Hong Kong ramps up contact tracing as Covid-19 cases decline

HONG KONG (BLOOMBERG) - Hong Kong resumed sending compulsory testing notices (CTNs) after a drop in daily infections freed up lab capacity, allowing authorities to revive the elaborate tracking and isolation system that underpinned its Covid Zero strategy.

The government issued notices for 10 premises on Tuesday (March 22), the first since the programme was put on hold in late February as surging cases overwhelmed the city's testing and tracking capacity.

Alerts are sent via the LeaveHomeSafe app - mandatory for entry to restaurants and other public venues - though health officials said they'll initially target high-risk buildings where many infections are found, like residential premises.

The resumption of CTNs is a step back toward strict Covid Zero, which Hong Kong was forced to pivot away from in recent months as the arrival of Omicron threw its health system into disarray.

The city's record outbreak sparked a raft of changes to longstanding measures: patients with mild cases no longer have to go to hospital, close contacts are largely able to isolate at home until they test negative with a rapid-antigen test, and the city's daily case tally partly relies on residents to self-report at-home positive results.

Chief Executive Carrie Lam had indicated compulsory notices were imminent on Monday when she announced the blueprint for easing of stringent social distancing measures and border curbs that had drawn criticism from the financial hub's banking and business communities.

The city's community testing centres have capacity for 100,000 to 120,000 tests each day, according to Department of Health official Albert Au.

"Since we have the resources, then we should test as many people as possible, hopefully to identify more cases and cut the transmission chains in the community," Mr Au said at a briefing on Tuesday.

A subsequent rise in daily case numbers - which have dropped to about 14,100 from a peak of more than 50,000 in early March - would mean "we are achieving our purpose," he said.

Anyone who can prove they've tested positive since Dec 31 is exempted from the compulsory testing notice, a potentially tricky criterion for some Hong Kongers to meet.

The roll out of a self-reporting website earlier this month meant some residents, concerned about the possibility of being sent to community isolation facilities, didn't declare positive results from their at-home rapid tests.