A new study will conclude there is "very little evidence" that coronavirus is transmitted in schools, a Sage member has said.
The Public Health England research, carried out in around 100 schools in England, monitored the spread of the disease as schools partially reopened in the summer term.
It will find there is "very little evidence that the virus is transmitted in schools", according to Professor Russell Viner, president of the Royal College of Paediatrics and Child Health and a member of the government advisory group Sage.
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And a separate review of 35 studies from around the world, due to be published next month, will also conclude children and schools play only a "minor role" in spreading the virus, Professor Viner said.
The leading scientist told The Sunday Times: "A new study that has been done in UK schools confirms there is very little evidence that the virus is transmitted in schools.
"This is...some of the largest data you will find on schools anywhere. Britain has done very well in terms of thinking of collecting data in schools."
He added that, if test and trace systems are not up to scratch by September, schools should take priority over pubs, clubs, some shops and businesses "not essential to the future of society" when thinking about what might need to close.
"It is absolutely essential for schools to reopen in September. The risks to children from Covid are very low and the risks of school closures we know are very serious," he said.
"Britain as a nation should stand up and say: our children are essential. Reopening schools is essential.
"If we do not feel test and trace is fully in place by September, we need to look carefully at the level of R [rating the virus' ability to spread] at that point and look at what trade-offs may be necessary.
"That is when I would be very clear that schools need to be open before pubs and clubs."
Professor Viner also suggested a separate study by his team will find children and schools play only a "minor part" in Covid-19 transmission, as staff suffer the bulk of the cases.
"Everything you do to reopen society will impact the national R, but reopening schools, we believe, has a very small impact on it. The majority of cases are staff, not students," he said.