Professor Chris Whitty has warned of a surge of coronavirus and more deaths if the easing of lockdown restrictions is rushed.
England’s chief medical officer, Professor Whitty was speaking at the Commons science and technology committee where he said there is going to be a ‘further surge’ and some people will ‘go on to die’.
Professor Whitty delivered a warning that despite the country’s improved virus situation, rushing the lockdown easing process could result in another wave.
Responding to questions from MPs this morning about the government’s road map for lifting coronavirus restrictions, Prof Whitty explained why, and when we could expect the next wave.
He said: "The vaccine rollout is hugely successful’ as he paid tribute to all those playing a part."
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But he said the majority of people have so far had just one dose - which does not provide the maximum level of protection.
He added: "Even when people are fully vaccinated a significant minority, it's not large but a significant minority do go on to get significant disease. It's not zero.
"There are some people who have chosen not to, or have not been able to be vaccinated who will also be at risk.
"Finally there are people who are at risk in the lower age groups. So the modelling is just reflecting the fact that because this is such a common virus against large numbers of people - even if you have a relatively small proportion of people still remaining vulnerable - that still equates to a very large number of people overall."
Last month, Prime Minister Boris Johnson unveiled his lockdown-lifting roadmap, which is being done at five-week intervals and started with the reopening of schools this week.

Mr Johnson hopes that this steady approach will mean the country can reach something close to normality by late June.
However, Prof Whitty added: "I think what we're going to see is as things are opening up, what all the modelling suggests is at some point we will get a surge in virus, and whether that happens - we hope it doesn't happen soon but, but might for example happen later in the summer if we open up gradually or if there's a seasonal effect that might happen over the next autumn and winter.
"But I think all the modelling suggests there is going to be a further surge and that will find the people who either have not been vaccinated or where the vaccine has not worked, and some of them will end up in hospital and sadly some of them will go on to die.
"That is the reality of where we are with the current vaccination. And the current modelling does make a number of assumptions ... but broadly that is the reason why we're expecting to see further deaths, although the ratio of cases to deaths will go right down as a result of vaccination - but not right down to zero."