ýÿThe Centre for Health Protection (CHP) of the Department of Health (DH) today (December 16) said that it is investigating a preliminary positive imported case of COVID-19 involving a mutant strain.

     The case involves a 36-year-old male patient who is a local cargo crew member living at Cheung Hing Building, 44-48 Pitt Street, Yau Ma Tei. He tested negative in Hong Kong on December 9 and left Hong Kong on December 11 for the United States and returned to Hong Kong on December 13 by flight CX2071 from the US. His specimen collected upon arrival in the Temporary Specimen Collection Centre at Hong Kong International Airport tested negative for COVID-19.

     The patient underwent medical surveillance and regular compulsory testing in accordance with the relevant requirements for exempted persons. According to the patient, except from buying food in the community for a short duration of time yesterday (December 15) and going to a mobile specimen collection station to collect a sample for testing, he stayed at home during the rest of the time.

     His sample collected yesterday tested preliminary positive for COVID-19. He developed symptoms on the same day with a Ct value about 25 to 29, and carried the N501Y mutant strain but was negative for the L452R and E484K strains. The patient received two doses of COVID-19 vaccination (Comirnaty) on March 22 and April 15 in Hong Kong.

     According to information from the World Health Organization, the Omicron variant possesses multiple spike protein gene mutations. Testing by the DH's Public Health Laboratory Services Branch revealed that the spike protein gene of the patient's sample involves T478K mutation. In view of the testing property of the Omicron variant, both N501Y and T478K are two of the targets to detect the Omicron variant, hence the CHP suspects at this stage that the patient carries the Omicron variant, but a whole genome sequencing still needs to be conducted to confirm whether the patient carries the Omicron variant.

     As the patient carries a mutant strain with higher transmissibility and risk of infection, the Government will make a "restriction-testing declaration" tonight for the building where the patient resided in Hong Kong (Cheung Hing Building, Yau Ma Tei). The places where he had visited in Hong Kong during the incubation period will also be included in a compulsory testing notice. Specified persons who were present at the relevant venues at specified periods need to undergo compulsory testing on the specified date. Epidemiological investigation and contact tracing of the case will continue.

     The spokesman for the CHP said, "The Government has remained vigilant and has been closely monitoring the latest scientific data on mutant strains as well as the epidemic situation of various places. The most stringent anti-epidemic measures will be implemented to prevent the mutant strain from entering the local community."

     ýÿAt the moment, the adverse impact on the epidemic situation caused by the newly emerged mutant strains is not fully known yet, but vaccination is still essential to prevent severe cases and deaths from COVID-19 infection. The Government has launched the COVID-19 Vaccination Programme. Members of the public are encouraged to get vaccinated. Details of the programme can be found at the designated website (www.covidvaccine.gov.hk).

Ends/Thursday, December 16, 2021
Issued at HKT 19:35

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