In this Aug 11, 2021 photo, a woman wearing a face mask walks past a flight information board at Hong Kong International Airport. (ISAAC LAWRENCE / AFP)

HONG KONG – Hong Kong detected its fifth Omicron infection on Friday as the city reported four new COVID-19 infections, bringing the overall tally to 12482.

In a statement, the Centre for Health Protection said the Omicron case involved a 37-year-old man who was confirmed to be infected with COVID-19 on Thursday. He traveled to Hong Kong from the United States on Cathay Pacific flight CX881 on Dec 7 and tested positive during the "test-and-hold" arrangement upon arrival at Hong Kong International Airport.

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“The patient had received two doses of COVID-19 vaccination (Comirnaty) in Hong Kong on June 2 and June 25. He had been asymptomatic,” the CHP said.

A spokesman for the Centre for Health Protection said there has not been a spread of the Omicron variant in the community as the five cases were all detected at the Hong Kong International Airport restricted area or at a designated quarantine hotel

Including the latest addition, there are so far five cases involving Omicron in Hong Kong, including two related to South Africa and two to Nigeria.

A spokesman for the CHP said there has not been a spread of the Omicron variant in the community as the five cases were all detected at the Hong Kong International Airport restricted area or at a designated quarantine hotel.

“The CHP will adopt the most stringent prevention and control measures to prevent the mutant strain from entering the local community,” the spokesman said.

The four new COVID-19 reported on Friday were all imported and involved two men and two women, aged 15 to 57. “Three of the cases involved mutant strains while the mutation test result of the remaining case is pending,” the CHP said.

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Three of them traveled from Vietnam — a Group B (medium-risk) place — while the remaining patient flew into Hong Kong from the United Kingdom, which is on the government’s Group A (high-risk) travel list.

A total of 61 cases have been reported in the past 14 days and all of them are imported cases.

In another development, three passengers on Cathay Pacific flight (CX764) from Ho Chi Minh City tested positive upon arrival in Hong Kong on Dec 8. The Department of Health, therefore, invoked the Prevention and Control of Disease (Regulation of Cross-boundary Conveyances and Travellers) Regulation (Cap 599H) to prohibit the landing of passenger flights from Ho Chi Minh City operated by Cathay Pacific in Hong Kong from Dec 10 to 23, the CHP said.