The government has specified for the first time that schools may be required to shut if staff shortages lead to “operational issues”. 

In an updated, more concise document, the Department for Education (DfE) has issued more detail on the circumstances of individual school closures.

However, it has still not given any further indication as to when mass closures could be enforced.

Boris Johnson said last week that the government will not be closing schools in the UK as a result of the coronavirus outbreak, but the decision may change as the disease spreads.

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Previously, the guidance said: “In most cases, closure of the childcare or educational setting will be unnecessary but this will be a local decision based on various factors such as establishment size and pupil mixing.”

It has now added: “If there is an urgent public health action to take, the educational setting will be contacted by the local Public Health England (PHE) health protection team, who will undertake a risk assessment and advise on any actions or precautions that should be taken.

“PHE will rarely advise a school to close but this may be necessary if there are so many staff being isolated that the school has operational issues. Your local authority will support you to make this assessment.

“PHE will work with the headteacher, principal or management team, and the local authority public health team, to advise on the management of children, pupils, students or staff.”

Headteachers have reported today that some parents are unilaterally taking their children out of school with attendances as low as 55 per cent.

The government has cut the overall length of its Covid-19 guidance for schools by more than two-thirds.

Previously, the DfE guidance comprised 14 sections and 2,938 words.

It has now been reduced to a far more concise document, less than a third of that length (778 words).

The new guidance condenses “what you need to know” into six key bullet points:

• Staff, young people and children should stay at home if they are unwell with a new, continuous cough or a high temperature to avoid spreading infection to others. Otherwise they should attend education or work as normal.
• If staff, young people or children become unwell on site with a new, continuous cough or a high temperature, they should be sent home.
• Clean and disinfect regularly touched objects and surfaces more often than usual using your standard cleaning products.
• Supervise young children to ensure they wash their hands for 20 seconds more often than usual with soap and water or hand sanitiser, and catch coughs and sneezes in tissues.
• Posters and lesson plans on general hand hygiene can be found on the eBug website.
• Unless you have been directly advised to close by the local Public Health England health protection team, we recommend all education settings remain open.

According to the guidance, if pupils become unwell at school, they should be isolated while they wait for their parents to collect them - ideally in a room behind a closed door, with a window open.

If this is not possible, then pupils should be moved to an area which is at least 2m away from other people, while separate bathrooms should be used.

For any staff dealing with suspected cases of coronavirus, the guidance says they do not need to go home unless they develop symptoms themselves, but adds they should wash their hands thoroughly for 20 seconds afterwards.

Education secretary Gavin Williamson is due to meet school leaders today to discuss the implications of widespread school closures amid the coronavirus pandemic.

The meeting comes after teachers questioned why the government is not closing schools in the same way as other countries.

The DfE says the guidance, which covers childcare, schools, further and higher educational institutions, may be further updated in line with the changing situation.