Boris Johnson has set out the government’s long-awaited “roadmap” for ending lockdown in England.
If everything goes to plan, it will be 21 June at the earliest before we return to something close to pre-pandemic life.
But with so many of Britain’s most vulnerable already vaccinated, FactCheck readers are starting to ask: can’t we just go back to normal now?
Here’s what some of the UK’s top scientists say – and what we still don’t know.
Third wave worse than January?
According to papers released on Monday, the government’s SAGE committee warned ministers on 4 February that opening up over the three months beginning in April could put the NHS under even more pressure than the second wave did.
They favoured easing restrictions over a longer period – “six or nine months” starting in April – which they expected would still bring cases up, but within a more manageable level.
On 7 February, the SPI-M committee, which works closely with SAGE, updated its modelling to include more optimistic assumptions about the pace of the vaccine rollout.
But even then, the scientists warned: “Unless vaccine efficacy is significantly better than assumed here, it is highly likely that hospital occupancy would be higher than that seen in January 2021, if all restrictions are lifted by the start of May [their emphasis]”.
The government has opted for a slower timetable than this – with social distancing slated to end on 21 June – and has said it could be pushed back further if the data demands.
The latest minutes we have from SAGE – its meeting on 18 February – discuss updated models that are “consistent” with those produced earlier this month. The scientists stress the need to move slowly and say that “baseline” measures like handwashing and mask-wearing may be necessary, even once formal restrictions are lifted.
Vaccines only take us so far
But how could a third wave be worse than January when so many of the most vulnerable have since been vaccinated?
Dr Adam Kucharski, associate professor in infectious disease epidemiology at the London School of Hygiene and Tropical Medicine, explains: “this is in part because not all groups will have been fully vaccinated yet, and in part because vaccines won’t be 100 per cent protective”.
We can see this in the 7 February SPI-M paper and the government’s “Spring Plan”, published on Monday. Both assume that even if everyone who is eligible takes up the offer of a vaccine, only about two-thirds of the whole population will be protected.
That’s because about 21 per cent of people (i.e. most children) will not be eligible, and among those who are, the jab is assumed to be 84 per cent vaccine protective against infection. That leaves a third of the population without protection.
Recent data from Public Health Scotland and Public Health England suggest this efficacy figure is about right, though precise statistics continue to be revised.
In their paper on 17 February, SPI-M says that we wouldn’t achieve “herd immunity” among the unprotected group “without a further resurgence of transmission”.
And Dr Kurcharski explains that “a large epidemic could mean the remaining percentage [of people who are] unprotected translates into a large number of hospitalisations”.
Social distancing ‘doing a lot of hard work’
Dr Kurcharski also points out that “strict social distancing measures are currently doing a lot of hard work in reducing transmission in the UK”. The models used by SAGE suggest “even if a vaccine reduces transmission substantially, there could still be a resurgence if control measures are relaxed”, he says.
So the vaccine cannot automatically replace restrictions. Does that mean we’re stuck with covid rules forever? Yes and no.
The SAGE scientists say they have “high confidence” that “retaining a baseline set of policies to reduce transmission after other restrictions have been lifted would also reduce the scale of a resurgence”. These “could include hygiene and environmental measures, communications to help people reduce their own risk, and test, trace, and isolate systems” lasting into next winter.
But they say it would be possible to ease the more severe restrictions once cases have reached a very low level. From a lower starting point, the inevitable increase that relaxation brings could still be manageable. This is one of the reasons the scientists recommend moving slowly.
A 4 February SPI-M paper notes another factor in the calculation: “The longer measures are maintained that keep R below 1 [i.e. that stop the epidemic growing], the more people will be protected by vaccination and therefore the lower the risks will be over the next stage of relaxation”. So it’s partly about buying time.
SAGE also warns against moving fast because the more the virus spreads, the likelier it is to develop a mutation that might render current vaccines less effective. “Keeping prevalence low is the best way to prevent emergence and spread of such variants”, they wrote in early February.
And they also want time to measure the impact of each “step” out of lockdown. Last week, SAGE told ministers: “It will take around 4 weeks after changing a set of restrictions to see the effect in the data and be confident of the impact of changes. If a further week is required between the decision to proceed and the implementation of any changes, a gap of not less than 5 weeks between steps is advisable.”
The SAGE and SPI-M committees seem clear that we need to move slowly out of lockdown, and represent the views of a large number of experts. But the nature of science is that there are unknowns and these findings are constantly being tested and revised.
One of the main uncertainties that SAGE itself points out is what effect the vaccines have on transmission of the virus (i.e. can you be protected yourself but still pass it on?). Another is how much of the population will actually end up taking the jab and by when.
And we should bear in mind that these are models, not predictions. They look at what might happen if the government adopted certain policies, if the public responded in particular ways, if the vaccine worked to a greater or lesser extent, and so on. This can help policy makers choose between different approaches, but it’s not a crystal ball.
What about the non-health effects?
When we talk about lifting restrictions, there’s more than just the direct covid-related health effects to think about.
Huge sectors of the economy like hospitality and retail have been hit hard by the pandemic and the measures taken to control it, with businesses and employees worried about their financial futures. Meanwhile, families across the country are desperate to see loved ones and break patterns of loneliness and isolation.
These concerns are not always in direct opposition to covid restrictions – a resurgence in cases would risk returning to lockdowns, which would only compound them further. But weighing them up is not in the remit of the scientists on SAGE or SPI-M. That task falls to politicians.
The government’s SAGE and SPI-M expert committees warned the government earlier this month that if restrictions were lifted rapidly, we could see a “third wave” of hospitalisations larger than the very high levels we saw in January.
The models used by the committees suggest that even with many of the most vulnerable vaccinated, cases among young, otherwise healthy people could still put enormous pressure on the NHS if we return quickly to pre-pandemic life.
Instead, the government experts recommend a gradual easing over several months. And they cite further reasons – including buying time to vaccinate more people, reducing the chance of a variant that “escapes” existing jabs, and giving scientists a chance to assess the effect of each change before making a new one.
But this being science, that’s not the final word on the matter, and estimates and models will continue to be revised as more data emerges. There are also a number of uncertainties – particularly around how much the vaccines will prevent transmission.
Ministers across the UK face tough choices in the coming months as they weigh all this against the sometimes competing, sometimes overlapping, demands of the economy and mental health.