Teachers have demanded to see more evidence the government has used to underpin its decision to reopen schools, following key talks with scientific experts this afternoon.

The NEU teaching union has said “very many questions that we asked were not addressed in the time available”, including why England “seems alone in saying that social distancing is not necessary in schools”.

And the NASUWT teachers’ union said the meeting with government experts “raised more questions than it answers.”

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NASUWT general secretary Patrick Roach said: “Today’s meeting has raised more questions than answers.

“No information was provided to change the widely held view that the evidence base for opening schools from 1 June is weak.

“No evidence was provided at the meeting and there was no clarity about when it will be provided by SAGE.

“No confirmation was provided that teachers are at low risk of catching the virus following the wider opening of schools.

“No clear information was provided on what modelling has been undertaken in relation to potential transmission rates when schools open more widely.

 “Nothing in the meeting provided reassurance for the deeply worried and anxious school workforce.

 “We are continuing to press for answers to these questions and also for clear guidance from Government to schools to ensure that they take appropriate and reasonable steps to assess and mitigate the health and safety risks posed by COVID -19.

“The NASUWT remains clear that no school should reopen until it can demonstrate that it is safe to do so,” he added.

Kevin Courtney, NEU joint general secretary, also said unions were told that there are cases where children do act as the index case - meaning they are the first documented patient in an outbreak.

His union has now written to the scientific panel with its urgent questions, including:

• How they will know the effect on the R rate of the current lifting of lockdown before further steps are taken?
• What are the conditions that need to have been achieved before any wider opening of schools, eg, is there a particular daily case count that they are hoping for?
• Why our country seems alone in saying that social distancing is not necessary in schools? We were not presented with any scientific evidence to justify the decision not to include social distancing in the guidance to English schools whereas it is an important part of the guidance in other countries, in fact, we were told that they have evidence that children have passed the disease to adults.

Mr Courtney said: “We are pleased with today’s engagement, but very many questions that we asked were not addressed in the time available.

“We think it is very important that all the questions are answered and in public written form. This is important for transparency and for other scientists to comment on.

“We are pleased that Sir Patrick Vallance told the National Education Union that information and papers from SAGE would be published and that they will prioritise its release.

“We have also asked to see any commentaries or papers produced by Public Health England that comment on the Department for Education’s guidance.

“We were told that we are in the foothills of knowledge and there is still a lot of uncertainty about the science, for example, we were told children’s likelihood to transmit Covid-19 is not more than adults but only that it may be less than adults.

“Just yesterday, the Office of National Statistics suggested that age does not affect the likelihood of being infected. Today we heard that there are cases where children do act as the index case.”

Meanwhile, the Association of School and College Unions general secretary Geoff Barton also said his union was seeking further answers.

“We are asking questions about the science which underpins [the government’s] approach on behalf of our members, their staff, parents and pupils.

It is vital that school communities have confidence that it is safe to return. We continue to work constructively with government to this end.”