The Health Service Executive (HSE) has written to GPs in Sligo, Donegal and Cavan asking them to be vigilant for any potential cases of Legionnaires' disease following the discovery of the deadly bacteria in a hotel swimming pool in Co Donegal.
Visitors to the Redcastle Hotel near Moville who used the Thalasso Spa pool may have been exposed to the legionella bacteria since the pool opened last January.
The bacteria was discovered in the saltwater heated pool after the HSE opened an investigation in early July into a case of Legionnaire's disease notified a short time earlier in a Co Derry hospital.
The illness, which has a 10 per cent death rate, is contracted through inhaled water droplets and has an incubation period of two to 10 days.
An elderly priest contracted the condition, but he has since left hospital and is making a full recovery. He visited the Redcastle Hotel at the end of June.
A spokesman for the hotel said they closed the pool as soon as they were informed of water test results and it would remain closed until they got a clean bill of health from the HSE.
In a letter to GPs, sent this week, Dr Joan O'Donnell of the HSE's Health Protection Surveillance Centre said that "in light of the fact that this hotel is a busy tourist destination for people both north and south of the border and the public were exposed to this ongoing risk up to August 11, I would be grateful if you would request all clinicians in your area to be vigilant of any cases of pneumonia or possible Legionnaires disease which may be associated with travel to Donegal in the past three weeks".
After notification of the illness by the Public Health Department of the Western Area Board, Derry, the HSE inspected the hotel on July 13th, as part of investigations on both sides of the Border. Air samples were taken but the pool was not closed.
A further inspection took place two weeks later on July 27th when samples of water from the swimming pool and surrounding area were taken. The results of these samples became available on August 11th and showed contamination with the legionella bacteria.
The spokesman for the hotel said it had not been established that the man treated in hospital had contracted the disease there. "The hotel was inspected along with many other facilities where the man had been."
He said that the salt water supplying the pool was separate to the main water system at the hotel and that other samples taken elsewhere in the hotel were clear. "The pool is a part of a brand new facility, open since January. The bacteria may have been imported as part of the equipment," he said.
The hotel took advice from UK public health expert Dr William Thomas, of ISHEM Consulting, who told them the levels of legionella present in the pool "would present no risk to most healthy individuals" and "only persons with underlying respiratory or other serious pre-existing health complaints are likely to be at risk".
The spokesman also said that the incubation period of the disease had passed.
"To our knowledge no other cases have appeared," he said. "With the passage of time it is increasingly less likely that they will."
A spokeswoman for the HSE said that environmental health officers and the proprietors of the hotel are working together to address the problem.
"As the pool is closed there is no ongoing risk to human health," she said. "In an effort to identify other potential cases general practitioners and clinicians on both sides of the Border were informed. To date, no further cases associated with this premises have been identified."