Schools are in a “precarious” situation over Covid outbreaks and data needs to be made “readily available” so cases can be “monitored carefully after half-term”, a headteachers’ leader has warned.

Geoff Barton, general secretary of the Association of School and Colleges leaders, was commenting after new data from Public Health England showed a rise in school outbreaks linked to the Delta variant of Covid (previously known as the Indian variant).

The data showed that there were 97 confirmed outbreaks in primary and secondary schools that have had at least one variant case linked to them over the most recent four-week period, representing around 1 in 250 schools.

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“The situation clearly continues to be precarious, and will need to be monitored very carefully after the half-term holiday,” Mr Barton said.

“It is essential that data is more readily available in the future.”

‘Particular concern’ about Covid variant in schools

PHE data from the weekly surveillance report shows that Covid rates are highest in those aged 10-19. 

And in the same report, data from Test and Trace shows that the most commonly reported activity by people testing positive - by far - was attending education settings.

Mr Barton added: “Any increase of Covid cases is obviously worrying, and there is particular concern about the infectivity of the Delta variant.

“We understand the reassurance given by Public Health England that Covid outbreaks have remained low in schools and among children following full reopening in March, and full credit must go to schools and colleges for their tireless efforts in managing safety measures.

“However, we remain concerned about the length of time that it has taken to obtain data about the impact of variant strains in education settings, and about early evidence which suggests that there may be an increased risk of hospitalisation for the Delta strain.”

But PHE’s reassurances about how school outbreaks have remained low have been criticised on Twitter.

UCL’s Professor Christina Pagel tweeted: “We can see rapid growth - yes, mirroring rapid spread of Delta variant - in school outbreaks. This does not make it OK.”

Here are cases in 4 regions - all showing highest rates in secondary school children - and increasing and moving up to adults over time too. https://t.co/nPxVsvp3sw pic.twitter.com/eatTDqyWL3

- Prof. Christina Pagel (@chrischirp) June 4, 2021

And Deepti Gurdasani, epidemiology lecturer at Queen Mary University of London, tweeted: “I’m sorry, but I have to say this: are our public health bodies living in a parallel universe? This is literally from your own reports: secondary school children have highest infection rates across all age groups - and rising!”

I’m sorry, but I have to say this- are our public health bodies living in a parallel universe? This is literally from your own reports: secondary school children have highest infection rates across all age groups - and rising!https://t.co/CQZZcAoCeI https://t.co/MSIrHbFBDQ

- Deepti Gurdasani (@dgurdasani1) June 4, 2021

She also noted that while PHE urged caution on school outbreaks, it also tweeted that its report found that cases are highest in those aged 10-19.

Commenting on the PHE data, Paul Whiteman, general secretary of the school leaders’ union NAHT, said that the data reflects what the union’s members have been reporting.

“We have been hearing from our members that more and more schools are having to close multiple classes or ‘bubbles’, particularly in areas with higher case numbers. This latest official data release appears to support those concerns,” he said.

Mr Whiteman added: “The government must be proactive and use all the provisions of the existing contingency framework to ensure that transmission in schools is not allowed to proceed unchecked. We must not sleepwalk into further widespread disruption to education.”

And Dr Patrick Roach, general secretary of the NASUWT teaching union, warned: “The data shows that Covid cases in schools are at the highest level for six months.

“Every case in a school results in further damaging disruption to children and young people’s education.

“All decisions on essential control measures to prevent the transmission of Covid-19 in schools and colleges must continue to be led by the scientific data and advice to ensure that staff, pupils and the public are kept safe.”

A government spokeswoman said: “Attendance in schools remains high, and the data shows the steps we are taking to keep the Delta variant under control in schools are working.

“On top of robust measures in place across the country, such as increased ventilation in classrooms and keeping to small group bubbles, we have increased the availability of testing for staff, pupils and families in areas of high prevalence.

“We would encourage everyone to ensure they are continuing to test twice-weekly even if they don’t have symptoms. Testing regularly is even more important as pupils return to school after the May half-term to reduce transmission.”