The growing coronavirus epidemic is isolating China, as other countries, trying to ward off infection or contain their own smaller outbreaks, bar entry to travellers from China, and companies including Apple scale down travel and business there.

The UK announced on Saturday it had withdrawn all but essential staff from embassies and consulates in China, as authorities at home dealt with fallout from the first two cases confirmed in Britain – a student at the University of York and a visiting relative.

The university’s vice-chancellor, Charlie Jeffery, said that although he understood the diagnoses would “cause concern and anxiety”, it would not disrupt studies. “We’re working closely with the lead agency, Public Health England, and other agencies to manage this situation,” he said.

The two patients are now under quarantine in Newcastle, and the York hotel room they had been staying in has been disinfected. The university said the student is not believed to have come into contact with anyone on campus while they had symptoms.

Authorities are trying to trace people who had “close contact” with the pair – which is defined as spending at least 15 minutes within two metres of the infected person.

In total, 203 people have been tested for the disease in Britain, and only two results have been positive. The vast majority of infections and all deaths are still inside China, and concentrated in Hubei province. By Saturday, 13,968 cases and 304 deaths had been confirmed, 45 of them overnight in Hubei province. But the rapid spread of the virus beyond Chinese borders has raised fears that other countries could face large-scale outbreaks, and many governments are taking increasingly strong measures to prevent an epidemic on their territory.

On Saturday, Australia followed the US by imposing a ban on entry to most travellers from China. Canberra said citizens, residents or relatives would still be allowed in. Countries including Uzbekistan and Vietnam cancelled flights from China altogether.

Dozens of commercial carriers have cut back or halted flights to China, and several hotel chains have said they will allow cancellations by Chinese travellers. Major companies such as Google and Facebook have banned travel to the country, while international retailers such as Starbucks and Apple have shut stores.

The convoy transporting British nationals who had arrived from Wuhan to the Wirral on Friday Photograph: Cpl Tim Laurence HANDOUT/EPA

In Hong Kong, where there are strong memories of the impact of the 2003 Sars outbreak, thousands of hospital staff went on strike, demanding that authorities close the border.

Britain has not yet brought in similar bans, but precautions are being increased. Eighty-three British nationals flown out of Wuhan on Friday spent their second night of two weeks in quarantine at Arrowe Park hospital in Wirral yesterday.

The University of Derby also asked a “very small number” of students who left Wuhan before restrictions were imposed to self-isolate for 14 days. All are currently well.

A UK-wide public health campaign is to be launched on Sunday urging people to use tissues and wash their hands regularly to help stop the spread of the virus. The message will be in adverts in newspapers and on radio and online forums known to be used by Chinese nationals living here.

Cases of human-to-human transmission, which has driven the fast rise in infections inside China, have been detected in Germany, Thailand, Taiwan, France, Japan and the US.

“The real issue now for the world is what happens outside China,” Sir Jeremy Farrar, director of the Wellcome Trust, told the BBC. “What we need to look out for now is when does [it] start to spread – if it spreads – in the community or between people outside China itself. And that will be the signal that actually other countries may suffer from the same sorts of issues we see in China.”

He said the severity of any wider outbreak could lie anywhere between something like seasonal winter flu and “something akin to what we are seeing in China at the moment”.

“The uncertainty at the moment means we cannot be sure which pathway this epidemic is going to take,” Farrar added.

Quick Guide What are coronavirus symptoms and should I go to a doctor? Show What is Covid-19? Covid-19 is caused by a member of the coronavirus family that has never been encountered before. Like other coronaviruses, it has come from animals. The World Health Organization (WHO) has declared it a pandemic. What are the symptoms this coronavirus causes? According to the WHO, the most common symptoms of Covid-19 are fever, tiredness and a dry cough. Some patients may also have a runny nose, sore throat, nasal congestion and aches and pains or diarrhoea. Some people report losing their sense of taste and/or smell. About 80% of people who get Covid-19 experience a mild case – about as serious as a regular cold – and recover without needing any special treatment. About one in six people, the WHO says, become seriously ill. The elderly and people with underlying medical problems like high blood pressure, heart problems or diabetes, or chronic respiratory conditions, are at a greater risk of serious illness from Covid-19. In the UK, the National health Service (NHS) has identified the specific symptoms to look for as experiencing either: a high temperature - you feel hot to touch on your chest or back

a new continuous cough - this means you’ve started coughing repeatedly As this is viral pneumonia, antibiotics are of no use. The antiviral drugs we have against flu will not work, and there is currently no vaccine. Recovery depends on the strength of the immune system. Should I go to the doctor if I have a cough? Medical advice varies around the world - with many countries imposing travel bans and lockdowns to try and prevent the spread of the virus. In many place people are being told to stay at home rather than visit a doctor of hospital in person. Check with your local authorities. In the UK, NHS advice is that anyone with symptoms should stay at home for at least 7 days. If you live with other people, they should stay at home for at least 14 days, to avoid spreading the infection outside the home.

Modelling published in the Lancet suggested more than 75,000 people could have been infected in Wuhan a week ago, about 50 times higher than the official worldwide total of cases at the time. If the transmissibility of the disease was “similar everywhere”, the paper said, epidemics could already be “growing exponentially in multiple major cities of China with a lag time behind the Wuhan outbreak of about one to two weeks”.Inside China, quarantine rules that have put around 50 million people on lockdown are being tightened in some places.

Huanggang, the second-worst-affected city, with over 700 infections and 14 deaths, has effectively confined almost everyone to their homes. One person from each family will be allowed out to get food every two days, although there are exceptions for medical workers, sick people seeking treatment, and those staffing supermarkets and hospitals.

Elsewhere, local governments have pushed back the end of the lunar new year break; schools and universities will not resume classes this week as planned, and in some places factories have been told to delay restarting work.

People have been urged to delay weddings, particularly the large numbers planned for today, 2 February – a popular date because, written as a sequence of numbers, it is a palindrome: “02 02 2020”.

Even funerals are under pressure, with families asked to keep mourning “simple and expeditious” to avoid gatherings. Bodies of coronavirus victims are to be cremated as soon as possible.