The Centre for Health Protection would adjust policies against the epidemic by taking into account the risk in different countries, the department said.

“As the capacity of quarantine facilities in Hong Kong is limited at the moment, the government has decided that quarantine centres need to be reserved for close contacts of confirmed cases of Covid-19,” it said.

The city only has about 700 places left in quarantine facilities, with some reserved for the 3,400 Hongkongers to be evacuated from Hubei province, the epicentre of the outbreak, in groups.

The city on Sunday recorded seven more confirmed cases, bringing the total tally to 148. Six of the latest cases were imported.

There was already a red alert in place on South Korea, Iran, Egypt and the 26 European nations in the Schengen border-free region.

Those arriving from Iran; Daegu and Gyeongsangbuk-do in South Korea; and the Emilia-Romagna, Lombardy and Veneto regions of Italy – the worst-hit country after China – face mandatory quarantine in government camps.

It was announced earlier that from Tuesday all arrivals, including Hong Kong residents, from the 26 countries in the Schengen region, which has a combined population of more than 420 million, would be required to undergo mandatory self-quarantine for 14 days.

With Europe and the US experiencing a surge in Covid-19 cases, Hongkongers are scrambling to return home.

Elizabeth Quat, a lawmaker from the Democratic Alliance for the Betterment and Progress of Hong Kong, said many Hong Kong students in Britain had booked flights home. She said some had complained they were unable to get medical treatment after suspecting they had been infected.

“A Hong Kong student in London started coughing and has had a low-grade fever since Tuesday. Her roommates and teachers also started to show symptoms. They called private clinics for help but were rejected,” Quat said.

“Another student in Manchester suspects he has the coronavirus because he has a fever and cough. He sought help in hospital but doctors told him just to quarantine himself. He was not tested or given any medication.”

Few people in Britain were wearing masks and Quat said the student told her he felt discriminated against when he wore one in hospital.

A search on Cathay Pacific’s website on Sunday evening showed no seats were available for flights from London Heathrow airport to Hong Kong until Thursday, when a one-way ticket could be bought for about HK$6,000 (US$769).

For Cathay flights from Berlin to Hong Kong, the earliest available seats were also on Thursday, flying via London with the journey taking up to 22½ hours.

Hong Kong’s flagship airline announced on Sunday evening that because many local students and residents in North America and Britain were eager to return home as soon as possible it had added flights from New York, Boston and London. There would be also more seats on flights for the Los Angeles, Seattle and San Francisco routes.

As of Sunday evening, there were more than 80,000 infections in mainland China, where the coronavirus originated. There were more than 1,140 cases in Britain and about 2,700 in the US.

Cily Pang, who studies at the University of Münster in Germany, returned home to Hong Kong last month and had originally booked a flight back to school a week ago. She decided to stay home longer because the city was safer.

Her university is in North Rhine-Westphalia, the hardest-hit state in Germany.

“A friend of mine who studies in Britain managed to buy a ticket back to Hong Kong today,” the 28-year-old said.

She knew of other Hong Kong students in Europe who were eager to return home because the outbreak was worsening. Many people in Germany were still not wearing a mask, she added.

“Some of my friends in Europe told me they use scarves to hide their masks because they do not want to be discriminated against,” she said.

Education sector lawmaker Ip Kin-yuen urged Hong Kong students in Europe and the US to return home as soon as possible. He said that some parents have told him it had been difficult to secure a flight because the demand had soared.

But Henry Wong Yuk-chun, general manager at The Edge Learning Centre, which prepares students for university admissions in the US, said it was less likely those studying there would return to Hong Kong after the travel restrictions.

“The situation in the US is not very serious and most states have suspended classes,” Wong said. “So far I haven’t had any inquiries from parents or students about coming back because of the coronavirus.”

Wong suggested students in the US avoid travelling as much as possible and take protective measures. “I think it’s better to stay than to move,” he said.

Alice Chan Cheung Lok-yee, executive director of the Travel Industry Council, said there were at least six Hong Kong tours in Egypt, with around 100 people in total.

“They will arrive in Hong Kong by Wednesday,” she said, adding that all tours, involving at least 14 groups with around 270 travellers, had been cancelled.

There were no Hong Kong tours in Ireland or the US, according to Chan.

Chan said at least 27 tours, with about 540 travellers, currently in Europe including in Schengen countries, would not arrive in Hong Kong until Tuesday.

Meanwhile, Australian Prime Minister Scott Morrison announced that, from midnight on Sunday, all travellers entering the country had to isolate themselves for 14 days amid a rise in imported infections.

The council said at least six travel agencies had cancelled tours to Australia until mid-April. New Zealand on Saturday announced the same travel restrictions, resulting in some tours to the country being cancelled.