Probe into Legionnaires' cases in Greater Glasgow and Clyde
Three confirmed cases of Legionnaires' Disease are being investigated by health authorities in the NHS Greater Glasgow and Clyde area.
A public health consultant said the rise in the number of cases so close together was unusual.
The health board is checking if there is any common source for the infection.
All three people have been treated at different hospitals - two have been discharged after recovering and a third was said to be stable in hospital.
The health board is carrying out investigations in liaison with local authorities, the Health and Safety Executive and Health Protection Scotland.
Consultant in public health Dr Gillian Penrice said: "There are always a small number of cases of Legionnaires' Disease in the community every year, however this rise in the number of cases so close together is unusual.
"As a result we have begun an investigation to examine if there is any potential common source or whether these cases are coincidental, albeit unusual."
She added: "It is important to remember that Legionella cannot be spread from person to person. It is an uncommon bacterial infection."
"Legionella bacteria is sometimes found in water and can be spread through aerosols produced from water, such as air conditioning and showers and it cannot be contracted by drinking contaminated water."
The symptoms and signs include headache, fever, dry cough, breathing difficulties, stomach pains and diarrhoea. Anyone with these symptoms was urged to contact NHS 24 or their own GP.