Officials are attempting to trace the contacts of the latest person to be diagnosed with coronavirus in the UK.
The woman, who flew into London Heathrow from China a few days ago, is the ninth case to be confirmed.
She is being treated at a specialist NHS centre at Guy’s and St Thomas’ in central London and efforts are under way to find any close contacts.
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.
The new case – announced on Wednesday evening – is the first to be identified in London.
England’s chief medical officer said the patient contracted the virus in China and sources said the woman developed symptoms after landing, called NHS 111 and later tested positive.
It comes after Prof Paul Cosford, from Public Health England, told the BBC on Wednesday that more UK cases were “highly likely”.
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.
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.
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