Residents line up to get tested for the coronavirus in Hong Kong, Jan 23, 2022. (KIN CHEUNG / AP)

HONG KONG - Hong Kong recorded 109 new COVID-19 cases on Monday, including 69 that were detected in the Kwai Chung Estate.

Chuang Shuk-kwan, head of the communicable disease branch of the Centre for Health Protection, said in a media briefing that there were 11 imported cases and 98 local infections, including five cases of unknown origin.

The cases of unknown origin involved a 13-year-old student from Tung Chung, a 53 year-old woman in Kwai Fong with a suspected Omicron infection, a 49-year-old hair salon employee in Sham Shui Po, and a 75-year-old man in Wong Tai Sin

She said  24 infections were linked to previous cases while the rest were from Kwai Chung Estate, including 27 from Yat Kwai House, 33 from Ying Kwai House, and nine cases from the other buildings at the estate.

“As for Kwai Chung Estate as of this morning, including positive and preliminary psoitive cases, there were about 210 cases so we saw an increase, and we expect more cases to come in,” Chuang said.

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Chuang said the cases of unknown origin involved a 13-year-old student from Tung Chung, a 53 year-old woman in Kwai Fong with a suspected Omicron infection, a 49-year-old hair salon employee in Sham Shui Po, and a 75-year-old man in Wong Tai Sin.

The other confirmed cases involved eight construction workers and two staff members at the Labor Department office in Cheung Sha Wan.

Chuang said traces of the Omicron and Delta variants were found in sewage samples in Wong Tai Sin. 

“Some samples carry the Delta strain and not so many Omicron. We suspect there is a silent transmission chain in the neighborhood. Residents should stay vigilant and get tested,” she said.

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She added that there were around 100 preliminary positive cases as of late Monday afternoon.