Scotland’s health officials are trying to pinpoint the source of the worst outbreak of Legionnaires’ disease in the country since the early 1980s.
Sixteen cooling towers at four sites in southwest Edinburgh are the focus of the investigation. There are 24 confirmed and 27 suspected cases of the disease in the Scottish capital, with 14 people in intensive care, Health Secretary Nicola Sturgeon said today. A 56-year-old man died this week while undergoing treatment.
“The key message is that the risk to public health is low, nevertheless there are a significant number of cases,” Sturgeon told the Scottish Parliament. “All appropriate action is being taken to minimize the risk of further infection.”
The airborne bacteria are contracted by inhaling small drops of contaminated water and cases often involve cooling vents in air conditioning and heating systems in buildings or showers at places such as public swimming pools. The U.K.’s worst case in recent years was at a leisure facility in Barrow-in-Furness in northwest England in 2002, when seven people died and 180 people were infected, according to the Health and Safety Executive.
The 16 towers in Lothian were cleaned with chemicals on June 3 and June 4 and more tests are taking place while the source remains uncertain, Sturgeon said. More people are likely to be infected in Edinburgh this week as the outbreak unfolds, she said at a press conference yesterday.
NHS Lothian, the public health authority for the Edinburgh area, dealt with eight new cases yesterday. Most of the cases involve men over the age of 50 with underlying health conditions, officials said. There was an increase of three confirmed cases overnight.
“All of the affected patients have links to this particular area where the cooling towers are,” Sturgeon said yesterday. It may be difficult to pinpoint the exact source of the outbreak beyond any reasonable doubt, she said.
Legionnaires’ disease isn’t contagious so it can’t be passed from person to person, officials said.
The first case in the Edinburgh outbreak was identified on May 28. The disease initially causes flu-like symptoms such as high fever and muscle pain. Once the bacteria infect the lungs, they can cause a persistent cough and intestinal problems leading to diarrhea and nausea. Treatment is with antibiotics and two of the people who were in a serious condition have since been discharged, Sturgeon said yesterday.
A probable mortality rate is 10 percent to 15 percent of those diagnosed, Jim McMenamin, a consultant epidemiologist at Health Protection Scotland, said yesterday.
“The greatest risk is among those people with chronic medical conditions and who smoke and perhaps also have a large alcohol consumption,” he said.