People walk past Chinese New Year decorations at a market to celebrate the Lunar New Year in Hong Kong, Jan 31, 2022. (VINCENT YU / AP)

HONG KONG - Hong Kong recorded 129 new COVID-19 cases on Tuesday as health authorities raced against time to determine the sources of infection of 98 unlinked cases.

In a press briefing on Tuesday afternoon, Chuang Shuk-kwan, head of the Centre for Health Protection’s communicable disease branch, said the city had 22 new untraceable cases, the highest since the 5th  wave of infections began last month. 

Chuang Shuk-kwan, head of the Centre for Health Protection’s communicable disease branch, said the city had 22 new untraceable cases, the highest since the 5th  wave of infections began last month

“I think the number of 22 unlinked cases is highest so far since the 5th wave. Unlinked cases indicate that there are a lot of other cases that are unknown to us at the moment,” Chuang said. 

Together with the 22 new unlinked cases, the city has a total of 98 infections with unknown sources, she added.  

Of the 129 new cases on Tuesday, 102 were local infections while 27 were imported, including 10 that involved passengers of a flight that arrived on Jan 25.     

Among the local infections, 81 were suspected Omicron cases, 10 were suspected Delta infections, while 12 cases are still being investigated.

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There were two new cases that involved airport employees--a toilet cleaner and one in charge of maintaining order--who might have been infected by the passengers who arrived on Jan 25.

“Although they had full PPE (personal protective equipment) on, there were many cases who arrived in Hong Kong on the same flight. Their viral load was very high,” Chuang said, adding that the two patients could have been infected while removing their PPEs after work. 

Chuang also said that there were two new cases detected at Yat Kwai House and one case in Ying Kwai House at Kwai Chung Estate. 

She said this was to be expected even after the lockdown was lifted since the CHP had not ruled out the possibility of sporadic cases sprouting up.  

“It is still acceptable because it is not a major outbreak,” she said.

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Chuang said the Omicron variant is currently the main coronavirus mutant strain in Hong Kong, with Delta cases being detected in Wong Tai Sin and nearby areas.

“In Wong Tai Sin and Yau Tong, there are also suspected Delta variant cases so we suspect the source of infection to be in Lam Tin because we see some cases in Tseung Kwan O as well,” she said.