One man dead and 15 in a critical condition after an outbreak of Legionnaire's disease Samples have been taken from these four facilities but Legionella is a difficult bacterium to identify and it may take up to 10 days before results of the samples are available. Dr Duncan McCormick, NHS Lothian's consultant in public health medicine and chair of the board's incident management team, said: "I would like to express my sincere condolences to the family of the patient that died. Investigations into the possible source of this outbreak are ongoing. I would like to reassure the public that household water supplies are safe and that Legionnaires' disease cannot be contracted by drinking water. Older people, particularly men, heavy smokers and those with other health conditions are at greater risk of contracting the disease. I would urge anyone who develops symptoms of Legionnaires' disease to contact NHS 24 or their GP. The Health Secretary Nicola Sturgeon will chair a meeting of the Scottish Government's Resilience Committee this morning, where she will be updated on the situation and on efforts to identify the source. The health board said the patient who died was in his 50s and had underlying health conditions. Thirteen men and two women aged between 33 and 74 are in a critical condition with the disease and are being treated in intensive care in hospitals in the Lothian area. One man has recovered and has been discharged. A further 10 men and five women are also being treated in hospitals but their illness has not yet been confirmed The first case was identified on May 28 but the disease's symptoms can begin at any time from two to 14 days after exposure to the Legionella bacteria. The bacteria are commonly found in sources of water, such as rivers and lakes. However, they can also be found in artificial water supply systems, including air conditioning systems, water services and cooling towers. The infection is contracted by breathing in small droplets of contaminated water. Symptoms include mild headaches, muscle pain, fever, a persistent cough and sometimes vomiting and diarrhoea. About half of those with Legionnaires' disease will also experience changes to their mental state, such as confusion. The condition is not contagious and cannot be spread directly from person to person. Prof Hugh Pennington, one of Britain's leading bacteriology experts, told BBC Scotland: "I don't think people should be too concerned. We've still got a relatively small number of cases. It's probably going for a particular vulnerable section of the community - men with lungs that are already damaged by other diseases and so on - and it is a fairly straightforward disease to diagnose once you know that it is a possibility.