Scotland will need to deliver nearly 80,000 jags each day due to the rapid spread of the Omicron variant, MSPs have been told.
Deputy First Minister John Swinney told a Holyrood committee on Thursday that he cannot rule out the need to introduce stricter rules over the Christmas holiday period.
The Covid-19 Recovery Committee heard from Mr Swinney, national clinical director Jason Leitch and civil servants on Thursday morning.
Derek Grieve, head of the Scottish Government’s operational vaccines division, said Hampden in Glasgow will open as a mass vaccine centre next week, while the Edinburgh venue will also become available for booster jags.
Mr Swinney urged people to reduce their social interactions before and after Christmas, as he said anecdotal evidence suggests more people are now working from home.
He said: “I have to acknowledge that given the rapid pace of increase of Omicron cases, and the data that was shared by the Prime Minister and the chief medical officer yesterday, reinforces the points the First Minister was making on Tuesday on the severity of the threat.
“I cannot rule out that we might have to apply further constraints.”
Professor Leitch also spoke about the pressure the NHS is expected to come under in coming weeks, saying the timing of the latest variant is “horrid”.
He said: “We’re at the foothill of the wave just now, which is why we’re asking people to help us control that wave as much as they can.
“That would suggest peak in January, that would suggest peak hospitalisations two weeks after that peak.”
The number of hospital cases which will lead to intensive care and death are not certain, he said, but he added that early evidence from Scandinavia is “not encouraging”.
England’s chief medical officer Professor Chris Whitty has said the Omicron wave sweeping the UK will “peak quite fast”, as he suggested there were some “really key bits of information” missing that would inform the need for a lockdown.