Could life after the vaccine mean we are back to normal? Not yet

“The problem comes down to the numbers,” Hunter said.

He explained that if the UK was in a similar position in August 2020, when the number of new cases was less than 1,000 most days – and dropped to a minimum of 600 – and hospitalizations fell from 100 and daily deaths below 10, then the country would be in a better place to ease some of the current restrictions as vaccination implementation is underway.

So if a vaccine can really change things, it remains in question.

There are also many unknowns around the vaccines in use, such as whether or not they can stop transmission and for how long they provide immunity. This means that vaccinated people may continue to spread the virus or catch it later, if social distancing measures are completely relaxed.

And while the UK vaccine program has been very successful so far, there is another key factor to consider: its coverage rates.

First, vaccines are currently only available to priority groups, which make up around 20% of the UK population: the elderly, those who are clinically vulnerable and health workers, all of whom, according to research, they are much more likely to take up the vaccine.

As the vaccine becomes available to the wider population, the adoption rate is expected to drop, as some parts of the population will not be able to take it (children and women who are pregnant or breastfeeding, for example). , while others remain hesitant to take 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 recruitment among these groups in the UK varied 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. Pakistani and Bangladeshi groups were the next most hesitant minority ethnic group, with 42% unlikely or very unlikely to be vaccinated.

This means that certain measures may need to remain to protect vulnerable people from unvaccinated communities, Hunter said, noting that another increase in cases in the fall and winter is possible, depending on the percentage. of population that is immunized or is vaccinated by then. .

But Hunter told CNN he expects some form of normalcy to arrive as early as the summer, under “many lighter restrictions on touch,” such as wearing masks and social distancing.

This is because, although vaccines may not provide immunity to the herd, they will help reduce transmission, as they reduce the risk of developing severe symptoms and disease, and symptomatic cases are about three times more likely to transmit the infection, he said.

In turn, this should increase the number R below one, a key measure of whether the epidemic is shrinking or growing.

Preliminary studies suggest that the Pfizer / BioNTech vaccine is effective against the variant first seen in the UK, but on Monday, Moderna said that while its vaccine “is expected to be protective against emerging strains detected so far, ”including that of the UK, early studies have suggested it may be slightly less effective against the variant first reported in South Africa. Modern said she was developing a new booster vaccine to help combat that reduction.

It is unclear whether the Oxford / AstraZeneca vaccine, which began its implementation in the UK earlier this month, will be affected by the new variants. An Oxford University spokesman told CNN on Tuesday that it “carefully assesses the impact of the new variants on vaccine immunity and assesses the processes needed for the rapid development of adjusted COVID-19 vaccines, should they be necessary “.

While variants continue to present new challenges for vaccine programs, scientists are moving forward with models to predict a vision of what the future may hold.

The best of cases

A study, developed by John Roberts, a member of the Covid-19 Actuaries Response Group, earlier this month predicts that deaths in the UK could be reduced by almost 90% by the end of March and that by mid-March hospitalizations could fall almost 60%

But the forecast model assumes a scenario at best when the government meets its goal of administering the first dose to all vulnerable groups by Feb. 15, and where all those who are offered a vaccine they 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 illness that would lead to hospitalizations and deaths, which is now threatened by new variants.

Some experts say it is unclear whether vaccines offer complete protection against serious illness and death, arguing that clinical trials have evaluated efficacy against symptom development, but that data were more limited on serious illness. Others also say a complete uptake is unrealistic.

Taking these warnings into account and creating a wide range of plausible scenarios could help predict when we can expect to see some impact, something researchers at the University of Warwick, the University of Edinburgh and Imperial College London have done.

Last week, the scientists presented a wide selection of models that aim to address the various factors that call into question the launch of the vaccine and its success.

One model explored options based on vaccine release and uptake in light of B.1.1.7. variant, first seen in the UK. The research, conducted by Dr Anne Cori and Dr Marc Baguelin of Imperial College London, found that, unsurprisingly, there should be “more restrictions on achieving the same level of control” due to the arrival of the variant, but also that 78% of the population should be protected, either by vaccination or immunity, due to a previous infection, to bring down the R number.

And with several uncertainties about the effectiveness of the vaccines that were deployed, they predicted that there should be a catch rate of over 80% to achieve herd immunity, and that even with a very ambitious vaccination program of 3 million doses a week, it would take four to five months to cover 80% of the UK population with their first dose.

Last week in the UK, more than 2.5 million people received the first dose of vaccine and 18,177 received a second dose. Researchers estimate that population-level immunity in the UK was 19% from the last infection in mid-January.

Ultimately, imperial models found that the total removal 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.

We plotted 44 scenarios on different coverage rates, variants, mixing patterns, degrees of relaxation of restrictions, and how much protection the vaccine offers (compared to natural protection for getting sick and then recovering) and saw that a relaxation extremely gradual control measures, from spring to early 2022, 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 monitoring

While none of the UK models can be applied to other countries, Roberts says nations that take similar approaches to the UK (e.g., first deploying the vaccine to the most vulnerable groups, along with national blockades or other severe restrictions ), could see, or “hope to see,” comparable results.

“This will have value around the world,” he said, noting that the UK model could, in turn, help report on how other countries could plan its deployment and prepare the long road to normal life. .