Experts have warned that it is “highly likely” there will be large levels of coronavirus infection in schools by the end of September.
Advisers have told the Government to plan for this outcome, and said it remains uncertain as to whether the high prevalence might be as a result of spread of the virus within schools or in the community.
In a newly published document from the Scientific Pandemic Influenza Group on Modelling, Operational sub-group (SPI-M-O), experts said the vaccine rollout – which currently extends only to 16-year-olds and above – will have made “almost no difference” to many pupils.
Currently only 12 to 15-year-olds who are most at risk from Covid or who live with people at-risk are eligible to be jabbed.
In light of the warning, the leader of the largest teaching union in the UK has called on the Education Secretary to support schools to “consider face coverings from day one of term” alongside social distancing where possible.
Meanwhile, the school leaders’ union has called the document “extremely worrying”, adding that the situation is “on a knife edge” as term approaches.
The experts say it is highly likely there will be exponential increases of the virus in school-aged children after classes return, and note that measures in place before the new term, such as bubbles and stricter rules on isolating, will no longer apply.
The document, dated August 11, states: “Schools will represent a high proportion of remaining susceptible individuals and it is highly likely that exponential increases will be seen in school-attending age groups after schools open.
“Vaccination will also have made almost no difference in these population groups over the summer holidays.
“When schools reopen, the mitigations in place to limit transmission within schools will be much reduced compared to the spring and summer terms.
“Additionally, the prevalence of infection in the community and school-age groups will be higher than in May 2021.”
The latest estimates from the Office for National Statistics show infection levels across all four UK nations have risen.
A rise in cases in Scotland has already been attributed partly to schools returning this month.
Pupils began returning to school in Leicestershire this week, with most pupils in England, Wales and Northern Ireland set to head back to class over the next fortnight.
The document adds: “It is highly likely that high prevalence will be seen within schools by the end of September 2021.
“This may reflect either community or within-school transmission, and the role of schools in driving wider transmission remains uncertain.
“Regardless of this, it would be sensible for government to plan for this eventuality.”
Earlier this week the Department for Education announced that returning secondary school pupils in England are being urged to get tested – and vaccinated where possible – to stop coronavirus spreading and minimise disruption to lessons.
Schools and colleges in England are also being encouraged to maintain increased hygiene and ventilation from September, but year group “bubbles” and face covering requirements have been removed.
Unions have called for more action to ensure schools are kept as safe as possible and education is not disrupted further.
Kevin Courtney, joint general secretary of the National Education Union (NEU), said current safety requirements are “not sufficient” to prevent a rise in cases.
He said: “Next to nothing has been done to prepare for the possibility of large numbers of cases which will lead to lots of education disruption as children and staff have to isolate because they are positive – or stay off because their Covid symptoms go on longer.
“It is only right to recognise that a large percentage of the school community is unvaccinated, and that this will remain the case for a while yet.
“We cannot just assume a return to normal from the start of term. The bringing together of a school community of several million will inevitably lead to a rise in case counts.”
Mr Courtney added: “To prevent a sharp rise in cases, the watchwords must be ventilation, air filtration, masks, vaccines and vigilance.
“Gavin Williamson needs to support schools to consider face coverings from day one of term, alongside social distancing where possible, and special consideration for vulnerable staff.
“The danger is not that schools and colleges will be slow to act, but that Government is.”
Julie McCulloch, director of policy at the Association of School and College Leaders (ASCL), said: “It is extremely worrying to see scientific advisers concluding that exponential increases of coronavirus infections are highly likely in school-age children and demonstrates that the situation is on a knife edge as the new term approaches.”
She added: “The Government has published a contingency framework which maps out a series of measures in response to outbreaks of coronavirus. But there is a real danger that this will become the normal state of affairs with various measures being implemented on a local basis.
“This is clearly a recipe for chaos, and the Government cannot once again allow a situation to develop in which attendance unravels, and children experience yet more disruption.
“It would also be helpful to hear from the JCVI sooner rather than later about the possibility of offering vaccinations to 12 to 15-year-olds.”
A Department for Education (DfE) spokeswoman said: “Education remains a national priority, and the plans for autumn will make sure schools and colleges deliver high-quality, face-to-face education to all pupils with minimal disruption. We know that being out of education causes significant harm to educational attainment, life chances, mental and physical health.
“Thanks to the success of the vaccine programme, we are able to return closer to a normal education experience for the autumn term.
“The measures in place strike the right balance between making schools safe with enhanced ventilation, Covid testing and vaccinations of older students and staff, and reducing disruption by removing bubbles and face coverings.”