The Centre for Health Protection today said it is following up on a positive imported COVID-19 case with a preliminary test result involving the N501Y mutant strain.

The case involves a 28-year-old woman who arrived in Hong Kong from India on April 4 and underwent quarantine at Regal Oriental Hotel from April 4 to 25.

Upon completion of quarantine, she returned to her residence at Beauty Mansion, 69-71A Kimberley Road in Tsim Sha Tsui.

She sought medical advice on April 26 at Queen Elizabeth Hospital where her COVID-19 test result was negative after a sample was collected at the hospital’s accident and emergency department.

In accordance with the requirements of compulsory testing, she underwent the 26th day testing upon arrival in Hong Kong at a community testing centre on April 30 and the result was indeterminate.

She was arranged to be admitted to the hospital for further testing on May 2. The test result was preliminary positive and she also tested positive for COVID-19 antibodies.

As the N501Y mutant strain is with high transmissibility, the centre explained that it decided to carry out prudent measures on infection control and prevention.

Given the possible transmissibility of the patient during her presence in the community from April 25 to May 2, for prudence’s sake, the centre will arrange 21 days of compulsory quarantine for asymptomatic residents of all units in the building concerned.

Symptomatic residents will be sent to the hospital for treatment.

Separately, the centre said it is continuing its follow-up on three confirmed local COVID-19 cases with test results involving the N501Y mutant strain.

It found that the people connected with the three cases had been to Citygate in Tung Chung on April 11 and that two of them had patronised Curry Lounge, a restaurant at SeaView Crescent in Tung Chung, on the same day.

The centre added that the Government will issue a compulsory testing notice to all people who had been present at the two premises on April 11.