Legionnaire's outbreak in Edinburgh cost NHS almost £750,000
The Legionnaires' disease outbreak in Edinburgh last year cost the health service almost £750,000.
Four people - three men and a woman - died but the cause has still not been found.
Further investigations are now being carried out to to identify the exact source of the outbreak which was mainly restricted to the south west of the city.
The report points to a "source near or in the EH11 2 postcode area".
And available data supports "the possibility that cooling towers in south-west Edinburgh could be the source".
The full scale of the costs involved have become clear for the first time with the final bill put at £725,800.
Of that £600,000 was spent treating those admitted to hospital admissions with a further £112,000 on enhanced staffing to cope with the outbreak.
Lab costs, medication and public information added to the final bill.
Edinburgh Central MSP Marco Biagi, whose constituency includes the badly affected Gorgie area, said the second interim report to NHS Lothian Board on the subject offered "a rare glimmer of light" into the probe but said people still want to know the cause.
He added: "While legionella is simple to diagnose in a person because of the body's immune response, it's much harder to detect in water samples in a lab. It therefore isn't much of a surprise to learn from the report that there were no 'smoking gun' lab results from any of the potential sources of the outbreak.
"All eyes will now be on the Health & Safety Executive to bring some closure to all those who fell ill or lived in the affected area.
"It is vital the HSE communicates more about the steps in their inquiry than they have until now. A year on from the Edinburgh outbreak, people still want answers."
Elaine Russell, of law firm Irwin Mitchell, which represents families of people who lost their lives in the tragedy, as well as many of the victims who are still suffering from longer-term symptoms, said: "There is still new information being revealed over a year after the outbreak began and our clients still have so many unanswered questions.
"It is imperative that the further investigations and full reports are completed as soon as possible to prevent ever longer delays in identifying once and for all what went wrong and why.
"There is a sense among those affected and their families that they are not being told everything and we are fighting on their behalf for information to be released.
"We have already commissioned our own experts to find the source of the outbreak as the authorities have so far just not provided enough information to those that have been affected."
In total, 92 cases were identified - 56 confirmed and 36 probable - and the 7.1% fatality rate among confirmed cases was higher than recent UK or European outbreaks.
More than 1000 patients were investigated and treated in primary care with 45 admitted to acute hospitals. A total of 22 required critical care, 19 were admitted to intensive care and three to a high dependency unit.
The report describes the impact of the outbreak on the NHS as "considerable" and concludes: "Appropriate control measures were applied quickly and work is continuing to prevent any future similar outbreaks."
It also states the "coordinated response and prompt action" by those dealing with it resulted in "fewer deaths than in previous outbreaks of similar size".
Prof Alison McCallum, director of public health and health policy at NHS Lothian, said: "It is one year since the outbreak and we understand the community's desire to move on. While elements of the investigation are ongoing, a comprehensive review of the actions taken during the outbreak has been carried out and a range of recommendations have been made."
The Crown Office is still engaged in "a highly complex ongoing investigation" and that the families of those who died during the outbreak continue to be kept updated on significant developments.