Professor Chris Whitty has said he fears Britons will not accept lockdown rules to fight off the Omicron super-variant over the winter because of 'behavioural fatigue' caused by two years of restrictions.
England's chief medical officer told a panel discussion hosted by the Local Government Association that he worried whether the Government could still 'take people with us'.
It comes as Belgium became the first European Union country to announce a case of the variant Omicron, which has been identified in other places including South Africa, Botswana, Hong Kong and Israel.
It is though the strain, which has more than 50 mutations - the most ever recorded in a variant and twice as many as Delta -, could be more jab-resistant and transmissible that any version before it.
'My greatest worry at the moment is that people... if we need to do something more muscular at some point, whether it's for the current new variant or at some later stage, can we still take people with us?', Professor Whitty said.
Professor Chris Whitty has said he fears Britons will not accept lockdown rules to fight off the Omicron super-variant over the winter because of 'behavioural fatigue' caused by two years of restrictions
He admitted that some of the changes the public has had to make have been 'very destructive' to society and the economy.
However, despite his worries, the chief medical officer struck a positive note, saying he believed the Government will be able to maintain public support for coronavirus measures.
'I think the extraordinary thing has been the ability of the UK population, with very, very small exceptions, to just accept that there are things we collectively have to do to protect one another and do collectively, including things that have been very destructive to social and economic situations for individuals and families,' he said.
'Obviously, we want to avoid having to do those at all if we can, and to do the minimum ones necessary, but will we be able to maintain public support?
'And I think my overall view is, I think we will.
'Provided you are clear with people what the logic is, provided they feel that we're being entirely straight with them as to all the data... but I think that's always a worry.'
Professor Whitty added that the longer the pandemic goes on, the harder it is to know what the public's response will be.
'It's easier to be confident of people's response right at the beginning than it is after people put up with two years of their lives being interfered with...
'You can only do a public health intervention on the scale we've had to do if the majority of the population — and as it turned out, the great majority of the population — support it,' Whitty said.
'What has been really clear is the great majority of people really take this very seriously and do want to have protections put in place.'
The latest YouGov polling shows public support for Christmas restrictions, such as compulsory face masks and working from home, to kerb the spread of Covid-19
He admitted the latest YouGov polling showed public support for Christmas restrictions, such as compulsory face masks and working from home, to kerb the spread of Covid-19.
But the polls revealed there was little support for a ban on indoor socialising and closing pubs and restaurants.
Professor Whitty said it was clear the UK was not 'out of the woods' but said 'the things that are probably the most important... that is heading the right way.'
He said there were three reasons for optimism - that vaccination was 'taking the edge off' school outbreaks, boosters were having a 'material impact' in reducing hospitalisations, and that the European Delta surge had not yet reached the UK.
It comes as Britain's daily Covid cases breached 50,000 today for the first time in a month and deaths crept up by 2 per cent in a week - but hospital admissions were down 12 per cent.