The government “will not hesitate to take further action if necessary” to stop the spread of the Indian coronavirus variant after cases more than doubled in a week, Matt Hancock has said.
The rising number of cases of the variant could put the so-called 21 June 'Freedom Day' at risk for some areas, with Boris Johnson not ruling out local lockdowns as one way of containing it.
Data from Public Health England (PHE) shows a rise in cases from 520 to 1,313 this week in the UK, with the agency saying cases were "rising in the community".
The prime minister said the government was “anxious” about the variant, saying "there is a range of things we could do, we are ruling nothing out".
But he said despite the spread of the Indian variant, there was “nothing that dissuades me” from easing England’s lockdown on Monday or the further steps towards normality on June 21.
But he added "there may be things we have to do locally and we will not hesitate to do them if that is the advice we get".
Paul Hunter, professor in medicine at the University of East Anglia, said the 21 June lockdown lifting in England could be in doubt if the variant causes increases in cases in elderly people and a rise in people needing hospital care.
He told BBC Radio 4’s Today programme: "I think the big question is how many of people who are getting the Indian variant will end up requiring hospitalisation.
"And at the moment the hospitalisation rate doesn’t seem to be increasing yet, although if this becomes much more common we’ll almost certainly see some increase, so I think it’s certainly a concern."
Watch: Boris Johnson 'anxious' about spread of Indian variant
He added: "If the Indian variant of the epidemic continues to increase at the same rate as it has over recent weeks, we’re going to have a huge number of cases by June.
"The issue though is that because it seems to be spreading in unvaccinated younger people at the moment and not yet that much more active in older people maybe we’ll be able to weather it and we’ll still be able to have the step four in June.
"But if that increases cases in elderly and starts to increase hospitalisations, and puts pressure on the NHS again then I think step four would be in doubt."
Various options are being considered to halt the spread of the variant, with one possible response to bring forward the date for a second dose of vaccine for eligible groups to increase protection.
In Bolton, which has one of the highest case rates of the variant in the country, mobile testing units have been deployed and door-to-door PCR Covid testing has been offered to 22,000 residents.
A vaccine bus has been set up to encourage uptake among those who are eligible and a rapid response team of 100 nurses, public health advisers and environmental health officers has been sent to the area.
Surge testing has been deployed in Sefton, Merseyside, after cases of the Indian variant were confirmed in the Formby area, with anyone over 16 who lives, works or studies in the area urged to take a PCR test.
Measures have also been brought in elsewhere, including in parts of London.
The health secretary said: "We are monitoring the situation very carefully and will not hesitate to take further action if necessary.
"It is imperative we all continue to be vigilant, and if you live in one of the 15 areas where we’ve introduced surge testing, make sure you get a free PCR test.
"And everyone who’s eligible needs to come forward and get a jab."
Dr Susan Hopkins, COVID-19 strategic response director at PHE, said: "We need to act collectively and responsibly to ensure that variants do not impact on the progress we have all made to drive down levels of COVID-19 and the increased freedom that brings."
Local lockdowns are only expected to be used if evidence suggests they are necessary to contain or suppress a variant which escapes the vaccine.
But any attempt to put new restrictions in place is likely to spark a backlash.
Tory Steve Baker, deputy chairman of the COVID Recovery Group of MPs, said: "Why on earth would we lock down when the vaccines continue to break the link between cases and hospitalisations and deaths?”
Greater Manchester Mayor Andy Burnham, who fought the government over local restrictions in Manchester last year, also warned against attempts to impose local measures.
He told the BBC’s Newscast: "We would be very concerned about the government putting Blackburn, Bolton, anywhere to be honest, under local restrictions when the rest of the country is unlocking."
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