Coronavirus cases involving the Indian variant have nearly doubled in the space of four days, health secretary Matt Hancock has said.
Hancock told MPs on Monday there are now 2,323 confirmed cases involving the B.1.617.2 variant.
This is up 1,010 from the 1,313 infections announced by Public Health England on Thursday.
Hancock said that of the 2,323 cases, 483 have been seen in Bolton and Blackburn with Darwen – where it’s now the dominant strain of the virus.
Speaking in the House of Commons, he said COVID-19 hospitalisations in Blackburn are "stable" with eight people being treated, while there are 19 in hospital in Bolton.
He said the majority of these people are eligible for a vaccine but haven’t yet had one.
"This shows the new variant is not tending to penetrate into older, vaccinated groups and it underlines again the importance of getting the jab especially – but not only – amongst the vulnerable age groups.”
Urging people to get a jab, he said: "To anyone who feels hesitant... just look at what is happening in Bolton Hospital where the majority of people in hospital with coronavirus were eligible for the jab but have chosen not yet to have the jab and have ended up in hospital – some of them in intensive care.
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“Vaccines save lives, they protect you, they protect your loved ones and they will help us all get out of this pandemic.”
Hancock added there are now 86 local authority areas where there are five or more confirmed cases of the variant.
Meanwhile, informing MPs of the latest scientific assessment on the variant, he said: “The early evidence suggests that B.1.617.2 is more transmissible than the previously dominant [Kent] variant. We do not yet know to what extent it is more transmissible.
“While we also don’t have the complete picture on the impact of the vaccine, the early laboratory data from Oxford University corroborates the evidence from Bolton Hospital and the initial observational data from India that vaccines are effective against this variant.”
He added that while this is “reassuring”, the higher transmission rate “poses a real risk”.
Earlier on Monday, Boris Johnson's spokesman admitted changes to rules on social distancing could be delayed due to the Indian variant.
A review of the current "one-metre plus" social distancing advice, along with consideration of the possible introduction of coronavirus status certification, had been expected by the end of May.
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