But how quickly can the UK – and perhaps the rest of the world – hope to return to some form of normalcy? The truth is, not too soon.
Public health experts widely agree that it is not realistic to bet on the vaccine as a magic solution to end the pandemic; they say that coronavirus safeguards, such as masks and social detachment, are likely to remain in place for several months at least.
Dr. Paul Hunter, a professor of medicine at the University of East Anglia, told CNN that many factors must be considered before the UK blockade is relaxed – starting with a big drop in serious cases and deaths.
“It comes down to numbers, really,” said Hunter.
He explained that if the UK were in a position similar to that of August 2020, when the number of new cases was below 1,000 on most days – and dropped to 600 – and hospitalizations dropped below 100 and daily deaths below 10, then the country would be in a better position to ease some of the current restrictions – since the implementation of vaccination is underway.
So if a vaccine can really change things, it remains in doubt.
There are also many unknowns about the vaccines in use, such as whether or not they can interrupt transmission – and for how long they provide immunity. This means that it is possible that vaccinated people may still be able to spread the virus, or contract it later, if social distance measures are completely relaxed.
And while the UK vaccine program has been successful so far, there is another important factor to keep in mind: its coverage rates.
First, vaccines are currently available only to priority groups, which represent about 20% of the UK population: elderly, those who are clinically vulnerable and health professionals, all of whom, the research suggests, are very more likely to get the vaccine.
As the vaccine becomes available to the general population, the rate of adherence is expected to fall, as some parts of the population will be unable to take it (children and pregnant or breastfeeding women, for example) – while others may continue hesitant to accept it.
For example, several surveys have shown resistance among ethnic minority groups, including a recent study commissioned by the UK government’s Scientific Advisory Group for Emergencies (SAGE), which found that acceptance among these groups in the UK varies widely.
The study, based on surveys conducted in November, found that 72% of black or black British respondents said they were unlikely or very unlikely to get the vaccine. The Pakistan and Bangladesh groups were the second most hesitant minority ethnic group, with 42% unlikely or very unlikely to be vaccinated.
This means that certain measures may have to remain in place to protect vulnerable people in unvaccinated communities, said Hunter, noting that another increase in cases in the fall and winter is possible, depending on the percentage of the population that is immune or vaccinated until So .
But Hunter told CNN that he is hopeful that some form of normalcy may come as early as the summer, under “much more light-touch restrictions”, such as wearing a mask and social detachment.
That’s because, although vaccines may not provide herd immunity, they will help reduce transmission, as they reduce the risk of developing symptoms and serious illnesses, and symptomatic cases are about three times more likely to transmit the infection, he said. .
This in turn should push the R number to less than one – a key measure of whether the epidemic is slowing or growing.
Preliminary studies suggest that the Pfizer / BioNTech vaccine is effective against the variant seen for the first time in the UK, but on Monday, Moderna said that although his vaccine “should be protective against emerging strains detected so far”, including from the United Kingdom, early studies suggested it may be slightly less effective against the variant first reported in South Africa. Moderna said it is developing a new booster vaccine to help combat this reduction.
It is not clear whether the Oxford / AstraZeneca vaccine, which began its launch in the UK earlier this month, will be affected by the new variants. A spokesman for the University of Oxford told CNN on Tuesday that they are “carefully assessing the impact of new variants on vaccine immunity and evaluating the processes needed for the rapid development of adjusted COVID-19 vaccines, if necessary. . “
While the variants continue to present new challenges for vaccine programs, scientists are advancing models to predict what the future may bring.
Best possible scenario
A study, carried out by John Roberts, a member of the Covid-19 Actuaries Response Group, earlier this month, predicts that by the end of March, deaths in the UK could be reduced by almost 90% and that by mid-March, hospitalizations can drop by almost 60%
But the forecast model assumes a best case scenario, in which the government meets its goal of administering the first dose to all vulnerable groups by February 15 – and in which all those who receive the dose accept it.
Roberts’ model is also based on the assumption that the vaccine is 70% effective in preventing infections and 100% effective in preventing serious illnesses that would lead to hospitalizations and deaths, which the new variants now threaten.
Some experts say it is unclear whether vaccines offer complete protection against serious illness and death, arguing that clinical trials have evaluated effectiveness against the development of symptoms, but that the data was more limited in serious illnesses. Others also say that a total understanding is not realistic.
Taking these warnings into account and creating a wide range of plausible scenarios can help predict when we can expect to see an impact – which is what researchers at the University of Warwick, University of Edinburgh and Imperial College London have done.
Last week, scientists presented a wide selection of models that aim to address the various factors that put the vaccine’s launch – and its success – in question.
A model explored the options based on the implantation and adoption of the vaccine in the light of B.1.1.7. variant, first seen in the UK. The survey, conducted by Dr. Anne Cori and Dr. Marc Baguelin of Imperial College London, found that, unsurprisingly, “more restrictions would be needed to achieve the same level of control” due to the arrival of the variant, but also that 78% of the population would need to be protected – whether by vaccination or immunity, because of a previous infection – to bring the R number below one.
And with a number of uncertainties about the effectiveness of vaccines being launched, they predicted that an absorption rate of more than 80% would be necessary to achieve herd immunity – and even with a very ambitious vaccination program of 3 million doses per week, it would take four to five months to cover 80% of the UK population with the first dose.
Last week, in the UK, more than 2.5 million people received their first dose of the vaccine and 18,177 received a second dose. The researchers estimate that population immunity in the UK was 19% compared to the previous infection in mid-January.
Ultimately, imperial models found that the total lifting of restrictions before the summer “will lead to prolonged and potentially multiple periods of pressure on hospitals, and substantial additional deaths.”
Professor Mark Woolhouse and his team at the University of Edinburgh found similar results.
They mapped 44 scenarios looking at different coverage rates, variants, mixing patterns, degrees of relaxation from restrictions and how much protection the vaccine offers (versus natural protection against illness and recovery) – and saw that an extremely gradual relaxation of control measures, starting in the spring and continuing into early 2022, it would be a much less risky approach and could help get out of the pandemic without overwhelming the UK’s National Health Service (NHS).
Valuable data and surveillance
While none of the UK models can be applied to other countries, Roberts says nations that are taking approaches similar to the UK – for example, launching the vaccine to the most vulnerable groups first, along with national blockages or other restrictions severe – can see, or “hope to see” comparable results.
“This will be valuable worldwide,” he said, noting that the UK model could, in turn, help inform how other countries can plan their launches – and pave the long way back to normal life.
CNN’s Eliza Mackintosh and Krystina Shveda contributed to this report.