIV.
How is it prevented?
Legionella pneumophila bacteria can grow to high numbers in warm, stagnant water. Outbreaks are sometimes associated with contaminated cooling towers (that are part of air conditioning systems in large buildings). Regular inspections, disinfection and maintenance of cooling towers and plumbing systems limits the growth of the bacteria.
Legionella longbeachae is common in the soil and potting mix. Reduce exposure to potting mix dust by following the manufacturers' warnings on potting mix labels when gardening, including:
Wet down the potting mix to reduce the dust
Wear gloves and a mask (if possible a P2/N95 mask) when using potting mix
Wash your hands after handling potting mix or soil, and before eating, drinking or smoking.
Clinicians are advised to have a high index of suspicion for people presenting with features of pneumonia. Collect a legionella urinary antigen and sputum culture.