One of the UK’s leading coronavirus experts has said the nation could be on the verge of a “substantial third wave” of infections.
Professor Neil Ferguson, the Imperial College London scientist whose modelling convinced Boris Johnson to impose the first national lockdown in March last year, said the “critical” element will be how effective vaccines are against the “Delta” variant first identified in India.
He added that delaying the end of England’s lockdown, currently planned for 21 June, would make a difference in efforts to deal with the Delta variant.
Driven by this more transmissible variant, infections have once again started to increase: 7,540 were recorded on Wednesday, the highest number since 26 February.
Speaking at a media briefing on Wednesday, Prof Ferguson said new data compiled by the Scientific Pandemic Influenza Group on Modelling (SPI-M), which advises the government, suggests: “Basically... there is a risk of a substantial third wave, [but] we cannot be definitive about the scale of that.
"It could be substantially lower than the second wave or it could be of the same order of magnitude.
“That, critically, depends on how effective the vaccines still are protecting people against hospitalisation and death against the Delta variant, as well as a few other unknowns.”
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Prof Ferguson said the doubling time of the Delta variant in the UK is just under seven days – which is “comparable with what we saw before Christmas”.
Meanwhile, one in 10 UK local council areas – 38 out of 380 – are currently recording COVID rates above 100 cases per 100,000 people. This is the highest number of areas above this threshold since 23 March.
Asked if delaying the end of lockdown from 21 June would make a difference, Prof Ferguson said: “Yes, because it allows more people to get second doses.”
Early data suggest vaccines are effective against the Delta variant. Of the 12,383 people infected with it as of 3 June, only three fully vaccinated people had been hospitalised.
As of Tuesday, the latest date for which figures are available, 54.2% of UK adults – 28,540,844 people – had received both doses of the jab.
However, Prof Ferguson said it is currently too early to predict how the rising case numbers “will translate into hospitalisations – but it is well within the possibility that we could see a third wave at least comparable in terms of hospitalisations, maybe not as severe, as the second wave.
“Almost certainly I think deaths probably will be lower. The vaccines are having a highly protective effect, cases in hospital now are milder, but it still could be quite worrying.”
He added the country has not yet seen a “huge surge in transmission” from step three of the lockdown road map on 17 May, “but that may still be coming”.
Boris Johnson is set to make an announcement on Monday confirming whether or not the 21 June unlocking will go ahead.
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