Three shots of the Pfizer/BioNTech Covid vaccine neutralises the new Omicron variant, laboratory tests have shown.
The vaccine manufacturers released their first joint statement on the likely efficacy of their shot against Omicron on Wednesday.
They claimed that two vaccine doses resulted in significantly lower neutralising antibodies – but that a third increased the neutralising antibodies by a factor of 25.
A new vaccine designed specifically for Omicron could be delivered by March 2022, they added.
The research found that blood obtained from people who had received their third booster shot a month ago neutralised the Omicron variant about as effectively as blood after two doses tackled the original strain of the virus.
“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine,” Pfizer chief executive Albert Bourla said.
“Ensuring as many people as possible are fully vaccinated with the first two dose series and a booster remains the best course of action to prevent the spread of COVID-19.”
BioNTech boss Ugur Sahin added that the latest data suggests a third dose “could still offer a sufficient level of protection from disease of any severity caused by the Omicron variant”.
He continued: “Broad vaccination and booster campaigns around the world could help us to better protect people everywhere and to get through the winter season.”
The news comes as the UK considers new set of coronavirus restrictions including orders to work from home and the introduction of vaccine passports to deal with rising cases and the spread of Omicron.
Downing Street sources insisted “no decisions have been made” but there is widespread speculation that further measures could be imminent.
And the Covid-O subcommittee of experts is understood to be holding a meeting later on Wednesday.
A prominent member of the Scientific Advisory Group for Emergencies (Sage) warned that a full UK-wide lockdown to deal with the threat of the Omicron variant cannot be ruled out, although the current threat posed by the strain remains unclear.
Any move to impose fresh restrictions would be viewed with suspicion in Westminster at a time when Boris Johnson is under pressure over allegations No 10 staff breached lockdown rules by holding a Christmas party last December.
The government has so far insisted it is not time to activate its Plan B – the restrictions that would be brought in to prevent the NHS being overwhelmed this winter.
But Omicron may have changed those calculations in Downing Street, with Johnson telling the Cabinet on Tuesday that “early indications were that it was more transmissible” than the Delta strain.
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