Officials are attempting to trace the contacts of the latest person to be diagnosed with coronavirus in the UK.
The woman, being treated at Guy’s and St Thomas’ in London, flew into Heathrow from China a few days ago.
England’s chief medical officer has said experts are exploring how to limit a potential epidemic in the UK to avoid an NHS crisis.
People quarantined on the Wirral after returning from the city at the centre of the outbreak are set to be released.
More than 80 people staying in accommodation at Arrowe Park Hospital will be allowed to leave after testing negative for the new strain of coronavirus.
They are one of two groups of British nationals evacuated from Wuhan, with the second quarantined near Milton Keynes.
Matt Raw, one of those quarantined on the Wirral, told BBC Breakfast that his experience was nothing like being imprisoned and that NHS staff had been “absolutely wonderful” throughout his stay.
Health Secretary Matt Hancock expressed his gratitude to those leaving Arrowe Park on Thursday and said people “can be reassured that their departure presents no risk to the public”.
The new case – announced on Wednesday evening – is the UK’s ninth and the first to be identified in London.
England’s chief medical officer, Professor Chris Whitty, said the patient contracted the virus in China and sources said the woman developed symptoms after landing, called NHS 111 and later tested positive.
‘Contain and delay’
Prof Whitty told BBC Radio 4’s Today programme it was hoped China “gets on top of the epidemic”.
But he said that containment and isolation remain the focus for medical teams – and that work was now under way to work out how to delay any potential outbreak in the UK.
He said: “We basically have a strategy which depends upon four tactical aims: the first one is to contain; the second of these is to delay; the third of these is to do the science and the research; and the fourth is to mitigate so we can brace the NHS.”
Prof Whitty added: “If we are going to get an outbreak here in the UK – and this is an if not a when – then putting it back in time, into the summer period away from the winter pressures on the NHS, buying us a bit more time to understand the virus better, possibly having some seasonal advantage, is a big advantage.”
On Wednesday, British businessman Steve Walsh, one of the nine UK cases of coronavirus, left hospital having fully recovered.
Mr Walsh, a 53-year-old scout leader from Hove in East Sussex, now posed “no risk to the public”, NHS England said.
He was the third case of the virus to be confirmed in the UK, following two Chinese nationals testing positive in York.
Mr Walsh contracted coronavirus on a business trip to Singapore and unknowingly passed it on to 11 other people – five of whom then returned to the UK.
Two of them are known to be GPs who worked at a nursing home, Worthing Hospital and two medical centres in the Brighton area.
A total of 1,750 people in the UK have tested negative for the virus, which causes the disease now known as Covid-19.
On Wednesday, there was a sharp increase in the number of new cases diagnosed in Wuhan and the surrounding province, Hubei, with a total of 60,000 infections and 1,350 deaths across China.
What are the symptoms of coronavirus and what can help stop its spread?
The main signs of infection are fever (high temperature) and a cough as well as shortness of breath and breathing difficulties.
Frequent hand washing with soap or gel, avoiding close contact with people who are ill and not touching your eyes, nose and mouth with unwashed hands, can help cut the risk of infection.
Catching coughs and sneezes in a tissue, binning it and washing your hands can minimise the risk of spreading disease.
Anyone experiencing symptoms, even if mild, after travelling from mainland China, Thailand, Japan, Republic of Korea, Hong Kong, Taiwan, Singapore, Malaysia or Macau, is advised to stay indoors and call theNHS 111 phone service.
Read more about the coronavirus
SHOULD WE WORRY? Our health correspondent explains
YOUR QUESTIONS: Can you get it more than once?
WHAT YOU CAN DO: Do masks really help?
UNDERSTANDING THE SPREAD: A visual guide to the outbreak
LIFE UNDER LOCKDOWN: A Wuhan diary
ECONOMIC IMPACT: Why much of ‘the world’s factory’ remains closed
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