People walk past Christmas-themed lights during Boxing Day in Hong Kong's Central district on Dec 26, 2021. (BERTHA WANG / AFP)

HONG KONG – Hong Kong reported six new imported COVID-19 cases on Tuesday, including five suspected Omicron infections.

The six new cases included a 39-year-old man and 16-year-old boy from the US, a 61-year-old man from the UK, a 51-year-old Pakistani male, and two Cathay Pacific aircrew members who returned from the US, Chuang Shuk-kwan, head of the Centre for Health Protection’s communicable disease branch, said at a briefing.

Due to the increasing number of aircrew members testing positive for the virus, health officials decided to tighten their quarantine rules, requiring them to undergo quarantine for three days in a designated hotel instead of staying at home

“Gene sequencing will be performed for confirmation (of Omicron infection),” Chuang said.

She added that there were 14 preliminarily positive cases, including another male aircrew member who had flown to Chicago before coming back to Hong Kong on Dec 25.

With some of the new infections with Omicron detected among aircrew, health officials decided to tighten the quarantine rules for them. Aircrew members had only been required to quarantine at home, unlike most other people returning to the city, who have to quarantine in hotels.

The new measures require that returning air cargo crew spend three days in hotel quarantine before a period of home isolation. Most recent infections of air crew staff have been discovered in the first three days.

"We expect most cases in the future to be of the new Omicron variant," said Edwin Tsui Lok-kin, controller of the CHP. "We have a very high community outbreak risk. A single spark can start a fifth wave."

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Chuang said the one of the aircrew members suspected of having the Omicron variant is a 45-year-old man who flew to New York on Dec 21 and returned to Hong Kong on Dec 24.  

He tested negative at the airport and so he was allowed to go home to his flat at One South Lane, No.1 South Lane, Shek Tong Tsui, which was cordoned off overnight on Monday evening for targeted testing but no new infection was found.  

On Dec 25, the patient went shopping in the morning before taking bus 962 to Tuen Mun to have lunch with his friend, the aircrew member who tested preliminarily positive on Tuesday.

The patient took bus 961 to go home and then went to a community testing center the following day. On Dec 27, he bought a meal from a Malay cuisine restaurant in the Western District and brought it home.  

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“We suspect he might have been infected during his stay in New York,” Chuang said.

The other aircrew member suspected of being infected with the Omicron variant lives at Peninsula Village Twilight Court, Discovery Bay.

The 46-year-old patient flew to New York on Dec 23 and came back to Hong Kong on Christmas Day. He also tested negative at the airport and mostly stayed at home, except for the two instances when he had himself tested at two community testing centers. 

The Hong Kong government on Tuesday further tightened inbound travel restrictions in light of the growing threats of Omicron. In a statement, the government announced that Brunei Darussalam and Paraguay will be listed as Group A specified (high-risk) places from Friday.

“Non-Hong Kong residents who have stayed in such regions within 21 days will not be allowed to enter the city,” the government said. The announcement came after Omicron infections were detected in the two places.

Hong Kong residents who have stayed in these places can only board a flight for Hong Kong if they have been fully vaccinated and hold a recognized COVID-19 jab record.

Upon arrival, they must undergo 21 days of compulsory quarantine in a designated quarantine hotel, during which six virus tests have to be conducted. On the 26th day of arrival in Hong Kong, they must also undergo another compulsory test in a community testing center.

With Reuters inputs