Covid cases have shot up by more than 50% in a week - with nearly half a million confirmed cases across the UK.
Scotland has seen a sharp rise in new cases, with parts of the country accounting for the UK's worst hotspots.
Experts now believe the BA.2 sub-variant of Omicron - which has been branded Stealth Omicron - accounts for 80% of Covid cases in Scotland.
It has a faster rate of transmission than the original version of Omicron - although it is not thought to lead to more severe illness.
The latest Department of Health data shows 492,103 people have tested positive for Covid in the past seven days across the UK, up 47,902 since yesterday.
Cases over the past seven days are 52.4% higher than the week before, with 169,186 more confirmed infections.
Each of the 10 towns and cities with the highest infection rates are in Scotland, with Na h-Eileanan Siar recording a rate of 2,252.8 cases per 100,000 people - two-and-a-half times the rate in England's worst hotspot.
Today First Minister Nicola Sturgeon told the Scottish Parliament: "The increase in cases over the past three weeks has been driven by the BA.2 sub-lineage of the Omicron variant, which is estimated to be significantly more transmissible - with a growth rate since mid-February perhaps 80% greater than original Omicron.
"BA.2 is now our dominant strain, accounting for more than 80% of all reported cases.
"BA.2 has become dominant in Scotland earlier than in England and Wales, hence the more rapid increase in cases here than south of the border in recent weeks - although cases and hospital admissions are now rising sharply again in England too."
Department of Health data shows 13,548 people were in hospital with the virus on Monday, of which 280 were in ventilation beds.
NHS chiefs in England have previously said that just under half of those admitted with the virus were primarily being treated for another condition.
The UK's 10 worst Covid hotspots are all in Scotland
- Na h-Eileanan Siar - 2,252.8 cases per 100,000 people
- East Ayrshire - 2,018.9 cases per 100,000 people
- North Ayrshire - 1,933 cases per 100,000 people
- Orkney Islands - 1,870.5 cases per 100,000 people
- Clackmannanshire - 1,858.1 cases per 100,000 people
- Falkirk - 1,814.9 cases per 100,000 people
- East Dunbartonshire - 1.,768.3 cases per 100,000 people
- West Dunbartonshire - 1,748.9 cases per 100,000 people
- South Lanarkshire - 1,720 cases per 100,000 people
10 worst Covid hotspots in England
- Somerset West and Taunton - 1,005.7
- Hastings - 981
- Worthing - 956.4
- East Cambridgeshire - 937.1
- Waverley - 927.7
- North Somerset - 923.6
- South Cambridgeshire - 907.4
- Mid Sussex - 905.7
- Cambridge - 886.8
- Horsham - 883.3
Case rates in each region
- Scotland - 1,447.6 cases per 100,000 people
- Northern Ireland - 842.7 cases per 100,000 people
- South West - 754 cases per 100,000 people
- South East - 716.5 cases per 100,000 people
- East of England - 677.7 cases per 100,000 people
- East Midlands - 505.7 cases per 100,000 people
- London - 476.6 cases per 100,000 people
- North West - 433 cases per 100,000 people
- West Midlands - 396.1 cases per 100,000 people
- Yorkshire and The Humber - 380.7 cases per 100,000 people
- North East - 349.1 cases per 100,000 people
- Wales - 268.8 cases per 100,000 people
Earlier today Nicola Sturgeon announced that the legal requirement to wear a face-covering on public transport will remain in place as cases rise.
Ms Sturgeon told the Scottish Parliament that the legal requirement for businesses to keep customers' details in case these are needed for contact tracing will end as planned on Monday, March 21.
But speaking about requirements on the wearing of face coverings, she said: "Given the current spike in case numbers, we consider it prudent to retain this requirement in regulation for a further short period."
The First Minister added: "Ensuring continued widespread use of face coverings will provide some additional protection - particularly for the most vulnerable - at a time when the risk of infection is very high, and it may help us get over this spike more quickly."
The legal requirement will be reviewed again in two weeks' time, she added, with Ms Sturgeon saying the "expectation" was that it will become guidance rather than the law in "early April".
She went on to tell MSPs that advice on testing would also change next month, saying that from April 18 "we will no longer advise people without symptoms to test twice-weekly".
