HONG KONG: Hong Kong authorities on Wednesday halted the use of a COVID-19 vaccine developed by Pfizer and BioNTech citing defective packaging, triggering scenes of confusion in inoculation centres across the city.

The suspension comes as the Asian financial hub has faced a sluggish take-up of vaccines due to dwindling confidence in China's Sinovac Biotech Ltd treatment and fears of adverse reactions.

Inoculation centre staff turned away residents booked to take the Pfizer/BioNTech vaccine, with many Hong Kong-ers unsure as to the reason and asking for explanations. Adding to the confusion, local media reports said one doctor was reprimanded for promoting the Pfizer/BioNTech vaccine over Sinovac's.

"As a precautionary measure BioNTech requested the suspension" for its vaccines in Hong Kong until an investigation is complete, the city's Director of Health, Dr Constance Chan, told a news conference on Wednesday afternoon.

The city started vaccinating residents with doses from Sinovac in February and began offering the one developed by Pfizer and its partner, BioNTech, in March.

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. Chan said the government had initially contacted Fosun Industrial (Hong Kong), the distributor of the Pfizer/BioNTech vaccine in Hong Kong and Macau, after it found some cases of cracks in vaccine containers and stains on some bottles.

She said Fosun replied on Wednesday morning stating that it needed to further investigate and would suspend vaccination until further notice.

"BioNTech and Fosun have not found any reason to believe that product safety is at risk," she said.

Fosun's parent company, Shanghai Fosun Pharmaceutical, said in a filing on Wednesday it was investigating with BioNTech.

Macau said on Wednesday it was also suspending the Pfizer/BioNTech vaccine due to the packaging flaw.

Officials said Sinovac vaccinations would continue to take place as scheduled.

WAIT AND SEE

In a separate incident, Hong Kong's government said it shut a private clinic that administered COVID-19 vaccines after a doctor surnamed Lau "violated an agreement" under the city's inoculation programme.

Broadcaster RTHK reported that Lau recommended people take the Pfizer/BioNTech shot rather than the Sinovac one due to a better international reputation for the former.

Lau did not immediately respond to requests for comment. His clinic had been providing Sinovac vaccines and not the Pfizer/BioNTech ones, which are only available at larger public sector facilities. Distrust of the mainland has intensified among residents in recent years with months of anti-government and anti-China protests driven by a perception that Beijing is pushing the semi-autonomous city onto a more authoritarian path.

Media reports of several deaths after vaccinations have also kept some people jittery even though the government has said there was no direct link between the shots and the deaths.

With low levels of infection in the city, many people are opting to wait and see before getting a shot.

"I won't get vaccinated yet, I'm going to wait until more people get it," said one 40-year-old man who gave his name as Leung.

"I have more confidence in BioNTech. It's a foreign one after all ... the quality is guaranteed." Only about 5% of Hong Kong's 7.5 million residents have been vaccinated, and more than one third of them received the Pfizer/BioNTech shot.

For one 67-year-old resident, who gave his surname as Lau, there was no question as to which vaccine he was going for on Tuesday - the Pfizer/BioNTech one.

"It has better data, there are more people getting it internationally," he said. "The other one, the data is not clear."

City leader Carrie Lam has repeated called for people to get vaccinated.

"When many places all over the world are scrambling for vaccines, we have a pretty assured supply," she said on Tuesday.