People who test positive for coronavirus or show symptoms in the UK should now isolate themselves for at least 10 days, instead of seven.
The change, announced by leading UK doctors, comes as ministers try to prevent a resurgence of the virus.
So far, those showing key symptoms (a continuous new cough, a temperature or loss of taste or smell) have had to isolate themselves for at least a week.
The new advice is in line with the guidance of the World Health Organization.
The chief medical officers said the change is “particularly important to protect those who have been protecting themselves, and before fall and winter, when we can see further transmission from the community.”
It comes after the prime minister warned of signs of a “second wave” of the pandemic in parts of Europe.
Speaking at the BBC breakfast before the announcement, Health Secretary Matt Hancock said the government wanted “to take a precautionary approach” and “protect people from that wave that hits our shores.”
There have also been concerns about various local outbreaks across the UK, including Oldham, Wrexham and Staffordshire.
Meanwhile, the government is also expected on Thursday to review the restrictions in Leicester again, a month after the city was put on a prolonged blockade following a surge in cases.
The UK requirement for people who tested positive for seven days was always on the low side – many other countries require 10 days or even more.
Since the coronavirus is new, there is still a lack of certainty about how long someone remains infectious, so there are a variety of approaches.
Research suggests that the most infectious period is just before symptoms begin and for the first few days afterward, that’s what makes a virus so difficult to contain.
But UK health officials say there is now enough evidence to point to a “low, but tangible” risk of seven to 10-day transmission, even for those with mild to moderate illness.
This is a decision that could have been made weeks, even months ago, indeed.
But officials describe it as a “value judgment” based on a variety of reasons.
The availability of widespread testing means that only those with a positively confirmed infection should continue to isolate themselves: early in the pandemic, the lack of evidence meant that a general approach had to be taken, so anyone with symptoms had to isolate themselves.
It is also about sending an important signal. Infection levels are low, but the message is clear: we cannot be complacent.
Professor Peter Openshaw, part of an agency that advises the government on respiratory viruses, told the BBC Today program that most transmission occurs “at the time symptoms develop, possibly for two days. before”.
However, he said 10 days would be a “safer margin” because there have been “rare cases” in which people have been able to transmit the virus for up to nine days.
“We really don’t know that there is a lot of transmission going on in the last few days, but I think in terms of trying to pressure the virus in general now … I can absolutely understand why the government might want to introduce these changes,” he said.
Those returning to the UK from certain countries are also asked to remain in quarantine for 14 days, a move that has sparked complaints from travel companies.
Ministers are also looking for a way to reduce the current 14-day quarantine period for arrivals in the UK, meaning that quarantine and self-isolation periods could be standardized to 10 days.
Hancock told Today that the government is considering using tests to reduce the length of the quarantine period, but that there will be no imminent changes.
However, he said that new countries could be added to the quarantine list in the coming days.
On Wednesday night, the government held a meeting to discuss which other countries would join the list of those who are not exempt from the quarantine rule, after an increase in cases where Spain added over the weekend.
A high-ranking government source told the BBC that Luxembourg is likely to be added this week, but that, for now, the figures in Belgium will continue to be monitored.
On Wednesday, leading figures in the travel and airline industry called for tests for coronaviruses at UK airports, but the source said “any new system had to be viable and is not viable at the moment.”
Hancock told Breakfast that the “great scientific challenge” with evidence of border arrivals is that people “can incubate this disease for many days without showing any symptoms, and that would not appear in a test.”
Authorities said 83 other people with coronaviruses had died in the UK, bringing the total number of deaths to 45,961.
It also reported 763 other confirmed cases, bringing the total to 301,455.
What are the rules on self-isolation?
Self-isolation means staying home and not leaving.
Anyone who has tested positive for coronavirus or shown symptoms should isolate themselves for at least 10 days, and those showing symptoms should arrange to be tested.
Symptoms include:
- a loss or change in your normal sense of taste or smell
They should continue to isolate themselves if they still don’t feel well after that initial period.
Other members of your household should isolate themselves for 14 days and not leave their homes.
If your result is positive, you will be contacted by contact trackers, who will establish who else could have transmitted the infection.
Anyone who believes they are at risk will have to isolate themselves for 14 days from the point of contact.
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