Schoolchildren across the UK are returning to classrooms amid concerns about a lack of staff as more than a million people in Britain are estimated to be isolating because of the coronavirus. With projections of up to a quarter of school staff members having to isolate at home in January, some schools could be forced to send children home if there are not enough teachers available. New rules mean <a href="https://www.thenationalnews.com/coronavirus/2022/01/02/masks-return-to-english-secondary-schools-in-bid-to-curb-omicron-spread/" target="_blank">secondary school pupils will be required to wear masks while on school premises. </a> Prof Neil Ferguson, a leading epidemiologist at Imperial College London whose modelling was instrumental in the government’s decision to impose the first lockdown, said the reopening of schools risked sparking a surge in infections. He said the <a href="https://www.thenationalnews.com/coronavirus/2022/01/03/covid-19-what-are-the-symptoms-of-the-omicron-variant/" target="_blank">Omicron variant,</a> which was first detected in the UK in November, did not have enough time to “get into schoolchildren before schools shut” for the Christmas and New Year holidays. “We expect to now see quite high infection levels of mild infection, I should emphasise, in school-age children,” he told BBC Radio 4’s <i>Today </i>programme. Mary Bousted, joint general secretary of the National Education Union (NEU), said the impact of staff shortages on the schooling system “could be significant”. She said 8 per cent of education staff were absent in December when a mix of Delta and Omicron infections were in circulation. The figure is likely to rise if Omicron continues to spread rapidly. Dr Bousted pointed to data from the Office for National Statistics which said education staff were 37 per cent more likely to contract Covid-19 than any other profession. “So if they do that [contract Covid] and they have to be at home, then there will be the issue of who will be taking classes,” Dr Bousted told <i>Sky News.</i> “That’s a real problem because we know the one thing that we want to happen is for schools to be open and children and young people to be educated in school because that’s the best place for them. “So it is a shame that the government hasn’t done more to ensure that that is going to happen.” She backed the new mask rule for secondary school pupils in England, saying “the mental-health effects of not being in school are far greater than wearing a mask”. She said mandatory masks were a fair price to pay for keeping children in school. “If wearing a mask is a price to pay for staying in school, continuing to be educated, continuing to be learning with your friends, continuing to socialise, continuing to have a place to go, if you’ve got free school meals continuing to get those free school meals, if you’ve got worries and troubles in your life having a school that is a place where you’ve got people to talk to, who will be able to help you. All the benefits of being in school and schools remaining open are far greater than the disadvantage of wearing a mask. The two just don’t compute.” Prof Ferguson said he was “cautiously optimistic” that infection rates in London in the 18-50 age group may have plateaued. But he said hospital admission numbers could be driven up in the coming weeks if Omicron makes its way into older members of the population. He pointed to figures showing that Covid-related hospital admissions have doubled in the past two weeks, but acknowledged the numbers were well below those seen during the height of the pandemic last winter. “That is good news and it shows that vaccination is holding up in terms of protection against severe disease, assisted by the fact that Omicron almost certainly is substantially less severe,” he said. “But it still puts pressure on the health system.” He said given the rapid spread of the Omicron epidemic across the UK and the huge numbers of infections it resulted in, case numbers should start to stabilise and come down over the next one to three weeks. He said data showed case numbers in London were already reducing. “Whether they then drop precipitously or we see a pattern like we saw with Delta back in July of an initial drop and then quite a high plateau, remains to be seen,” he said. “It’s just too difficult to interpret current mixing trends and what the effect of opening schools again will be.” Prime minister Boris Johnson will chair a cabinet meeting on Tuesday to discuss the path forward in the fight against the virus. Vaccines minister Maggie Throup declined to say how many people were isolating but reports suggest the number is about a million. “I’m not sure of that [actual] figure, but I think what’s shown over Christmas is that a lot of people have caught the disease, the Omicron variant is very transmissible, but what is good news, it doesn’t seem to be resulting in severe diseases as some of the other variants did,” she told Sky News. “Well, not everybody declares that they’re self-isolating, I think that’s one important thing, that it’s something that they do because they’ve tested positive or they’ve been in contact with somebody who's tested positive, they don’t have to report that. “The vaccine is working and that’s the best way to stop the transmission, and to stop hospitalisations and for our life to get back to normal.” She insisted Plan B restrictions in place to restrict the virus would suffice in the current battle against Covid, saying, “I don’t see the reason why we need to change”. “It’s important that we do follow the data, we’ve done that all along and will continue to do that, and people are playing their part and I want to thank them for that,” she said. Six NHS trusts have declared critical incidents, according to reports, as the National Health Service threatens to buckle under the strain of the latest variant.<a href="https://www.thenationalnews.com/coronavirus/2022/01/03/uks-omicron-surge-causes-hospital-staff-shortages/" target="_blank"> Staff and bed shortages are contributing to the crisis in hospitals</a>. Ms Throup declined to say exactly how many trusts had brought in additional measures because of the pressures. Latest data shows fewer Covid-19 patients requiring ventilators compared with previous waves of the virus. Chris Hopson, chief executive of NHS Providers, which represents acute, ambulance, community and mental health services, said the emergency measures are designed to ensure essential services can still be provided to patients in the midst of a crisis. “If you declare a critical incident it means that you are under very significant pressure but there is a very good reason as to why you call a critical incident and that is first of all you are able to get help,” he told Sky News. “So, in other words, you flag to your staff that actually we really need people to come in and work extra shifts if at all possible. “It means you can get help from the neighbours; so if you’re a hospital trust you can say to the ambulance trust, look in extremis could you please convey patients to the neighbouring hospital as opposed to ours.” Tuesday marked a year since the first AstraZeneca vaccine was administered in the UK. Since then more than 50 million doses have been given to people across the country and 2.5 billion shots around the world.