HONG KONG - Officials on Wednesday (March 24) scrambled to reassure residents that the Pfizer-BioNTech Covid-19 vaccine was safe after "observed deviations" in the vial seal of one batch.

Hong Kong and Macau have announced the suspension of all Pfizer-BioNTech jabs until further notice.

The suspension in Hong Kong was announced at 10am after the authorities received written notification earlier in the day from Fosun Pharma, the distributor of the Pfizer-BioNTech vaccines in China, that there were "observed deviations" in the vial seal of one batch of the vaccine.

The government statement said BioNTech and Fosun Pharma had initiated an investigation to identify the root cause of these packaging issues but added that the two companies "have no reason to believe that there is a risk to product safety".

Hours later at a news briefing, Secretary for Civil Service Patrick Nip, who is heading the city's free and voluntary vaccination programme, apologised for the inconvenience caused.

Also at the briefing was Director of Health Constance Chan who said Fosun was going to approach the manufacturer in Germany to look into their plant there and review the entire logistics chain until the vaccines arrived in Hong Kong.

She said the group immediately affected by the suspension would be those due for their second doses this Saturday.

Dr Chan said the government would urge the manufacturer to give a report as soon as possible to see if the existing doses in Hong Kong were safe.

"If not, then they have to deliver another batch to us as soon as possible," she said. "If we cannot resume the vaccination before that, then we will refer to the advice given by the Joint Scientific Committee set up by the Department of Health for the vaccination."

Dr Chan said there were reports of problems in 57 instances. They included cracks in containers, leakage due to overpressure from vials, loose caps, as well as stains or marks on the outside of bottles.

She told the media that some 150,000 of 585,000 doses in the batch with the problem had been administered.

The latest development is a blow to the month-long vaccination programme in Hong Kong as a number of opinion polls conducted or released in January had shown that most residents were hesitant about getting inoculated.

Confidence in the procedure slid particularly after reports of deaths and adverse reactions such as facial paralysis and heart palpitations.

Ten people who have been given either the Sinovac or Pfizer-BioNTech vaccines - both of which are the only ones approved currently in the city - have died but an expert panel has already ruled out a direct link to the vaccination in all of the cases.

When asked if the suspension would further dent public confidence in vaccination, Secretary for Food and Health Sophia Chan said the government had been open and transparent with information sharing.

She said the government also had a "robust mechanism" in monitoring the shots and adverse events from them.

Prof Sophia Chan stressed that existing mechanisms ensured that the vaccines authorised for emergency use are "safe, efficacious and also of required quality".

She added that the Sinovac jabs are not affected and will continue to be administered.

More than 400,000 Hong Kong residents have received their first dose of a vaccine, with 62 per cent getting the Sinovac one.

In a separate development, the health authorities dropped a private clinic in To Kwa Wan from administering vaccines after it put up a notice that said Sinovac's "reputation is not good", while promoting the use of Pfizer-BioNTech. A photo of the notice went viral.

The clinic provided only Sinovac jabs as Pfizer-BioNTech was made available only at larger, public-sector facilities.

The Department of Health said on Tuesday that this was the first clinic to be dropped since private doctors began offering Sinovac jabs on March 2.

On Wednesday, the territory recorded 10 new infections, of which four were local.

So far, Hong Kong has recorded more than 11,400 Covid-19 cases, including more than 200 deaths.