The new covid variant, known as the Omicron variant, has seen another change to the rules in the UK.
From tomorrow (Tuesday), there will be an increase in restrictions, with more mask-wearing required and more rules around travel.
Although variants of a virus are common, PM Boris Johnson has implemented rules to keep people safe while experts study the new strain.
Here are three things that will be changing:
As was previously the case, face masks will be required on public transport from tomorrow (Tuesday).
This is something that’s already in place in Scotland, Northern Ireland and Wales.
The rule changes will be reviewed by the government in three weeks.
People coming back to the UK from abroad will now have to take a PCR test by the end of the second day after their arrival.
They will also have to self-isolate until they receive confirmation that their test is negative.
Rules around masks in secondary schools across the UK are being made stricter.
Secondary schools are now being “strongly advised” to reintroduce mask wearing in shared areas.
The education secretary said he wanted to make sure schools and colleges are “as safe as possible.”
The rules will also apply to staff and visitors at all schools and childcare settings.
There are still no requirement for primary school children to wear them.
Where am I not required to wear a mask?
Masks have not been a legal requirement in England since July, but this has changed for public transport, schools and shops.
However people in England will not be required to wear masks in restaurants and cafes – although it is down to preference.
Rules are unchanged for those who are exempt to wear masks for medical reasons.