The largest education union in Europe has written to the Prime Minister asking for full disclosure over his decision not to shut schools amid the coronavirus pandemic.
Teachers and staff are increasingly asking why the Government is not closing schools in the same way as other countries, particularly now plans are under way to ban mass gatherings, the letter from the National Education Union says.
Boris Johnson said on Thursday closures now could do "more harm than good", hours after Ireland announced schools and colleges would close for a fortnight.
The letter from the NEU to Mr Johnson says: "We all want to limit and delay the spread of the coronavirus and we do think medical advice and expert scientific advice is important in this regard.
"But it is clear that such advice can have uncertainties, and that it could be crafted to target a variety of measures."
The letter continues: "We now see that you may take legal powers to force schools to remain open even when heads and teachers think there is good reason to close.
"In those circumstances we, as the leaders of the largest education union, believe that it is right for us to ask you for fuller disclosure of the models you have looked at, and to understand which measures you are targeting.
"We do not have the medical expertise to know what the transmissibility is between children and staff in close quarters in classrooms – but your scientists will have made assumptions about that, together with some view of the certainty of those figures.
"It is very important that we understand what the increased rate of infection is for staff and parents if schools remain open, including obviously for those with underlying health conditions themselves, or for those they care for."
The letter, from the union’s joint general secretaries Mary Bousted and Kevin Courtney, adds: "We know you’ve expressed concerns about children not in school being cared for by vulnerable elderly grandparents, or by NHS staff who would then not be available for work.
"However, we would suggest that parents and schools would be able to work together to find solutions to that - and we would like to know if you have any modelling of such societal responses.
"Most of all we think that education staff deserve to have access to modelling of the projected spread of the virus and the projected number of fatalities in a wide variety of scenarios including in scenarios where schools are closed for different periods of time.
"Teachers and other staff would work to help a broader societal response to mitigate the effects of the virus. We know this is especially important in a country where public services and the NHS in particular have been run down for so long.
"However it is vital that you share all of the potential models you have with us if that societal response is to be as strong as possible."
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