Wales’ Chief Medical Officer, Dr Ruth Hussey, is asking people to follow simple steps if they have symptoms of a seasonal sickness bug.
Following a number of isolated incidents on wards across Wales, Dr Hussey is urging people to use common sense if they become unwell.
Sge said: "The sickness and diarrhoea bug, which can be caused by Norovirus in some patients, normally lasts between 24 and 60 hours, though symptoms tend to ease after two days.
"People can, in most cases, self-medicate. Take paracetamol to relieve symptoms of any fever and aches, and drink plenty of water to replace the fluids lost through diarrhoea and vomiting. This prevents dehydration.
"To reduce the risk of passing the virus onto others, wash your hands frequently and thoroughly with soap and water, particularly after using the toilet and before preparing food, and don’t share towels or flannels.
"If you think you have a seasonal diarrhoea and vomiting bug, stay at home and don't go to the doctor, because it is contagious and there is nothing the doctor can do while you have it.
"Seek advice online or by telephone from NHS Direct, or speak to a pharmacist. However, contact your GP to seek advice if your symptoms last longer than a few days or if you already have a serious illness.
"Outbreaks in busy places such as hospitals, nursing homes and schools are not uncommon because the virus can survive for several days on surfaces or objects touched by an infected person.
"To help prevent the spread of the bug hospitals may restrict visiting to affected areas. If you already have sickness or diarrhoea, please do not visit.”
If you have concerns about your health, call NHS Direct Wales on 0845 46 47 or visit the Choose Well web site. You can also download the Choose Well app.