Missing pieces in cop's infection puzzle

A 35-year-old police constable has been confirmed with Covid-19 from an unknown local source, breaking the city's 38-day streak of no such cases, health authorities say.

A high viral load was found in the constable's initial deep throat saliva sample taken on Sunday but three subsequent tests taken at Queen Elizabeth Hospital came back negative, the Centre for Health Protection's head of communicable disease branch Chuang Shuk-kwan said yesterday. He also tested negative for antibodies.

Authorities have yet to explain the discrepancy but still listed the constable as a confirmed case.

"There is no chance of contamination in the laboratories, so we're treating him as an unlinked local case at the moment," Chuang said.

She said "every now and then" some confirmed cases test negative after being admitted to hospital.

"We understand test results may vary with the time and location of specimen taking and a small proportion of patients may not develop antibodies," she said.

The constable, who resides at Wai Mei House in Yau Tong's Yau Mei Court, developed a sore throat, cough and runny nose on Friday.

He had booked to get his first dose of the Sinovac vaccine from the Central Library vaccination center in Causeway Bay on the same day but was denied entry after staff noticed his symptoms.

Asked if the constable could have inhaled an inactivated virus from the Sinovac jabs in the vaccination center, Chuang said University of Hong Kong researchers were commissioned to conduct genetic sequencing on the constable's coronavirus to identify the possible source of his infection.

All officers at the Wan Chai police station were required to undergo mandatory tests by tomorrow and around 50 people, including 30 officers and two detainees escorted by the constable, were sent to quarantine.

His two children attend the SAHK Child Development Centre in Lok Fu and Lutheran Church Kwun Tong Kindergarten, both of which will be closed for two to three days for cleaning.

The constable had dined in the Tokachi Gyuu Japanese Restaurant branches at Domain mall in Yau Tong and Tin Yiu shopping center in Tin Shui Wai, the Lok Fu Place food court, Cafe de Coral in Yau Lai Shopping Centre, a Chinese restaurant on the sixth floor of police headquarters and ItaMoMo Cafe in Temple Mall in Wong Tai Sin.

People who have visited these places on the same dates as the constable will be notified and encouraged to take virus tests.

Along with six cases imported from Indonesia and Dubai, the tally yesterday rose to 11,849 cases, including 210 deaths.

Meanwhile, the LeaveHomeSafe app was updated with vaccination e-records yesterday. Secretary for Innovation and Technology Alfred Sit Wing-hang warned that using someone else's record will constitute a criminal offense.

Separately, infectious disease expert Joseph Tsang Kay-yan from the Hong Kong Medical Association called for authorities to step up the frequency of tests of those returning from Longgang district, Shenzhen, where at least 13 asymptomatic local infections have been reported since May 21.

Currently, Hong Kong permanent residents may return without quarantine under the Return2hk program as Longgang is not listed under the medium to high risk areas by the National Health Commission.

jane.cheung@singtaonewscorp.com