Covid could ruin the next five Christmases as current measures to control the virus are "insufficient", an expert has warned.
King's College genetic epidemiology Professor Tim Spector warned Brits to be prepared for Covid to cause major problems for the next five years.
The lead scientist on the Zoe Covid Study app says experts now have a better understanding of the virus than last year.
Scientists in 2020 were mainly concerned about getting to the end of the year, but can now take a view into the future.
Prof Spector said: "And that's clearly turning out not to be the case, as we realise that just vaccines alone, even in countries that have got higher vaccination rates than ours, are not the final solution to this.
"But we need a combination of measures.
"We need to extend the vaccination programme to include three shots.
"We also need to realise there will be breakthrough infections that are real, we now know that vaccinated people can still transmit the virus, and that is going to be running through our populations to some degree.
"How high we want those rates to be is highly determined by our complacency and our relaxation of some of the rules that we had in place, that last year I thought we're actually over the top, and now this year, I think insufficient."
Speaking at an online conference for the Royal Society of Medicine's Covid-19 series, .Prof Spector says the ending of restrictions in July gave Brits the impression the pandemic had a "black and white" answer.
Prof Spector said: "We have to realise we just have to in some way control (it) into something that doesn't cause as much loss of life, doesn't cause morbidities, and reduce that.
"And to do that is a combination of the vaccines, the medicines, etc. But also we have to keep some public health measures in place to keep those numbers down - we're not doing that."
"And that's why for the last three months, we've had the highest rates not only of cases but also hospitalisations in western Europe.
"And I think it's pretty unwise for a country that has such a perilous health system - even at this stage about 7% of hospital beds full of Covid - at a time when we've got massive other health needs.
"So we're not doing enough, we are too complacent. The Government has a sort of a black and white approach and I think the public health messaging from the Government has been appalling."
He said the British approach to testing needs to move towards using a combination of lateral flow and antibody tests to pinpoint members of the public at risk of breakthrough infections.
His comments came as a new study revealed the amount of under 18s in England who died from Covid between March 2020 and February 2021.
The research, published in Nature Medicine, found 3,105 young people died in that time period out of England's 12,023,568 people under the age of 18.
Sixty-one of those tested positive for Covid-19 before their death.
Of the 61, 25 were due to coronavirus -1>coronavirus - with cause of death for 22 being Covid, and three due to paediatric inflammatory multisystem syndrome temporally associated with the virus.
Almost all (99.9%) of those under 18 who tested positive for Covid survived.
Those older than 10, those of BAME background and co-morbidities were over-represented in the virus-related deaths compared with other deaths in children and young people.
Researchers say the results will be key to guiding decisions on shielding and child vaccinations.
The main variant studied was Alpha, but newer variants should be evaluated in a similar way.
Russell Viner, professor of adolescent health at UCL, an author of the paper, said: "In terms of what this means for us now, we don't have updated data in this form for the last six months, although we will in the future.
"Paediatricians across the country believe that these findings still broadly hold - that children are at extremely low risk of death from this virus, most deaths of children with a positive test are not related to Covid but reflect the commonality of infection in the population, and that the children at most risk are those who have always been at higher risk - those with serious other medical conditions."
