The UK could be at the start of a third coronavirus wave, a leading government adviser has warned.
Professor Andrew Hayward, a member of the Scientific Advisory Group for Emergencies (Sage), said the scale of spread of the Indian variant is different to previous variants, and admitted he is "very concerned" about it.
Prof Hayward's comments come as efforts continue to limit the spread of the variant, which is believed to be behind soaring COVID rates in some hotspots around the country.
According to government figures, five COVID hotspots now have rates higher than the benchmark of 100 cases per 100,000 people, despite efforts including surge testing and a push for localised mass vaccination.
Speaking on BBC Breakfast, Prof Hayward said that while "localised interventions" had helped halt the spread of other variants in the past, the Indian variant of the virus is bringing a different challenge.
Asked if the UK is at the start of a third wave of coronavirus, he said: "I think so."
He said the strain was likely to spread beyond the communities it is already in and suggested that "generalised measures" may start to be needed to control it.
Prof Hayward added that while "localised interventions" like surge testing had halted the spread of other variants, the scale of the Indian variant was different.
He said: "I’m very concerned and that largely arises from the fact it is more transmissible than the previous variant.
"While we’ve always thought we would have another wave of COVID, the size of that wave is going to very much depend on how transmissible that variant is and what proportion of the population has been vaccinated when it hits.”
Although 70% of adults in the UK have had their first dose, there are still people who aren’t vaccinated in high-risk groups.
Prof Hayward also warned that if the variant does spread widely among younger age groups, it could result in “a lot of hospitalisations” and subsequent deaths.
He said the new variant had so far proved effective at spreading within households and then the wider community, adding that he saw no reason why this spread wouldn't continue more generally around the country.
The variant, he said, would likely become the dominant strain the UK, and maybe across the world.
He added: "And that brings it back to this race between the vaccine and the virus, exceptionalities the virus just got faster."
On Wednesday, health secretary Matt Hancock announced that surge testing and additional vaccinations would be rolled out in six more areas — Bedford, Burnley, Hounslow, Kirklees, Leicester, and North Tyneside — in a bid to combat the spread.
He said there had been 2,967 confirmed B.1.617.2 infections in the UK – up 644 cases from the 2,323 he announced on Monday, which in itself was up 1,010 from 1,313 cases announced by Public Health England on Thursday.
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