Amid concerns over the Indian coronavirus variant, latest government figures have revealed the five COVID hotspots where cases have risen to higher than 100 cases per 100,000 people.
Britons have been told the country is in a “straight race” to vaccinate its population in order to outrun the threat of the mutation.
England’s deputy chief medical officer Professor Jonathan Van-Tam said the jab-rate over the next few weeks would be crucial for ensuring the prime minister could lift all COVID restrictions on June 21.
More than one million people aged 34 and 35 will receive a text message on Thursday or Friday asking them to come forward for their vaccine.
The vaccine boost comes amid concerns that the Indian variant has taken hold in some parts of the country, with the clusters seemingly responsible for a sharp increase in cases.
Rates are currently highest in Bolton in Lancashire, where government figures put it at 301.5 per 100,000.
Other hotspots include Blackburn with Darwen, also in Lancashire, where the rate is currently 131.6, as well as Bedford (128.1), Derry City and Strabane in Northern Ireland (103.8) and Glasgow City (100.6).
Watch: People in virus hotspots urged to 'think carefully'
The rate of 100 cases per 100,000 people has been used by the government throughout the crisis as a benchmark for the spread of the pandemic, with concerns that health services could be overwhelmed if rates rise above that level.
Speaking at a Downing Street press conference on Wednesday, Prof Van-Tam urged people in COVID hotspots not to “tear the pants out of it” when using the new freedoms they have this week.
He advised a “cautious” approach to socialising in the coming weeks, saying that the government faces a "straight race" between the transmissibility of the virus and the vaccine rollout.
Despite having the highest rates of the virus, people in COVID hotspots have the same freedoms as other areas of the country in line with step three of four on the government's road map out of lockdown.
Asked if he would advise people in those areas against taking advantage of new freedoms, Prof Van-Tam said: "I would advise the residents in those areas to think very carefully about the freedoms they have, weigh up the risks and be very cautious.
"It is possible to do something outside, better to do it outside. If it is possible to do something with smaller numbers, with people you know rather than multiple new contacts, it’s better to do that. Take it steady.
"I think I’ve said ‘don’t tear the pants out of it’ once before from this or a similar podium, but frankly we’re back to that again now.
"The government has given people freedoms to start to make these judgments for themselves and I understand that we can’t live for years and years on end with rules, people will have to learn to manage these risks from COVID for themselves because this is not going to go away in the short term, medium term and probably the long term."
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