UK Health officials on Friday said that two people had tested positive for the novel coronavirus, in Britain's first cases since the deadly outbreak emerged in China and spread globally.
The announcement came as 83 British citizens arrived back on a UK government-chartered flight from Wuhan, the Chinese city at the centre of the epidemic which has so far killed 213 people.
The plane carrying the Britons and 27 other foreign nationals landed at the Brize Norton military airbase in south central England shortly after 1:30pm (1330 GMT).
EU citizens on board will continue on to Spain while British families disembarking were set to be isolated for 14 days at a medical facility in the country's northwest.
With a growing number of cases reported in at least 19 other countries, the World Health Organization on Thursday declared an international public health emergency.
Chris Whitty, Chief Medical Officer for England, insisted the country was "extremely well-prepared" and that officials were working with the WHO and others "to ensure we are ready for all eventualities".
"We can confirm that two patients in England, who are members of the same family, have tested positive for coronavirus," he said in a statement.
Whitty added the patients were receiving specialist care, including "tried and tested infection control procedures to prevent further spread of the virus".
He added officials were working to identify any contacts the two patients had.
AFP understands the pair had travelled to China recently. UK Health Officials declined to reveal the location, citing patient confidentiality.
The domestic Press Association news agency reported they were being treated at a hospital in Newcastle, northeast England.
Other media reports said they had been staying at a hotel in the northern county of Yorkshire when they fell ill.
"It is not surprising that we now have two confirmed cases in the UK as we live in a global world," said Devi Sridhar, Professor of Global Public Health at the University of Edinburgh.
"This is still primarily a Chinese emergency as 99 percent of cases have been in China and all deaths have been in China," he added.
British diplomatic staff had been "working round the clock" to organise Friday's airlift, and had expected to evacuate up to 200 people but only 110 boarded.
"We will work with our international partners on further assistance for those who remain," a spokesman for Prime Minister Boris Johnson said.
The British families arriving at the Royal Air Force's Brize Norton base will be ferried by bus for the two-week quarantine at Arrowe Park Hospital in The Wirral in northwest England.
They will stay in accommodation usually used by health service staff, and will have access to the internet.
Anyone with suspicious symptoms will be taken to the nearby Royal Liverpool and Broadgreen Hospital, which has a high-level infectious diseases unit.
"It's welcome news that our evacuation flight has now left Wuhan," Foreign Secretary Dominic Raab said in a statement.
"We know how distressing the situation has been for those waiting to leave."
