These are the latest UK coronavirus stories you need to know.
Immunity After Infection
COVID-19 infection provides 83% protection against reinfection for at least 5 months, according to the Public Health England (PHE) SIREN study of 6614 healthcare workers.
However, people may still be able to pass on the virus despite being protected themselves. The study does not include the time when the UK Kent variant of the virus was circulating widely.
Once people had antibodies, reinfections were rare with only 44 potential reinfections identified between June and November 2020.
Study lead, Professor Susan Hopkins, PHE senior medical advisor, said: "This study has given us the clearest picture to date of the nature of antibody protection against COVID-19 but it is critical people do not misunderstand these early findings.
"We now know that most of those who have had the virus, and developed antibodies, are protected from reinfection, but this is not total and we do not yet know how long protection lasts. Crucially, we believe people may still be able to pass the virus on."
The study will continue its routine screening of participants for 12 months.
Nearly 100,000 NHS staff were absent from work in England on 6 January, with almost half being COVID-19 related, latest figures show.
Deputy Chief Executive of NHS Providers, Saffron Cordery, commented: "The number of staff absences due to sickness or self-isolation is worrying. It makes the task of dealing with COVID-19, winter pressures, and a huge vaccination programme even more challenging."
Visits to England's emergency departments were 50% higher than in the April first wave peak, according to latest data. One in 4 of all patients admitted to hospital through A&E waited more than 4 hours for a bed.
There are around 13,000 more people in hospital with COVID-19 today than in April 2020.
There are a record 4.46 million patients waiting for routine treatment and operations.
More than 192,000 patients have been waiting more than a year for planned surgery.
Professor Stephen Powis, NHS England's national medical director, said: "These figures are a stark reminder that the NHS is facing an exceptionally tough challenge, and that while still millions of people are getting care for non-COVID health problems in the NHS in England – indeed for every COVID patient in hospital, the NHS is treating three people for other conditions – there is no doubt that services will continue to be under additional pressure until and unless this virus is under control."
Dr Katherine Henderson, president of the Royal College of Emergency Medicine, said: "These data are truly alarming. While attendances are still down the number of patients spending over 12 hours in the ED has skyrocketed – and these are just the tip of the iceberg. We are no longer in a crisis; this is a national emergency."
Professor Ravi Mahajan, president of the Royal College of Anaesthetists said on Thursday: "Today’s figures are a stark reminder of the enormous impact the pandemic is having on planned procedures."
Tim Gardner, senior policy fellow at the Health Foundation, commented: "NHS staff are under immense strain with existing staff shortages exacerbated by absences of nearly 100,000 who have COVID-19 or are self-isolating. In November, patient waiting lists hit a historic high of 4.46 million and this is likely to have grown since. The picture is of a system being tested to its very limits."
Siva Anandaciva, chief analyst at The King’s Fund, said on Thursday: "Today’s figures show that the NHS is now under the most extreme pressure seen in recent history and is battling on multiple fronts. Staff are exhausted, wards are overflowing and patients face long waits for routine and emergency care, with many procedures being cancelled or postponed."
On Wednesday, Prime Minister Boris Johnson was asked why a travel ban had not been put in place yet to help stop a new Brazilian variant of SARS-CoV-2 coming to the UK.
He said steps were being taken, and this afternoon Transport Secretary Grant Shapps announced a ban on arrivals from South America: Brazil, Argentina, Bolivia, Cape Verde, Chile, Colombia, Ecuador, French Guiana, Guyana, Panama, Paraguay, Peru, Suriname, Uruguay, and Venezuela.
"Travel from Portugal to the UK will also be suspended given its strong travel links with Brazil – acting as another way to reduce the risk of importing infections. However, there is an exemption for hauliers travelling from Portugal (only), to allow transport of essential goods," he tweeted.
The ban starts at 4 am on Friday and doesn't include returning UK and Irish nationals but they will still need to self-isolate.
The new variant emerged in December in Manaus, northern Brazil and was also detected in Japan.
Government Chief Scientific Adviser Sir Patrick Vallance told ITV: "There’s no evidence at all with any of these variants that it makes the disease itself more severe. So the changes that we’re seeing with the variants are largely around increased transmission."
For the Brazillian and South African variants, he said. "There’s a bit more of a risk that this might make a change to the way the immune system recognises it but we don’t know. Those experiments are underway."
Ravi Gupta, professor of microbiology at the University of Cambridge, commented via the Science Medica Centre: "The Brazilian variant has three key mutations in the Spike receptor-binding domain (RBD) that largely mirror some of the mutations we are worried about it in the South African variant, hence the concern.
"The SARS-CoV-2 RBD is one of the main targets for our immune defences and also the region targeted by vaccines and changes within this region are therefore worrisome. Vaccines are still likely to be effective as a control measure if coverage rates are high and transmission is limited as far as possible."
University of Portsmouth research published on Thursday in Experimental Physiology found temperature scanners have limited value in detecting COVID-19 with too many false negatives.
Professor Michael Tipton from Portsmouth said: “We think we can improve the identification of the presence of fever using the same kit but looking at the difference between eye and finger temperature – it’s not perfect, but it is potentially better and more reliable."
'Mortality Rises with ICU Capacity'
A preprint study found mortality rising in UK ICUs in the first wave of COVID-19 as occupancy rose.
Data came from 4032 adults in ICUs in 114 trusts in England, April-June 2020.
When ICUs reached 85% medical emergency levels, 38.4% patients died and the probability of dying was 19% higher.
When ICU capacity was lower than 45%, mortality risk decreased by 25%.
First author, PhD researcher, Harrison Wilde, University of Warwick, said: "Unfortunately the association between occupancy and mortality risk is much larger than we ever suspected and with more people than ever being admitted to full hospitals we need to act with more urgency."
Commenting via the Science Media Centre, Duncan Young, retired professor of intensive care medicine, University of Oxford, said: "The headline result suggests that as occupancy of ICU beds increases, so does the overall percentage mortality of patients admitted during the periods of high occupancy."
However, he noted other possible explanations: “The first is that during periods of high occupancy the ICUs would likely preferentially admit the patients who were sickest, with the highest risk of dying."
Another possibility, he said, was: "As mortality was reducing over time, and for the majority of the study period ICU occupancy was also falling, there would be an apparent association between occupancy and outcome."
Some community pharmacies in England joined the COVID vaccination programme with the first appointments on Thursday.
Deputy Chief Pharmaceutical Office, Dr Bruce Warner, said: "We know that people are very keen to get the vaccine but we are appealing to people not to turn up early so that we can maintain social distancing."
As of Wednesday, 2.6 million people had received a first dose, and 428,232 a second dose.
On Tuesday 207,661 first doses were delivered across the UK.
Weekly data for England show the Midlands has delivered the most jabs so far (447,329) and the East and London the lowest (236,023 and 237,524). London's Mayor Sadiq Khan said the capital isn't getting its fair share of doses.
The group EveryDoctor reported NHS Trusts and CCGs are being instructed to throw away doses of vaccine left over at the end of day instead of using them to vaccinate NHS staff with second doses.
Public Health England (PHE) surveillance data show COVID-19 case rates have declined while hospitalisations, ICU admissions, and mortality continued to increase between 4 and 10 January.
Case rates are still highest in London 864.9 per 100,000 population. Case rates have decreased elsewhere, apart from the North West, South West, and West Midlands.
Hospital admission rates for COVID-19 have increased in all regions except the North East, and London continues to have the highest with a rate of 58.19 per 100,000.
PHE Medical Director, Dr Yvonne Doyle, commented: "The rate that people are being admitted to hospital is now higher than at any point during the pandemic. We are still seeing thousands of people having to go to hospital each day. Worryingly these numbers are likely to continue to get worse before we see the benefits of our efforts to protect the NHS, which will mean more pressure for our health service than ever before."
Latest Test and Trace data show nearly 390,000 positive cases were identified 31 December to 6 January, the highest yet.
For in-person tests, 31.5% of results were received within 24 hours.
Of cases transferred for central contact tracing, 12.4% were not reached and 1% had no communication details provided.
Among the latest positive cases is Sir Andy Murray just before he was due to leave for Australia and the first big tournament of the year.
Overseas Doctors' Parents
The BMA is campaigning to allow elderly parents of overseas doctors to be allowed to come to the UK, avoiding stress and anxiety.
Indian-born GP Dr Kamal Sidhu has been in the UK since 2003 and has been unsuccessful in bringing his elderly parents to Britain.
Dr Sidhu told the BMA’s The Doctor magazine: "We are not talking about opening floodgates as the number of potential applicants is relatively small, but the benefits massively outweigh any economic argument against. The disruption to the health service due to unplanned emergency trips – the impact it has on patient safety and continuity – cannot be understated."
Lockdown didn't help air quality around the world as much as expected, according to UK-led research published in Science Advances.
Changes in levels of nitrogen dioxide, ozone, and fine particulate (PM2.5) air pollution were assessed in London, Beijing, Wuhan, Milan, Rome, Madrid, Paris, Berlin, New York, Los Angeles, and Delhi.
After weather effects were accounted for, reductions in nitrogen dioxide were smaller than expected, and ozone concentrations rose.
Lead author, Zongbo Shi, professor of atmospheric biogeochemistry, University of Birmingham, commented: "Rapid, unprecedented reduction in economic activity provided a unique opportunity to study the impact of interventions on air quality. Emission changes associated with the early lockdown restrictions led to abrupt changes in air pollutant levels but their impacts on air quality were more complex than we thought, and smaller than we expected."
Co-author Professor Roy Harrison, added: "The reduction in NO2 will be beneficial for public health - restrictions on activities, particularly traffic, brought an immediate decline in NO2 in all cities. Had similar levels of restrictions remained in place, annual average NO2 concentrations would have, in most locations, complied with WHO air quality guidelines."
A Freedom of Information request has revealed how £63,000 was spent on 42 social media influencers, like Shaughna Phillips and Josh Denzel from Love Island, to promote Test and Trace in England.
The group Full fact got the information from the Cabinet Office, which also told it: "As part of the wider communications strategy for raising essential awareness of the NHS Test and Trace service and the importance of testing for COVID-19, we have been working with key micro and macro influencers to reach young adults in a channel they regularly engage with, as we also use traditional marketing and advertorials to reach adults via print, radio and TV advertising."