The first case of coronavirus in Wales has been confirmed.
Chief Medical Officer Dr Frank Atherton said the adult patient had returned from northern Italy, where the virus was contracted.
Swansea council leader Rob Stewart said the diagnosis had a link to the city's Bishop Gore School, but there are no cases within any schools.
On Friday, a man on the Diamond Princess cruise ship became the first Briton to die of coronavirus.
Nineteen people have tested positive in the UK since the virus outbreak began in China.
Dr Atherton said the development was "not unexpected" and the patient was being treated at one of the four specialist units in England.
He said it was "inevitable" there would be more cases.
Dr Atherton said: "Our job is to prepare for a significant number of cases, for an epidemic in the UK, or a pandemic if it becomes a global issue."
He said the Welsh patient had been tested on Thursday, adding: "They developed symptoms and contacted the NHS and were assessed by colleagues from Public Health Wales."
He said: "All appropriate measures to provide care for the individual and to reduce the risk of transmission to others are being taken.
"I'd like to take this opportunity to assure the public that Wales and the whole of the UK is well prepared for these types of incidents."
He said to protect the patient's confidentiality no further details regarding the individual would be released.
Public Health Wales said it was is working hard to identify close contacts and taking all appropriate actions to reduce any risk to the public's health.
Aneurin Bevan health board also tweeted to say the Royal Gwent Hospital in Newport was open, despite false reports over coronavirus.
We are aware of an inaccurate story circulating this morning regarding the Royal Gwent Hospital and Coronavirus.We can confirm that all of our services including the Emergency Department are open and we would encourage patients who do need to use our services to attend as normal.— Aneurin Bevan University Health Board (@AneurinBevanUHB) February 28, 2020
Experts have warned of school closures and the cancellation of major sporting events, concerts and festivals in the UK in a bid to stop the spread of the virus.
England's chief medical officer, Prof Chris Whitty, said transmission of the virus between people in the UK was "just a matter of time".
He said if the outbreak intensifies, it may be necessary to close schools and stop mass gatherings of people for "quite a long period of time, probably more than two months".
The World Health Organization also warned that the outbreak had reached a "decisive point" and had "pandemic potential".
How deadly is the coronavirus?
Based on data from 44,000 patients with this coronavirus, the WHO says:
- 81% develop mild symptoms
- 14% develop severe symptoms
- 5% become critically ill
The proportion dying from the disease, which has been named Covid-19, appears low (between 1% and 2%) - but the figures are unreliable.
Thousands are still being treated but may go on to die - so the death rate could be higher. But it is also unclear how many mild cases remain unreported - so the death rate could also be lower.
To put this into context, about one billion people catch influenza every year, with between 290,000 and 650,000 deaths. The severity of flu changes every year.
The authorities here are stepping up a gear.
They are moving from just testing people who have been to the hotspots.
They are now beginning to test some patients, either in intensive care units or some GP surgeries, who have unexplained symptoms which might indicate coronavirus.
Things are shifting up a gear but the general message is that people should not panic.
Even though more cases are expected, officials insist the NHS is well prepared.
What should I do to prevent catching and spreading the virus?
To protect against infection, the NHS has advised people to wash their hands frequently with soap and water or a sanitiser gel.
It is best to catch coughs and sneezes with tissues, which should be thrown away immediately afterwards. Be sure to wash your hands after disposing of tissues.
Avoiding touching your eyes, nose and mouth with unwashed hands, and avoid close contact with people who are unwell.
The World Health Organization advises keeping at least a metre between you and other people, particularly those who are coughing, sneezing and have a fever.
What is the official advice?
The Foreign and Commonwealth Office (FCO) is warning against all but essential travel to 11 quarantined towns in Italy, two cities in South Korea and mainland China.
The Department of Health says anyone who has returned from those specified parts of Italy and South Korea, as well as Iran, since 19 February should call the NHS 111 helpline, stay indoors and avoid contact with others.
Anyone who has returned in the past 14 days from Hubei Province in China - where the FCO has warned against all travel - should do the same.
People should also call the helpline and self-isolate if they are experiencing symptoms - however mild - after returning to the UK from the following places:
- Vietnam, Cambodia, Laos, Myanmar and parts of northern Italy since 19 February
- Mainland China, Thailand, Japan, South Korea, Hong Kong, Taiwan, Singapore, Malaysia or Macau, in the past 14 days
The latest information and travel advice is available from the Department of Health and Social Care and Public Health England (PHE), the Foreign and Commonwealth Office (FCO), the Welsh Government and Public Health Wales.
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