HONG KONG: Hong Kong and Macau suspended the use of Pfizer-BioNTech's COVID-19 vaccine on Wednesday (Mar 24) after being informed of a packaging problem affecting one batch of vials, while stressing they did not believe there was a safety risk.
The stoppage is the latest blow in efforts to roll out mass vaccination programmes against a deadly virus that has killed more than 2.7 million people around the world and hammered the global economy.
"For the sake of precaution, the current vaccination must be suspended during the period of investigation," Hong Kong's government said in a statement.
Both Chinese cities said their decision came after they were contacted about the issue by Fosun, the Chinese pharmaceutical company that is distributing the Pfizer-BioNTech vaccine in China.
Vials with the lot number 210102 were found to have defective packaging, authorities said.
The statements from Hong Kong and Macau did not give any details on how the packaging was defective but both said they did not believe there were any safety issues.
On Wednesday, Hong Kong authorities told several vaccination centres to stop using the Pfizer/BioNTech vaccine, according to notices seen by residents.
Some Hong Kong residents took to social media to say their appointments that day had been cancelled and that some vaccination centres were closed.
"I haven't lost confidence in the vaccine but I'm quite disappointed as I took the day off," one man, who gave his surname as Wong, told AFP as he arrived at a taped-off centre.
Vaccines with the lot number 210102 have already been given to members of the public in Hong Kong.
The city began vaccinating residents with doses from Sinovac in February and began offering the one developed by Pfizer and its partner, BioNTech, in March.
Authorities in Hong Kong said another batch of vaccines with lot number 210104 would also be suspended until further notice.
Despite being a notoriously packed city, Hong Kong has kept infections low thanks to some of the most stringent quarantine measures in the world, recording 11,000 infections and 200 deaths since the pandemic began.
Hong Kong began its vaccination drive last month but the public take-up has been slow and ensnared by roiling political unrest.
The city was upended by huge and often violent protests in 2019 that Beijing has responded to with a sweeping crackdown on dissent.
As a result, public trust in Hong Kong's government is low. A recent poll said only 37 per cent of Hong Kong adults planned to get vaccinated.
As of Tuesday, 403,000 people - about 5 per cent of the city's population - have had their first shot.
The Pfizer-BioNTech vaccine has shown greater take-up since its launch with the number of residents booking that shot more than double those booking Sinovac over the past week, according to government figures.
Sinovac received fast-track approval despite not publishing peer-reviewed clinical data.
The data available points to an efficacy rate of between 50 per cent and 80 per cent, depending on the studies.
Pfizer says its efficacy rate is 94 per cent to 95 per cent.
The vaccination scheme was opened to anyone above the age of 30 last week after officials struggled to attract enough elderly people and those in priority groups.
Hong Kong leader Carrie Lam has previously lamented the tepid enthusiasm for vaccination and accused critics of "smearing" the Chinese vaccine.
On Tuesday, health authorities banned a local clinic from supplying vaccines after one of its doctors publicly said he would choose Pfizer's vaccine over Sinovac.