“There are still some hidden cases in the community. Any increases in social activities may increase the spread; this also includes cross-boundary movements,” Chuang said. “If we reopen the border too early, it might lead to more transmissions.”

Chuang said the health authorities had already contacted the bar in question, which was called China Secret and located in the Lee Chau Commercial Building on Hart Avenue. The operator of the bar would arrange for staff there to undergo testing, she added.

Meanwhile, specimen bottles for testing would be distributed to more than 2,000 students and teachers at the patient’s school, which he last visited on September 29. The site would also be closed for 14 days.

Two students who had meals with the patient were considered close contacts, and would be put into quarantine.

A spokesman for the Vocational Training Council, which manages the school, said they were notified on Friday that a student from an interdisciplinary programme was confirmed to be infected with Covid-19. The student wore masks during classes.

The school would suspend operations until October 13 and step up disinfection work at the campus.

Saturday’s three other cases were imported from the Philippines, India and Britain.

The daily tally brought the city’s confirmed infection total to 5,108, with 105 related deaths. It also marked the 13th consecutive day of fewer than 20 infections.

Subdued ‘golden week’ looms for Hong Kong, as Covid-19 keeps mainlanders away

Pang Yiu-kai, chairman of the Hong Kong Tourism Board, said he believed the number of inbound travellers during the mainland National Day holidays, known as golden week, would be very low this year because of the city’s border restrictions.

Mainland holidaymakers traditionally cross into the city in droves over the National Day break, but currently all but essential workers from mainland China, Macau and Taiwan are required to spend 14 days in compulsory quarantine in a hotel or at home.

Hong Kong’s October 1-4 holiday overlaps this year with the Mid-Autumn Festival, while mainlanders get an eight-day break from National Day on October 1 that usually sees millions travelling within the country and overseas.

Pang said his organisation was in talks with the travel trade on standardising hygiene procedures for tourism services to instil more confidence in potential visitors.

Trump flown to hospital after being given experimental drug for Covid-19

He added the board would promote its domestic tourism scheme again when the pandemic eased.

Education minister Kevin Yeung Yun-hung said on Saturday that the authorities would monitor the overall epidemic situation and decide when to further relax restrictions at schools, such as resuming full-day classes and arranging for pupils living on the mainland to return to campuses in the city.

“We are actively in discussion with the mainland, especially Shenzhen, to see if some pupils … could first return to schools [in Hong Kong],” Yeung said. “But this will depend on the epidemic situation on both sides of the border.”

02:33

Millions travel as National Day opens ‘golden week’, China’s first big holiday since Covid-19

Millions travel as National Day opens ‘golden week’, China’s first big holiday since Covid-19

“There are more people going out to spend money in recent days. I believe you have to observe for a longer time first to see if there are any related outbreaks happening,” he told a radio programme on Saturday morning.

As the pandemic forced global travel to a standstill, the city’s tourism trade had earlier called on authorities to relax the public-gathering rule barring groups larger than four specifically for the sector, in order to allow operators to run local tours and earn some much-needed income.

Pointing again to the five infections of unknown origins, Hui said: “If we relax the rule further at this moment, I am worried that it could trigger an outbreak.”