Sage expert Sir Jeremy Farrar has said he believes “more than one” coronavirus vaccine will be available by the beginning of next year.
Farrar told Sky News' Sophy Ridge On Sunday he believed that much stricter social distancing measures would be needed until the vaccine is ready.
He said: "I do believe the vaccines will be available in the first quarter of next year, I do believe that monoclonal antibodies to treat patients and save lives will be available in the coming months.
"It's with that context that I think we need to reduce transmission now and we need to get ourselves back to the beginning of September as a country, not in piecemeal, not in fragments across the country, but as a whole country."
Farrar added: "Christmas will be tough this year. I don't think it's going to be the usual celebration it is and all families coming together, I'm afraid.
"I think we have to be honest and realistic and say that we are in for three to six months of a very difficult period.
"The temperatures drop, we are all indoors more often, we have the other infections that come this time of year. It's much better for us to be upfront and honest now."
Farrar said he believed that the government had made a mistake by not implementing a so-called “circuit breaker” short-term lockdown.
He claimed it was not too late to stem the large rise in infections and said the "second best time" for a national lockdown is now.
Farrar said the scientific advice given to the government said that the best course of action would have been to impose a circuit breaker on around 20 September, but it was not followed.
"You either have to go very early and harder than you may think, and more geographically dispersed than you may think, or you go incrementally, one week after another or one fortnight after another to try and introduce the restrictions,” he said.
"I am in favour of going earlier, I think when you go earlier the restrictions can be less draconian and you can have a bigger impact on transmission, and critically get that R value to 1 and below 1.
“That's what we’ve got to aim for – it has to be the objective."
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