Children are not superspreaders of Covid-19 and they can return to school as they pose a low risk, research suggests.
There is limited evidence of coronavirus transmission in school settings, say experts from Dublin's Health Service Executive.
They found that nobody with the virus transmitted it to anyone else in a school setting prior to the lockdown.
The researchers traced 1,000 close contacts of three children and three teachers from the Republic of Ireland who were later found to be infected with the virus before schools were shut.
In a reception classroom, children sit apart from each other on a carpet where crosses have been marked out for them to sit on
They contracted the virus not in the classroom but when travelling or due to a household outbreak. The youngsters were all aged ten to 15 – with one in primary school and two in secondary school.
Even 'high risk' activities such as choir practice and playing woodwind instruments failed to cause a single transmitted case.
Children are typically superspreaders of viruses but experts from the HSE believe that this is not the case with Covid-19.
One single child with Covid-19 accounted for more than 500 contacts but they did not transmit the virus to a single person.
Among the three teachers, there were two secondary cases but these transmissions did not occur at a school and did not involve anyone from the schools.
There was no transmission from the adults to any children.
More than two million pupils from reception, year one and year six have been allowed to go back to school.
But older year groups, including those preparing for GCSEs and A-levels, have not been allowed to return yet.
Among the three teachers studied by researchers, there were two secondary cases but these transmissions did not occur at a school and did not involve anyone from the schools
Dr Geraldine Casey from the HSE said: 'The limited evidence of transmission in school settings supports the reopening of schools as part of the easing of current restrictions.'
The University of Warwick has also suggested that sending children to school is low risk and would not risk a second wave of the virus.
But this comes as new research, led by scientists at University College London who advise the Government, found that reopening schools will cause a second wave unless there are improvements to the test and trace system.
The study warned that opening schools this summer will lead to a resurgence of the virus in December and this second wave risks being twice as deadly as the first.
The report models that opening schools fully or in phases in June or July would create a second wave which would be around 2.2 to 2.5 times larger than the first.
And reopening in September would produce a secondary wave around 1.3 times larger.
To prevent this, the researchers said half of those with symptoms need to be tested.
But currently under 2,000 of the estimated 8,000 new cases a day are tested.
And the study says at least 40 per cent of people who have come into contact with anyone who tested positive would need to be contacted and told to self-isolate.
But the contact tracing scheme has already been branded a 'shambles'.
A leaked report said that in three days virus sufferers had provided details of 4,634 people they might have infected but just 1,749 were contacted.