As ministers proceed with lifting most of England’s restrictions next week, a third of the population is still unprotected from getting infected with Covid, scientists have estimated.
There have been about 15 million infections so far (roughly 27% of England’s population), and once partial and full vaccinations are accounted for that leaves approximately 33% of the population still susceptible to being infected with the Delta variant that is now dominant, said Matt Keeling, a professor of populations and disease at the University of Warwick and a member of a Sage subcommittee focused on infectious disease modelling and epidemiology (Spi-M).
Roughly half the UK is now fully vaccinated but Covid infections are surging again and hospitalisations are on the rise, driven by the spread of Delta and the lifting of some restrictions. On Tuesday the UK reported 50 new deaths within 28 days of a positive test, the worst daily toll since early April, and 36,660 new Covid cases.
UK: number of coronavirus deaths per day
Boris Johnson has confirmed plans to discard almost all restrictions in England next week, including mask-wearing and social distancing mandates, but has urged caution. Whether this unlocking is permanent or temporary will depend on precautions taken by the public and vaccination rates, Sage scientists have said.
Suggesting that there would be a jump in cases whenever restrictions were lifted, Johnson on Monday said it would be better to unlock now, with the “natural firebreak” of the school summer holidays, than in the autumn or winter when the NHS will be under greater pressure.
Dr Marc Baguelin, of Imperial College London and a member of Spi-M, said on Tuesday that the modelling indicated there was limited benefit to delaying the reopening. “All that’s going to do is just push things down the line – we would get slightly more vaccination, but it wouldn’t make a huge difference,” he said. But he added: “If we are opening up now, which has been the decision, then it needs to be done gradually and with care.”
Other scientists have vehemently opposed the unlocking next week, suggesting the government has decided to achieve herd immunity by in effect letting the virus run wild in young people, which they say will lead to disruptions in NHS care, education and more people getting long Covid.
The Medicines and Healthcare products Regulatory Agency (MHRA) has approved the use of the Pfizer/BioNTech vaccine for children over the age of 12, but the Joint Committee on Vaccination and Immunisation (JCVI) has not yet issued a recommendation for vaccinating under-18s.
“The difference between herd immunity by vaccination and herd immunity by infection is if you do it by infection, loads of people get ill and lots of people get really ill and stay really ill,” said Dr Helen Salisbury, a GP and medical adviser to the Health Experiences Research Group at the University of Oxford. “If you do it by vaccination, you’re in control. I cannot understand why the government would opt to do herd immunity via infection when they could do herd immunity by vaccination – I think it’s criminal.”
The latest data suggests vaccine uptake has weakened the link between infections and hospitalisations and death, but not severed it. With a high rate of infections, even a small percentage of people being hospitalised and/or dying will still be a big number, scientists have stressed. They also warn that the higher the infection rates, the bigger the opportunity the virus has to evolve vaccine-resistant variants.
“I think that the worst of the pandemic is now behind us,” said Dr Bill Hanage, an associate professor of epidemiology at Harvard University, speaking at an evidence session of the all-party parliamentary group on coronavirus. “What is being done now is actively making this part worse.”