Two unlinked cases can now trigger block mass testingTop News | 30 Dec 2020
Thousands of residents in dozens of buildings with unrelated infections in two or more units over the past two weeks will be subject to mandatory Covid-19 tests, health authorities say. It will be followed by checks on the sewage of the blocks to make sure the virus has been eradicated.
This came as three residents in two flats at Fung Chak House, in the public estate Choi Wan (II), tested preliminary positive after mandatory tests imposed on residents of the building, where a University of Hong Kong team found sewage containing the virus.
Undersecretary for food and health Chui Tak-yi announced the tightening of the threshold triggering mandatory tests on an entire building - from four cases to two - to flush out unknown sources and silent spreaders.
Chuang Shuk-kwan, head of the communicable disease branch of the Centre for Health Protection, said if both infected flats from the same building are found to be linked to previously confirmed cases, mandatory tests will not be triggered.
"But if one of the two infected units have an unknown-source patient, all residents and visitors will have to take the test," she said.
Health authorities will trace the records on buildings fulfilling the requirement over the past two weeks and issue mandatory test notices accordingly.
"We are still counting how many blocks will be affected but there could be several dozens of them," she said.
Chuang said the three preliminary positive patients from Fung Chak came from two flats vertically apart by two floors.
In the unit with two patients, one developed a fever on Thursday and the other patient had cough on Friday. But they only went to a community test center on Monday. The third patient began coughing on Monday and took the test the same day.
Wing Shui House from Sha Tin's Lek Yuen Estate yesterday recorded a confirmed case in a fourth unit, while at Lam Shek House in Ngau Tau Kok's Ping Shek Estate a third flat had an infection. Both buildings will be added to the mandatory test list.
Undersecretary for environment Tse Chin-wan said sewage testing arranged jointly by HKU, the Environmental Protection Department and the Drainage Services Department is focusing on post-mandatory test buildings to make sure virus carriers there have all been picked up.
"If a public housing building has a confirmed case, the Housing Department will check the pipes to that unit to see if there are alterations or leakage, so they can make rectifications immediately," he said.
Chuang said Hong Kong yesterday had 53 confirmed cases - 23 males and 30 females - aged six months to 86 years old.
Three were imported - two arrivals from South Africa who flew on Qatar Airways QR818 on December 16 and one Indonesian helper arriving on December 11 on Cathay Pacific CX796, whose incubation period was longer than the typical 14 days.
The helper completed a 14-day quarantine at a Causeway Bay hotel on Thursday. On Friday she went to a Mong Kok clinic for a checkup before going to a Tseung Kwan O employment agency. She stayed at Winland 800 Hotel in Tsing Yi until she tested positive after a test at a community center on Sunday.
Chuang said genetic sequencing on imported cases found eight returnees from Britain infected with the new variant believed to be 70 percent more infectious. All UK flights have been banned since December 22.
Among 50 local cases, 14 were from unknown sources.
Local infections linked to previous cases included one more nurse from United Christian Hospital's palliative care ward 2D, taking the cluster's total to 12 patients and eight staff.
Hong Kong's tally was at 8,325 cases, including 143 deaths. More than 40 preliminary positive cases await confirmation.