HONG KONG (BLOOMBERG) - Hong Kong's onerous system of hotel quarantine for travellers was meant to stop infection from seeping into a largely Covid-19-free city.
Instead, it has become a spreading ground, seeding an Omicron variant outbreak that has led to thousands of people being locked down and calls for reform of the controversial set-up.
An outbreak at a public housing estate of more than 200 confirmed and preliminarily positive cases on Monday (Jan 24) has been traced to a traveller who caught the Omicron variant while undergoing 21 days of isolation at a hotel in Kowloon.
While she entered the hotel coronavirus free, the pathogen was transmitted to her from an infected person staying at the same hotel.
It is at least the fourth time in a year that hotels have passed infection on instead of containing them.
The severity of this particular outbreak is escalating backlash against a travel policy that is both costly and chaotic, with travellers scrambling to secure rooms that can go for as much as US$770 (S$1,000) a night amid constantly-changing rules.
"We see those quarantine hotels as a big concern," said virologist Jin Dong-Yan at the University of Hong Kong.
"During these waves, we've learned that letting people isolate in their home might actually be a better choice."
The cramped and poorly-ventilated nature of most hotels, with travellers grouped together regardless of where they're coming from and when they entered the city, has helped the virus defy quarantine lengths of up to three weeks, one of the longest in the world.
The recent cross-infection at the Silka Seaview Hotel occurred as the city faced a surge in Omicron variant cases from returning travellers after the Christmas break, said Dr Leung Chi-chiu, former chairman of the Hong Kong Medical Association's advisory committee on communicable diseases.
These travellers were not properly grouped "into adjacent rooms by date of entry to prevent infection of persons at the end of their quarantine by newcomers," Dr Leung said.
The use of hotels for quarantine has been problematic in several countries, with the facilities also found to have spread infection in Australia and Singapore.
But those places have now pivoted to living with the virus, with vaccinated travellers allowed to isolate at home if necessary.
Most do not have to isolate after they test negative.
Hong Kong has continued to hew to a zero-tolerance approach along with mainland China, a strategy that has required increasingly aggressive measures as the virus mutates to become more transmissible.
With the emergence of Omicron, the former British colony has culled hamsters, put young children and senior government officials in quarantine camp and banned flights from eight places to slow its spread.
Late last year, Omicron was transmitted across the hallway of a quarantine hotel from an infected person to someone else when their doors were opened for testing and food collection.
In November, a patient with the Delta-plus variant likely got it from someone in the adjacent hotel room, said government experts.
Earlier in August, a domestic helper was infected by someone in the room across the hallway from hers and she tested positive only after completing the isolation period.
This caused the authorities to increase the mandated length of quarantine at the time.
But the latest Silka Seaview infection has shown the futility of moves to raise the isolation period when people can become infected at any point in their hotel stay.
To be sure, the hotel quarantine has stopped many more imported infections than it has seeded, said Dr Lam Ching-choi, a member of Hong Kong leader Carrie Lam's advisory Executive Council.
"There's always a risk, but generally speaking, the system has been effective for thousands of people for more than a year," he said.
But at a time when most of the world is shifting towards living with the virus amid high vaccination rates, the quarantine system also reflects how Hong Kong is stuck in time: The financial hub is back in the near-lockdown conditions of the pandemic's initial phase, with schools, gyms and bars shut.
Its travel bans have also meant that hundreds of residents can't return to the city, including high-ranking bank executives
Business groups have warned that Covid-Zero policy is diminishing the city's status as a global hub.
The current set of social distancing policies, set to last until early February, are unlikely to be lifted in the near-term given the growing infection numbers, said experts.
The Omicron outbreak has had the effect of lifting Hong Kong's abysmal vaccination rates, especially among the reluctant elderly.
Those with a first dose jumped to 60 per cent among those aged 60 and above, from just 51 per cent in mid-December, though the improved number is still far lower than in most developed economies.
"We have to increase the vaccination rate," said Professor Jin.
"It's impossible for us to stay with Covid-Zero forever, because Hong Kong is a very international city. If we cut links with outside world, it will be dead or half-dead."