Inside one of Hong Kong's Covid-19 city-wide testing centers. Photo: AFP via NurPhoto/ Tommy Walker

Hong Kong has suspended face-to-face classes and activities in all kindergartens and child care centers for two weeks from Saturday after outbreaks of upper respiratory tract infections in these facilities.

About 170 outbreaks, involving some 1,900 people, have been recorded. Of these, 60% involved kindergartens and day care centers, Sophia Chan, the Secretary for Food and Health, said on Thursday.

Chan said the closures could be extended if the situation doesn’t improve. Health officials say they are monitoring the situation in primary schools, but any outbreak would be easier to manage because it would likely be confined to an individual class, rather than the whole school.

On Wednesday, the Center for Health Protection said it was investigating nine outbreaks, affecting two kindergarten-cum-child care centers, four kindergartens and three primary schools. In a child care center in Shatin, 17 boys and nine girls had developed fevers, coughs, runny noses and sore throats and sought medical attention since November 6. They were all in stable condition and one was discharged after hospitalization.

During the face-to-face class suspension, schools should remain open so that students who lack family care can go to school if necessary, the Education Bureau said. Schools should arrange for staff to be on duty to handle school affairs and parents’ enquiries, and to look after any students who may arrive at school.

Wong Ka-hing, controller of the Center for Health Protection, said people have stayed alert to infectious diseases this year due to the Covid-19 epidemic. However, the government had to strengthen its social-distancing rules again because the outbreaks of upper respiratory tract infections still happened.

Wong added that the infections were not caused by influenza viruses. He said seasonal influenza usually began in January.

The Center for Health Protection said Thursday that 23 Covid-19 cases were reported, including 16 imported cases and seven local infections, during the 24 hours on Wednesday.

Among the local patients, six had no known source. Aged between 63 and 77, they included four taxi drivers and one Rehabus driver who picked up some primary school and kindergarten students.

A 42-year-old man, who lived in Tsing Lung Tau and worked as a salesman at the Kowloon Bay International Trade & Exhibition Centre, felt ill on Monday and tested positive on Wednesday. During his incubation period, he had been to many restaurants across the city. On October 26, he attended a wedding banquet at the U-Banquet The Starview in Tsim Sha Tsui. About 200 to 300 people who joined the event will be required to take virus tests.

Chuang Shuk-kwan, director of the Communicable Disease Division at the Center for Health Protection, said the genome sequences of the Covid-19 coronavirus collected from samples between late October and this month were different from those found in the third wave between July and early October.

Chuang said the patients identified in the “staycation” cluster in Mui Wo and other cases in Tseung Kwan O, Tung Chung and Tai Po were related to the coronavirus imported from Nepal. She said the third wave of epidemic was mainly caused by imported cases from the Philippines and Kazakhstan.

A fourth wave of infections had probably begun in Hong Kong as the strain here had changed, and was similar to one in Nepal, said Ivan Hung, Clinical Professor and Assistant Dean (Admissions), Department of Medicine, Li Ka Shing Faculty of Medicine, the University of Hong Kong. Returnees in hotel quarantine could have infected others, he added.

“Recently we have confirmed that from mid-October onwards, the strain of the coronavirus has changed significantly, meaning that probably the fourth wave has already begun,” Hung said.

“We believe there may be some cross-infection between some of the newly diagnosed patients, who are staying quarantined in a hotel and they are cross-infected with people who are staying there for staycation.”

Some travelers from Nepal could have spread the virus in hotels during their 14-day quarantine period, said David Hui Shu-cheong, chairman of the Department of Medicine and Therapeutics at The Chinese University of Hong Kong. The government should investigate whether any incoming travelers had violated quarantine rules, Hui said.

Among the 31 imported cases identified between Tuesday and Wednesday, 13 people were from Nepal.

Currently, travelers from 15 high-risk countries, including India, Pakistan, Kazakhstan, the Philippines, Indonesia, South Africa and the United States are required to present a document to show they have pre-ordered hotel rooms for two weeks before they leave for Hong Kong. Such requirements will be extended to cover people coming from all foreign countries, except mainland China and Macau, from Friday.

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