Health officials are investigating an outbreak of Legionnaires’ disease in Carmarthen.
Three people, all with links to Carmarthen, were admitted to hospital as a result of their illness but have since been discharged.
Legionnaires’ disease is contracted by breathing in droplets from contaminated water sources. It cannot be passed from person to person.
Symptoms include breathlessness, chest pain and a dry cough, as well as fever, muscle aches, and sometimes vomiting and diarrhoea.
In an unrelated case, precautionary measures have been taken at Llandrindod Wells hospital after legionella bacteria - which can cause Legionnaires' disease - was found during routine tests on the hospital's water supply.
There are no reported cases of anyone being affected at this time, but Powys Teaching Health Board says anyone concerned should contact their GP or NHS Direct.