Media release from Nelson Marlborough DHB

Three cases of Legionellosis were notified to the Public Health Service (PHS) in Marlborough between April 22 and May 9, 2011, compared to one case last year.

Nelson Marlborough Medical Officer of Health Dr Jill Sherwood said, "All three cases were admitted to hospital and tested positive for L. pneumophila, serogroup 1 which makes up about 50% of Legionellosis cases notified in New Zealand.

"Legionellosis illness may range from a mild flu like illness to severe pneumonia with symptoms including fever, dry cough, anorexia, shortness of breath, chills, muscle aches and headaches and sometimes stomach pain and diarrhoea.

"The illness is not passed from person to person. Incubation is usually two to 10 days," said Dr Sherwood.

She advised people with concerns about their health to see their GP.

People most at risk of severe disease are those over 50 years of age, smokers, and anyone with immune suppression. Infection normally occurs after inhaling spray and mist from water containing Legionella bacteria.

She said none of the cases had the most common risk factor of compost/potting mix exposure and investigations were continuing to identify a possible common source such as a cooling tower.

Large commercial air conditioning systems that use cooling towers are potential sources of contamination as well as, hot water systems, air humidifiers and spa pools.

Businesses with cooling towers are required to have a programme in place to monitor for Legionella and treat the water in the cooling towers to ensure that no bacteria can survive. These are generally in commercial and industrial areas.

The Public Health Service has been looking at common areas that the three people had visited in the past two months and have taken samples from cooling towers in these areas.

Dr Sherwood said results of the first of these tests would be available in two weeks time.

She said cooling towers that samples had been taken from had been given further chemical treatment as a precautionary measure to eliminate any risk of infection.

Nelson Marlborough Public Health Service (NMPHS) investigates cases of legionellosis notified to the Medical Officer of Health by a doctor or a laboratory, in order to identify possible sources of Legionella bacteria and to prevent others from becoming ill. This may involve providing public health advice to individuals, agencies and organisations as required.

NMPHS does not provide direct clinical services or general water or soil testing other than in the context of investigating notified cases of disease.