HONG KONG: Hong Kong's leader, Carrie Lam, has said she is "deeply sorry and anxious" about the lengthy wait for residents to get tested or enter isolation facilities after a record number of new coronavirus cases left authorities scrambling.

Hong Kong's daily COVID-19 infections nearly doubled to a record 1,161 cases on Wednesday as the global financial hub battles a rapid surge that could pose the biggest test yet of its "dynamic zero" policy.

Writing on her official Facebook page on Wednesday night, Lam said that the government was working hard to enhance capacity and that the fast-spreading infections, hitting places like elderly care homes, were the last thing she wanted to see.

"I firmly believe that all people treasure our frontline medical staff, look forward to resuming their normal daily lives, and want to help Hong Kong ride out the pandemic," she said.

Hong Kong has reported close to 4,000 infections over the past two weeks, up from just two in December, taking its tally to more than 17,000 since the outbreak began in 2020, with 215 deaths, although the figures are lower than other major cities in the world.

Authorities have responded with the toughest measures since the start of the pandemic, which are taking an increasing social and economic toll on the city's 7.5 million residents.

Hong Kong has stuck to the strategy employed by mainland China to suppress all coronavirus outbreaks as soon as possible to eliminate the virus.

About 200,000 residents and visitors in Discovery Bay, an area that is home to many expatriates, were ordered to test for COVID-19 after the government said it detected coronavirus in sewage samples.

Large crowds thronged to testing centres across the city, with some residents complaining that they were more likely to get infected while queuing.

Typically, thousands of residents are mandated daily to test if they have been to an area where infections are detected.

Lam said the city was not able to try to live with the virus, as most of the rest of the world is doing, because more than 50% of the elderly have not been vaccinated.

About 80% of the city's residents have had at least one vaccine shot but many elderly people have been hesitant.

Two elderly patients in their 70s died from coronavirus, authorities said on Wednesday.