The 31,340,507 Britons who have received both coronavirus vaccine doses, and therefore have maximum protection against the disease, are still subject to the same rules as everyone else.
This includes the requirement to self-isolate for 10 days after coming into contact with someone who tests positive for the virus.
However, the government is now planning to scrap this rule for double-vaccinated people. Here is everything we know about the plans so far.
What will the new scheme look like?
The plans, first reported by The Times on Saturday, could see double-vaccinated people who come into contact with a COVID-19 carrier being spared the 10-day isolation requirement when contacted by the test and trace system.
Instead, the paper reported, people will be offered the chance to take a test every morning for a week.
What has the government said about it?
Health secretary Matt Hancock confirmed on Monday that the government “will” scrap the isolation period for double-jabbed people.
He told BBC Breakfast a pilot has been launched “to check that that will be effective, but it is something that we’re working on”.
He added: “We’re not ready to be able to take that step yet, but it’s something that I want to see and we will introduce, subject to clinical advice, as soon as it’s reasonable to do so.”
When will the isolation rules for double vaccinated people be scrapped?
In its report, The Times said the plan will only be approved if England’s chief medical officer Prof Chris Whitty is satisfied with the results of the pilot, which is said to involve 40,000 people.
What is the science behind dropping isolation rules for double-vaccinated people?
As the government’s chief scientific adviser Sir Patrick Vallance said last week, vaccines are “very, very effective”.
Against the Delta variant of the virus, which was first identified in India and is now dominant in the UK, two doses give an estimated 92% reduction in hospitalisations.
However, two doses are slightly less effective – an estimated 80% reduction – in preventing symptomatic COVID.
Presumably, this would be the thinking behind the requirement to take a daily test as a condition of not having to isolate.
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Prof Adam Finn, who is a member of the Joint Committee on Vaccination and Immunisation, which advises the government, told Times Radio of the idea on Saturday: “We know that the vaccine, particularly after two doses, is highly effective at stopping you from getting seriously ill, 20 times less likely to end up in hospital.
“We also know that it will reduce your chances of getting milder illness and infecting other people, but it’s probably less good at doing that than it is preventing you getting seriously ill – so it’s a kind of balance of risk thing.”
What about holidaymakers?
One of the UK’s top public health experts suggested on Sunday that vaccination status will inform the government's international travel rules in future.
Dr Susan Hopkins, strategic response director for COVID-19 at Public Health England, said there may be “alternatives to isolation” for holidaymakers who have been double vaccinated.
Asked if there is a chance those who have had two jabs could go abroad, she told the BBC’s Andrew Marr Show: “We’ll be looking at the evidence from other countries."
She said officials are looking at places like Israel, which is ahead of the UK in its vaccine rollout: "They are allowing their population to travel more."
Dr Hopkins added: "We are moving steps forward, and I think that in a time in the future, I’m not sure when, I can imagine a situation where we will have alternatives to isolation for people who have two doses of the vaccine.”
Currently, there are 11 destinations on England's "green list", which removes the need for isolation upon return to the country. However, travel to a number of these places, for example New Zealand, is unviable due to strict border measures there.
There are dozens of countries on the "amber list", from which travellers must isolate for 10 days upon return, as well as book two tests. The government advises only essential travel to amber countries.
However, Boris Johnson has played down suggestions that restrictions on foreign travel could be lifted as more people received the vaccine.
Speaking during a visit to a laboratory in Hertfordshire on Monday, the prime minister said: “I want to stress that this is going to be, whatever happens, a difficult year for travel.
“There will be hassle, there will be delays, I am afraid, because the priority has got to be to keep the country safe and stop the virus coming back in.”
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