What is known about how the virus is transmitted among children and what could allow schools to reopen?

What’s the risk to children and young people?

Children’s risk of becoming seriously ill from the virus is tiny. This hasn’t changed even with a new, more contagious variant of coronavirus circulating.

Despite a rise in the number of children infected, child health experts are not seeing a substantial rise in Covid-related illnesses in children in hospital.

“As cases in the community rise there will be a small increase in the number of children we see with Covid-19, but the overwhelming majority of children and young people have no symptoms or very mild illness only,” says Prof Russell Viner, president of Royal College of Paediatrics and Child Health.

And Dr Mike Tildesley, an infectious disease modeller, said “we are not getting a significant increase in cases in a primary school setting despite this new variant”.

One in three people are thought to have no symptoms when infected with the virus. This appears to be the case among children at least as often as adults.

Do children spread the virus?

Among pupils in primary schools, evidence shows that there is limited spread of coronavirus.

Children of secondary school age are different, however - they appear to be more able to pass the virus on.

There is no evidence that teenagers are more likely to transmit than adults.

But school children and young adults have undoubtedly experienced a much faster rise in infections than other age groups in the second wave - and that may be down to their opportunities to mingle.

During England’s lockdown in November, for example, schools remained open and operated normally, while many other areas of society were nowhere near normal levels of mixing.

What role do schools play in spreading coronavirus?

This is difficult to unpick. When schools are open, there is more spread among school children, particularly those of secondary school age. There have also been signs that transmission dips after school holidays, such as half term.

But are levels of infection in schools simply reflecting levels of the virus in their local communities?

Early data from an ONS survey of 100 schools in England, which tested random pupils and staff without symptoms, suggests this is the case. It found 1.24% of pupils and 1.29% of staff tested positive for the infection in November, mirroring an estimated 1.2% infection rate in the general population.

And Jenny Harries, England’s deputy chief medical officer, recently said schools were “not a significant driver” of cases of Covid in communities, although she said children could definitely transmit the infection in schools and elsewhere.

Sage, the government’s scientific advisory group, recognises the challenge of judging the role of transmission in schools.

“It is difficult to quantify the size of this effect and it remains difficult to quantify the level of transmission taking place specifically within schools compared to other settings,” they reported in December.

What’s the risk to teachers?

Secondary school teachers have a slightly increased risk of dying - 39 deaths per 100,000 people for men and 21 per 100,000 for women, compared to rates of 31 and 17 in the population as a whole.

Nurses, cleaners, social workers, restaurant staff, taxi drivers and security workers are all at greater risk than teachers, according to the Office for National Statistics.

But that doesn’t tell the whole story, of course - your ethnic background, underlying health conditions, where you live and who you live with are all factors too.

There is no doubt teaching staff work in busy and crowded workplaces, leading teaching unions to call for vaccines to be prioritised for staff in schools.

They could be added to the vaccination programme after the over-50s, along with police officers and supermarket workers.

Will closing schools have an effect?

Since the first national lockdown in spring 2020, keeping schools open has been a priority.

The advisory group Sage has always said that closing schools - in particular secondary schools - was likely to have an impact on the “R” or reproduction number of the virus, bringing it down slightly.

And Education Secretary Gavin Williamson has said there is early evidence from Sage that the closure of primary schools is likely to have a greater effect than the closure of nurseries.

But the longer-term question is how long they could reasonably be closed for and what would happen when they opened again.

Dr Shamez Ladhani, the chief investigator of the ONS schools survey and a consultant at Public Health England, says driving down infections in wider society is the best way to keep schools open and safe. He said closing them would only have a temporary effect on cases.

But Sage also says policymakers need to weigh up the benefits and harms of closing schools. This includes reducing the direct health risks to staff and the negative impact on children’s mental health, education, development and wellbeing.

Many experts agree this is a difficult balancing act and argue schools should be the last things to close and the first things to open up again.

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BBC

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