Government staff members register residents of Shing Yu House of Tin Shing Court, where residents are subject to compulsory testing, Hong Kong, June 4, 2021. (PHOTO/HKSAR GOVERNMENT)

HONG KONG – Around 850 residents of a building in Tin Shui Wai in the New Territories were tested for COVID-19 overnight as a secondary schoolgirl who lives there tested preliminarily positive for a mutated strain of COVID-19. 

The government designated Shing Yu House of Tin Shing Court a "restriction-testing declaration" effective from 8 pm Friday, requiring residents there to stay in their premises and undergo compulsory testing.

The testing exercise ended at around 7 am Saturday and no one has tested positive for the coronavirus, the government said in a statement in the morning.

The patient visited the Hong Kong International Education Expo at the Hong Kong Convention and Exhibition Centre in Wan Chai on May 29

The government said it had provided simple food for those subject to compulsory testing, including canned food, cup noodles, corn kernels, etc. Each resident was also given a box of facial masks.

The 17-year-old student developed symptoms including fever, runny nose, headache and loss of smell on June 2 and attended Tin Shui Wai (Tin Yip Road) Community Health Centre the next day where she submitted deep throat saliva for testing, according to a press release issued by the Health Department’s Centre for Health Protection (CHP) Friday evening.

The sample tested preliminary positive and was found to carry the N501Y mutant strain, the CHP said.

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She is a student of Queen Elizabeth School Old Students' Association Tong Kwok Wah Secondary School in Tin Shui Wai and has attended tutorial class at Tak Wing Industrial Building in Tuen Mun.

She visited the Hong Kong International Education Expo at the Hong Kong Convention and Exhibition Centre in Wan Chai on May 29.

Around 2.5 million doses of COVID-19 vaccines have been administered to the public since the launch of the citywide vaccination drive in the financial hub on Feb 26

As N501Y mutant strains are highly transmissible, the CHP said it “has to carry out prudent measures on infection control, so as to stop the potential risk of spreading the virus.”

The school the patient attended and the places she had stayed during the incubation period will be included in a compulsory testing notice.

The CHP said the student and her family members have not received COVID-19 vaccination. Her family members and other close contacts were put under quarantine for 21 days.