Children with mild and moderate anxiety are likely to be better off attending school because long periods of absence can make symptoms worse, the chief medical officer for England has said.

Amid mounting concern in government about the crisis in pupil attendance since Covid, Prof Chris Whitty has written to schools to reassure parents that anxiety can be a normal part of growing up and that being in lessons can help.

As the new school term got under way across England, Whitty said it was also appropriate for parents to send children to school with mild respiratory illnesses, including cold symptoms such as a minor cough, runny nose or sore throat. He said they should not be sent to school if they had a temperature of 38C or above.

Details of the letter emerged as the government’s preferred candidate to take over as Ofsted’s chief inspector of schools and children’s services in England called for an urgent review of increased absence in schools since Covid.

Sir Martyn Oliver, the chief executive of the Outwood Grange academies trust (OGAT), said this week’s hot weather and “some of the issues we are reading in the news” – taken to mean the Raac crisis in school buildings – were likely to further dent attendance.

Giving evidence to a pre-appointment hearing of the Commons education committee, he said: “Right now I desperately need Ofsted to do a thematic dive into attendance – right now.” He added: “It’s too late.”

According to headteachers, anxiety is one of the key reasons behind increased pupil absence. Whitty’s letter, which was also signed by other health leaders, is intended to help parents assess whether their child is well enough to be in school.

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