The health board has issued a reminder to not visit loved ones in hospital if you yourself are unwell.
Powys Teaching Health Board has said that respiratory and gastric-related infections are currently circulating.
It advises that anyone with flu or gastroenteritis - or who has been in contact with other people who have these symptoms - avoids visiting loved ones in hospital to limit the spread of infection.
Mererid Bowley, Executive Director of Public Health at Powys Teaching Health Board said: “It is important that we do everything we can to prevent infectious illnesses from being passed onto vulnerable patients and the staff caring for them.
“For most of us coughs, colds and stomach bugs can make us feel unwell for a few days. However, for those who are in hospital or a care setting and are already vulnerable, these viruses could potentially be much more serious.”
Please do not visit any hospital sites if you; feel unwell; have flu-like symptoms or a respiratory infection (e.g. COVID-19); currently have, or had, diarrhoea and/or vomiting in the past 48 hours; or have been in contact with anyone with these symptoms in the past 48 hours.
“Waiting until you feel completely better, especially ensuring it's been 48 hours since you last symptoms of sickness and/or diarrhoea, will help protect your loved ones and prevent the spread of illness,” added Ms Bowley.
“When visiting someone in hospital please follow the guidance relating to infection control provided in these spaces or ask staff if you are unsure.”