A government adviser on the pandemic said on Sunday that antibodies generated by Covid vaccines should last for at least a year, adding that he hoped the BioNTech vaccination programme could resume in a week.

Speaking during a television interview, David Hui said studies were still ongoing about the period of protection that coronavirus jabs offered, but some data showed the level of antibodies produced by inoculation was higher than that in recovered coronavirus patients – who had protection lasting between six to nine months.

The Chinese University professor added that generally two doses of the vaccine was sufficient.

He said he hoped the BioNTech vaccination programme could resume in a week, after the German manufacturer finished examining why some batches had faulty packaging.

“They have examined the procedures of transportation, refrigeration and dilution, and found nothing wrong. The quality [of the jabs] are fine. But perhaps changes in air pressure during the flight have affected the vial caps. The jabs with faulty caps, along with some randomly picked non-defective jabs, are being sent to Germany for some final checks. Hopefully the problem will be solved in a week.”

Professor Hui said the government may need to open more vaccination centres to catch up for lost time, after BioNTech jabs were suspended on Wednesday.

The local distributor for BioNTech, Fosun Pharma, said the German firm had submitted an interim investigation report on the issue, confirming that only the transportation of the jabs was to blame for the packaging defects.

Fosun Pharma said it was considering sending another batch of the jabs to Hong Kong and Macau, for timely resumption of the inoculation programmes.