Prime Minister Boris Johnson faces a “very difficult” call on whether to drop restrictions on June 21 given the “more negative direction” of the data, according to a leading expert.
Professor Neil Ferguson, whose modelling was instrumental to the UK locking down in March 2020, said a “cautious” approach is needed as the Government balances the potential risks against a desire for normality.
The full effect of easing some restrictions on May 17, such as indoor mixing in pubs, is yet to be understood and further data is required, Prof Ferguson added.
For the Government, Communities Secretary Robert Jenrick said there is “nothing at the moment that suggests that we won’t be able to move forward” with the next stage of lifting restrictions on June 21.
Mr Johnson has come under pressure to move ahead with the June 21 unlocking – dubbed “freedom day” by some – given the huge uptake of Covid-19 vaccines in recent months.
But questions remain over the impact of the so-called Indian variant of Covid, also known as the Delta variant, on hospital admissions and deaths.
Prof Ferguson, from Imperial College London, said the variant is anywhere between 30% and 100% more transmissible than the previously dominant Kent variant, also known as Alpha.
He told BBC Radio 4’s Today programme: “We’re certainly getting more data. Unfortunately, I mean, the news is not as positive as I would like on any respect about the Delta variant.
“The best estimate at the moment is this variant may be 60% more transmissible than the Alpha variant.
“There’s some uncertainty around that depending on assumption and how you analyse the data – between about 30% and maybe even up to 100% more transmissible.”
Prof Ferguson said 60% is “a good central estimate” at the moment and noted that most people in hospital with the virus have not had a vaccination.
He added that data is still awaited on how much the Delta variant can evade the immunity which protects people against being admitted to hospital.
Asked about lifting restrictions on June 21, Prof Ferguson said: “I think the data is pointing this week in a more negative direction than it was last week, so it points towards the direction of being cautious.
“I think balancing, clearly, people’s desire – and there clearly is a built-up desire to get back to normal – against the potential risk is a very difficult judgment call.”
Asked what difference delaying the June 21 lifting of restrictions would make in terms of the scientific evidence, Prof Ferguson said: “We know at the moment that the Delta variant, the Indian variant, is doubling across the country about every nine days, with some variability place to place.
“But we haven’t fully seen the effect of what happened from May 17, step three, the relaxation of restrictions, come through into that data, so we expect that to accelerate even more.”
He said it is still unclear how increased numbers of cases will translate into hospital admissions.
“We’re seeing an uptick in hospitalisations in the North West, in a couple of other areas, but it’s just too early to say, and that’s critical because we do expect vaccines to give a high level of protection still, but exactly how high is critical to what size third wave we might see,” he said.
Mr Jenrick, appearing on the same programme, said: “We’ve got a further 10 days until we are going to make that decision on or around June 14, so during that period we’ll see where are we with hospitalisations, with deaths, where are we with the vaccine rollout – we’re doing everything we possibly can to expedite that – and then at that point, we’ll make our final decision.”
Asked whether measures such as wearing masks and working from home could continue after June 21, Mr Jenrick replied: “Well, there are options that are clearly available to the Government.”
He added: “We set out within the road map what would be expected to happen at the next stage and we want to try to stick to that if we possibly can.
“All of us are moving everything we can to achieve that. But, of course, we keep these things under review and we’re also asking people to continue to exercise caution in their daily lives.”