Hong Kong and Macau suspended the use of Pfizer-BioNTech vaccine on Wednesday after packaging defects were found on one batch of the shots.
Both cities’ governments said on Wednesday morning that they were notified by the vaccine’s Chinese distributor, Fosun Pharmaceutical Group, about packaging flaws on the bottle lids of one batch of the vaccine.
In a Wednesday statement, Fosun said it learned about “small amounts of defects related to the vial bottles” from manufacturer BioNTech on Tuesday evening.
The governments said BioNTech and Fosun had no reasons to believe the products had safety issues, but their use had been suspended as a precautionary measure as the companies investigated the defects. Hong Kong also suspended the use of another batch of the same vaccine.
The suspension dealt a blow to Hong Kong’s vaccination campaign, which has been slow due to low COVID-19 transmission numbers in the city and public distrust in the pro-Beijing government.
Hong Kong has ordered up to 7.5 million shots of the Pfizer/BioNTech mRNA vaccine, all of them to be manufactured in Europe, the government said in December. More than 1.3 million shots have been delivered.
Before the suspension, residents aged 30 or above can choose between the mRNA vaccine developed by Pfizer-BioNTech and an inactivated vaccine made by Chinese company Sinovac, which has yet to publish studies on its late-stage clinical trials. Although most of Hong Kong’s top officials have taken the Chinese vaccine, the Pfizer-BioNTech shot had been more popular with the general public.
On Wednesday, people who booked to get the shot were disappointed to find the vaccination centers were closed. Those who have received the first dose were wondering if their shots could be defective, or if they could get the second injection on time.
The recommended interval for first and second doses is 21 days for Pfizer-BioNTech vaccines, although an extension to up to 42 days is permissible, according to the U.S. Centers for Disease Control and Prevention.
Siddharth Sridhar, a virologist at the University of Hong Kong, said scientists need details about the defective package to make an assessment, but those who have got the vaccines should stay calm for now.
“We have no evidence at all that this packaging issue affects the efficacy of the vaccine,” he said. “We also haven't seen worrying safety signals over the last few weeks of the roll out.”
Fosun Pharmaceutical and BioNTech did not respond to requests for comments.
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