These are the latest UK coronavirus stories you need to know.
January Lockdown for Scotland
Scotland has introduced a full 'lockdown' to try to curb a surge in cases of COVID-19.
Nicola Sturgeon, Scotland's First Minister, said new restrictions lasting throughout January would be introduced at midnight in a bid to contain the new, faster-spreading strain of the SARS-CoV-2 virus.
She said the infection rate was putting "significant pressure" on NHS services.
The move has increased pressure on Boris Johnson to introduce tighter restrictions in England.
The Prime Minister is preparing to make a TV address tonight in which he will outline further measures to contain the virus.
Speaking to Sky News earlier, he warned of "tough, tough" weeks ahead.
Matt Hancock, Secretary of State for Health and Social Care for England, said when it came to a tightening of restrictions, "We don't rule anything out".
The new variant of SARS-CoV-2, lineage B.1.1.7, or VOC-202012/01, is known to be more transmissible, affecting a larger share of people under the age of 20.
A preprint study by Imperial College London (ICL) suggested it could increase the R number by between 0.4 and 0.7.
An analysis by the Scottish Government predicted that it was "very likely that this strain will further increase in dominance in Scotland in a similar way to that already seen in London and SE England".
Ms Sturgeon told the Scottish Parliament that there would be a legal requirement for people to stay at home for the rest of this month, with schools remaining closed to most pupils until the start of February, at the earliest.
"It is no exaggeration to say that I am more concerned about the situation we face now than I have been at any time since March last year," the First Minister said.
She warned that the situation facing the NHS in some areas of Scotland was now challenging, and that "if the rate of increase in case numbers that we have seen in the past two weeks was to continue unchecked, there would be a real risk of our NHS being overwhelmed, even with contingency plans in place".
Commenting on the ICL study to the Science Media Centre, Prof Jim Naismith, director of the Rosalind Franklin Institute at the University of Oxford, said: "It is not really possible to overstate how serious this new strain is."
He warned that "unless we do something different the new virus strain is going to continue to spread, more infections, more hospitalisations, and more deaths".
Mr Hancock said that areas of England currently in tier 3 were seeing increasing rates of COVID-19. "This new variant is much easier to catch, it is much more transmissible, and we're now seeing the effect of that in lots of different parts of the country, unfortunately,"" he said.
On Sunday, Sir Keir Starmer, the Labour leader, urged the Government to impose a national lockdown within 24 hours because the SARS-CoV-2 virus was "clearly out of control".
Dr Duranka Perera, treasurer of the Doctors' Association UK, warned: "If this trend continues, the unbearable conditions described in some hospitals by staff are very likely to spread nationally and could then lead the NHS to – or over – the brink."
Rollout Begins of Oxford/AstraZeneca Vaccine
An 82-year-old dialysis patient from Oxford became the first person in the world to receive the AstraZeneca/Oxford COVID-19 vaccine outside clinical trials.
Sam Foster, chief nursing officer at Oxford University Hospitals NHS Foundation Trust, who administered the vaccine at 7.30 am, said: "It was a real privilege to be able to deliver the first Oxford vaccine at the Churchill Hospital here in Oxford, just a few hundred metres from where it was developed."
Recipient Brian Pinker said he could now look forward to celebrating his 48 th wedding anniversary next month with his wife, Shirley.
Matt Hancock described Monday's deployment of the AstraZeneca/Oxford vaccine, following regulatory approval last week, as "another significant milestone in the expansion of the vaccination programme".
The Government pre-ordered 100 million doses of the vaccine.
The Department of Health and Social Care said more than half a million doses were currently available. It said tens of millions would be delivered in the coming months.
More than 730 vaccination sites have been established across the UK, with more expected to open this week, ministers said.
Initially, doses of the AstraZeneca/Oxford vaccine were sent to hospitals. Later this week, distribution is scheduled for primary care services and care homes.
More than a million people in the UK have been vaccinated with the Pfizer/BioNTech vaccine since it received regulatory approval last month.
The NHS made history when Maggie Keenan became the first person in the world to be vaccinated against COVID-19 outside of a clinical trial at Coventry Hospital on December 8.
Unlike the Pfizer/BioNTech vaccine, which requires storage at -70C, the vaccine developed by scientists at the University of Oxford can be kept at normal fridge temperature.
Concerns Raised Over Dosing Regimen
All four UK chief medical officers have endorsed a longer gap between the first and second doses of the two available COVID-19 vaccines being administered in the UK to enable more people to receive a first dose earlier.
Health chiefs say they favour giving a level of protection for the greatest number of people in the shortest time.
The move, backed by the Joint Committee on Vaccination and Immunisation, has proved controversial, with some scientists pointing out that the vaccine trials were based on two doses delivered within a month.
At the weekend, Dr Vinesh Patel of the Doctors' Association UK GP committee, described wider spacing of doses as "a huge gamble, and one made without the data to back this strategy".
However, Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene and Tropical Medicine, told the Science Media Centre (SMC) that "it is simply not true to say that there is evidence that using the vaccines in a different way will have dramatically reduced efficacy". He added: "We have some evidence that the efficacy is quite good, and there are no reasons to believe it will show a sudden decline between 3 and 12 weeks.
"We must take into account that in the current UK context there will be many more cases of disease and therefore more deaths by vaccinating fewer people."
Writing in The Mail on Sunday, Prof Jonathan Van-Tam, England's deputy chief medical officer, explained: "If a family has two elderly grandparents and there are two vaccines available, it is better to give both 89% protection than to give one 95% protection with two quick doses, and the other grandparent no protection at all."
The Academy of Medical Royal Colleges and Faculties in Scotland said it was "essential that the number of people who have been vaccinated with at least one dose of either vaccine is increased as quickly as possible".
'Confusion' Over School Reopening in England
Teaching unions called for schools to remain closed to most pupils because of high infection rates from SARS-CoV-2.
It came after the Scottish Government ordered schools to shut until at least the beginning of February.
The NASUWT accused the Government at Westminster of a "chaotic" handling of the reopening of schools after the Christmas break which it said posed a serious risk to the health of education sector workers, and could fuel the pandemic.
All of London's primary schools, as well as some in surrounding areas of South East England, have been closed until January 18. However, primary school children elsewhere have been told to return to classes.
The National Education Union called for all primary schools to move to remote learning for the first two weeks of January to protect its members from the risk of infection
Secondary schools are introducing a phased return, pending the introduction of lateral flow tests for pupils.
Lawrence Young, a virologist at the University of Warwick, said latest research indicated that the spread of the new variant of SARS-CoV-2 "may have been driven by schools remaining open".
Frances O'Grady, TUC General Secretary, commented: "The Government's own advice from SAGE makes it clear that opening schools to all pupils now risks increasing the infection rate. That's in no-one's interests.
"Instead of creating chaos for parents and exposing workers to risks, the Prime Minister should be talking to trade unions about what steps are needed to make sure all schools are COVID-secure."
Speaking earlier, Boris Johnson insisted that "closing primary schools is I think for all of us a last resort".
Scientists Concerned Whether Vaccines Will Work Against South Africa Variant
Tests are underway to establish whether existing COVID-19 vaccines will work against the South African variant of SARS-CoV-2.
The South African variant, 501.V2, is more infectious than the original virus.
Prof Francois Balloux, director of the UCL Genetics Institute at University College London, told the SMC: "The E484K mutation has been shown to reduce antibody recognition. As such, it helps the virus SARS-CoV-2 to bypass immune protection provided by prior infection or vaccination.
"It is not anticipated that this mutation is sufficient for the 'South African' variant to bypass the protection provided by current vaccines. It's possible that new variants will affect the efficacy of the COVID vaccines, but we shouldn’t make that assumption yet about the South African one."
Prof James Naismith, Director of the Rosalind Franklin Institute, and University of Oxford, said: "Viruses mutate and new strains will emerge. The so-called South African strain has a number of changes, and scientists are working flat out to understand their significance. Some of the changes are quite significant and thus scientists are paying a lot of attention. We do not yet know enough to say more than this.
"For the general public, I would say think about our human nature. Many of us like a good scare and horror stories are part and parcel of human culture, which means such things get a lot of coverage. However, a drumbeat of nightmare scenarios about this new variant does nothing but create anxiety because too little is known and there is nothing we can do about it at the moment."
Pandemic Public Health Concerns
Public health experts have called on people in the UK to improve their health and lifestyle habits in the wake of surveys suggesting that COVID-19 and months of lockdowns have impacted on population health.
Public Health England (PHE) said that since the pandemic began:
35% of people reported snacking on unhealthy food and drink at least once a day
29% of smokers said they smoked more since the second national lockdown
23% of drinkers said they were consuming more alcohol
PHE said that an England-wide survey of over 5000 adults found that 80% of adults wanted to make changes to their lifestyle in 2021, with 68% saying that they were motivated to make healthier lifestyle changes due to the pandemic.
Dr Alison Tedstone, chief nutritionist at PHE, said: "The past year has been immensely challenging and being stuck at home much more this year, understandably, has seen some unhealthy habits creeping up on us all.
"But our survey shows the vast majority of us want to do something positive this year to improve our health and now is a good time for a reset."