This undated photo shows residential buildings in Tin Shui Wai, Hong Kong. (PHOTO/HKSAR GOVERNMENT)

HONG KONG – Hong Kong government cordoned off a building in the New Territories on Friday night for targeted testing after a preliminary positive import-related COVID-19 case involving a mutant strain was detected there.

The government set up a restricted area at around 7 pm at Block 2, Grandeur Terrace, No 88 Tin Shui Road, Tin Shui Wai and required residents there to undergo testing before 1 am Saturday. It aims at finishing the exercise at around 7 am Saturday.

The CHP said the patient tested positive to the N501Y and T478K mutant strains, meaning that she may carry the Omicron variant

In a statement, the Centre for Health Protection said the case involved a 30-year-old resident, who is a ground crew member at Hong Kong International Airport. She tested negative in 10 tests from Nov 24 to Dec 28. She developed a cough on Dec 28 and her specimen collected on Dec 30 tested preliminarily positive with a Ct value about 29 to 33, the CHP said.

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The center said the patient tested positive to the N501Y and T478K mutant strains, meaning that she may carry the Omicron variant. She has received two doses of Sinovac vaccine in Hong Kong, the center added.

“A preliminary investigation revealed that she mainly worked at the Orange Zone of HKIA to receive outbound and transit passengers, and she has likely acquired the infection during work,” according to the CHP. She has no recent travel history and she last went to work on Dec 29.

The places where she had visited and worked in Hong Kong during the incubation period will also be included in a compulsory testing notice, the CHP said.

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