Cornwall, which had also been in Tier 1, and Herefordshire, meanwhile, go from Tier 1 to Tier 2.
He said the number of cases was rising at the "new" mutant variant that spreads faster is a "game changer". Outdoor exercise is still permitted, however, and support bubbles remain in place under Tier 4 guidelines.
Case numbers have almost doubled in Cambridgeshire in the most recent week, with the most rapid increases seen in South Cambridgeshire, Huntingdonshire and Cambridge.
People must reduce non-essential contact with anyone outside of their household /support bubble to the absolute minimum and can meet with only one other person from another household outdoors, socially distanced at all times.
The changes means a total of 24 million people will now be in Tier 4, or 43% of the population of England.
The county council will be working with large employers to make sure they are getting all the support they need to remove barriers for testing and self-isolating, and be helping businesses who may be confused by rule changes.
Prime Minister Boris Johnson established the new Tier 4 on Saturday, now the toughest level of restrictions.
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To date, 3,644 people have been vaccinated, majority health care workers in the Vancouver Coastal and Fraser Health regions. Food and Drug Administration also authorized Moderna's coronavirus vaccine for emergency use in the United States.
Ugur Sahin, the chief executive of BioNTech, said on Dec 22 that "we don't know at the moment if our vaccine is also able to provide protection against this new variant", but because the proteins on the variant are 99 per cent the same as the prevailing strains, BioNTech has "scientific confidence" in the vaccine.
It comes as the Health Secretary announced that two new cases have been detected of yet another foreign Covid strain. That means continuing to wash your hands or using hand sanitiser often, wearing a face covering in public places such as shops and on public transport, and keeping two metres apart.
Those living in Tier 4 restrictions must not leave their homes or gardens except for work, education, and essential activities. "We've got to keep on going with this".
During a press conference from Downing Street on Dec 16, Professor Chris Whitty commented on whether social distancing would end after the vulnerable receive their jabs, or if we would reach herd immunity before the vaccination programme ends.
Dr Matt Tyrer, Cheshire East director of public health, said: "We have been seeing a worrying increase in infection rates across the borough and neighbouring areas".
"It's important that we all minimise our social contact as much as is possible this Christmas and that will help protect ourselves, our loved ones and the whole country".
"There is hope for the future as we now have a safe and effective vaccine which is being rolled out nationally. We'll be back as soon as we can!"