A town in Greater Manchester has seen thousands of children forced to miss school after being hit hard by the Delta coronavirus variant, which was first identified in India.
As many as one in four state school pupils in Bolton were absent on 27 May after testing positive for COVID or coming into contact with someone who had, data shows.
The figures, released on Tuesday, come as the government considers whether its plans to reopen society on 21 June will need to be delayed following a recent rise in infections.
Younger people are the main driver in the increase, with recent data showing 10- to 19-year-olds have higher infection rates than any other age group.
The government has been increasingly criticised for relaxing restrictions in schools in mid-May, with some experts calling for the return of non-pharmaceutical interventions in classrooms, such as face masks and better ventilation.
Health secretary Matt Hancock has also been criticised for ignoring questions about why ministers removed the face mask mandate.
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Independent Sage member Dr Zubaida Haque said the government has left local authorities to step in to introduce mitigating measures.
She wrote: “Has Gavin Williamson abdicated all responsibility for the health and wellbeing of children & school populations?
“It is astonishing that once again local authorities & schools are having to step in (with #facemasks) in the absence of government leadership.”
In Bolton the issue of children missing school is stark.
The upper estimate for the proportion of pupils who were unable to attend school because of COVID related reasons on 27 May was 25.9%, according to the latest statistics from the Department for Education.
On that date, 21% of primary pupils and 31% of secondary pupils were off school.
This amounts to a total of 8,575 pupils in the city altogether.
The UK has seen a big increase in state school students isolating because of coming into contact with a case in school, up 51% in a week to 90,200 as of 27 May – as shown in green on the graph above.
State school students absent due to confirmed cases also rose to 4,500 – shown in yellow.
Altogether, students who were unable to attend school for COVID-related reasons across the UK rose by 35% to 139,400.
The figures come amid concerns that the Delta variant of the virus could affect children more severely.
Meanwhile, the government has faced criticism for removing mask requirements from schools as the strain spreads across the UK.
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