The Centre for Health Protection said it is investigating one additional imported COVID-19 case involving the L452R mutant strain.

The case concerns a 21-year-old woman who arrived from India. She tested positive upon arrival at the airport.

Separately, the centre continues to follow up on the three imported cases involving local cargo crew who carry the L452R mutant strain.

The latest whole genome sequencing analysis revealed that the genetic sequence of case number 12387 is almost identical to that of case numbers 12376 and 12378. It showed that the three cases are very likely to have acquired the infection during their hotel stay in Germany.

Regarding the cluster of two cases with the Delta strain sub-lineage AY.4.2 with identical genetic sequences on the 15th floor of the North Wing of Four Points by Sheraton Hong Kong Tung Chung, the centre collected 73 environmental samples on November 12 from the rooms and common areas on the same floor.

Among the 73 samples, 13 tested positive for SARS-CoV-2, all of which were from the rooms involving the two cases. While another eight samples tested indeterminate, the remaining 52 samples tested negative.

Disinfection in the hotel has been completed. The centre has transferred a total of 44 guests who had stayed in the hotel from November 1 to 6, on the floor concerned, to the Penny's Bay Quarantine Centre to undergo compulsory quarantine.

Additionally, since the two preliminary positive imported COVID-19 cases had stayed in Hong Kong during the incubation period, 29 places have been included in a compulsory testing notice.

Additional testing is also required for people who have been to four other places during the specified period, due to their connection to three previous imported cases who had stayed in the city during the incubation period.

People have to follow the compulsory testing requirement above even if they have completed a COVID-19 vaccination course, the Government noted.

Meanwhile, given an outbreak of upper respiratory tract infection and/or influenza-like illness in five schools, these schools or their specified levels have also been covered in the compulsory testing notice for the sake of prudence. Those who have been fully vaccinated, however, can be exempted.

To provide free testing service for citizens subject to compulsory testing, the Government will set up mobile specimen collection trucks in Kwai Tsing and Sha Tin districts, as well as mobile specimen collection stations at the amphitheatre, Hing Man Estate in Chai Wan; the podium playground of New Jade Garden in Chai Wan; the carpark of Ocean Court in Aberdeen; the open area outside G/F, King Tai Court in San Po Kong; and Hong Kong Disneyland Park’s staff carpark.

A total of 40 cases were reported in Hong Kong in the past 14 days, all of which are imported.

For information and health advice on COVID-19, visit the Government's dedicated webpage.