A billboard in Causeway Bay appeals to the public to get a COVID-19 vaccination. (@DORISCLIFE / INSTAGRAM)

HONG KONG – The Germany-produced BioNTech vaccine has been found effective against coronavirus variants prevailing in the United Kingdom and Brazil, though less effective against the one in South Africa, Hong Kong’s health experts said on Thursday.

The mRNA-based BioNtech product is one of the three types of vaccine that the Hong Kong government has procured for the city’s mass vaccination program. The government has purchased a total of 22.5 million doses, 7.5 million doses each from Sinovac, Fosun-BioNTech and AstraZeneca.

READ MORE: HK allows residents aged 30 and above to get vaccinated

The AstraZeneca jab, which is expected to arrive in the city no sooner than the second half of this year, was also found effective in fending off the UK and Brazil variants, but “basically ineffective” against the South African one, two expert committees under Hong Kong’s Centre for Health Protection (CHP) concluded after reviewing clinical data.

As for the mainland-made Sinovac vaccine, “there has not been any data available to conclude its efficacy in protecting people from being infected by any of the mutated strains,” Lau Yu-lung, chairman of the scientific committee on vaccine preventable diseases, said at a briefing.

He noted that the company is implementing a large-scale study in Brazil and more efficacy data against variants will be available.

 David Hui Shu-cheong, chairman of the scientific committee on emerging and zoonotic diseases, said people who had previously come down with COVID-19 need to wait 90 days after their recovery before getting vaccinated

Hong Kong has recorded 93 infections involving new variants since December last year, including 448 imported cases. Fifty of the infections have been categorized after genetic analysis – 37 resembling the UK variant, eight the South African one and five the Brazilian one.

On Thursday, 22,600 Hong Kong residents received their first dose of the Sinovac vaccine. From Feb 26 to Thursday, around 201,500 people received the first shot of the Sinovac vaccine and 75,100 were injected with the BioNTech vaccine.

Speaking at the same briefing, the CHP’s controller Ronald Lam Man-kin said some of the social distancing rules are likely to be relaxed when at least half of the city’s population have received the vaccines.

“In the second phrase, if we have zero locally cases … and other countries and regions also see high vaccination rates and dwindling new infections, we can further ease the curbs,” Lam said.

Lau agreed that the 50 percent vaccination rate is a threshold for lifting restrictions on visiting leisure venues, hospitals and care homes.

Lau added that if 75 percent of the local population receive the jabs, the government may start to consider the resumption of international travel. “The 75-percent vaccination rate is very challenging to Hong Kong and other places as well.”

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Also at the same briefing, David Hui Shu-cheong, chairman of the scientific committee on emerging and zoonotic diseases, said people who had previously come down with COVID-19 need to wait 90 days after their recovery before getting vaccinated.

People who have recovered from the novel coronavirus infection need only one shot as opposed to the recommended two jabs if they taking a BioNTech vaccine, said the prominent infectious disease expert from the Chinese University of Hong Kong.