A Dundee school has been forced to close for the rest of the week after six positive Covid-19 cases were confirmed.
Kingspark School has also been shut down and sealed off for two days to allow a deep clean to be carried out.
Staff and pupils at the additional support needs school were sent home on Wednesday afternoon after news of an outbreak first emerged the day before.
NHS Tayside and Dundee City Council confirmed an adult connected to the school had tested positive for the deadly virus after falling ill over the weekend, after parents were notified of a case linked to the school.
Dr Mike Lonergan, senior statistician and epidemiologist at Dundee University, said it was not surprising that there had been fresh confirmed cases linked to schools since term began.
He said: “At the start saying it can’t be transmitted in schools was too strong and saying it doesn’t affect children was too strong.
“But the only way to know if something has been done wrong is if the school reopens and things start to spread, but if it is kept shut we will never know if closure was necessary or not.”
Despite the closure, he said he thought mid-August was the right time for the schools to go back, and suggested they could even have returned earlier.
He added: “Some things are more important than others and it is worth having continuous restrictions on other things to keep the schools going.
“However Wednesday would be quite quick for people to test positive if they caught it at school.
“They’d probably have had to have caught Covid-19 almost as soon as the school reopened, so maybe it wasn’t actually passed on at school but through contacts between those people outside school.”
Dr Ellie Hothersall, consultant in public health medicine at NHS Tayside, said the closure was a “precaution” given the “varied needs” of pupils who attend.
Meanwhile Paul Clancy, executive director of children and families service at the council, said a deep clean was essential to ensure any trace of the virus was eradicated.
He added: “There are robust hygiene measures and other mitigations in place throughout Kingspark School, however, given the vulnerabilities and complex needs of the pupils, we cannot take any risks.
“This has been a difficult decision to reach, but it is one I hope that families can understand and appreciate.
“Safety has to be paramount.”
A decision will now be taken on Monday on whether or not the school should reopen.
Meanwhile the health board said no new cases had been reported in connection with two Perthshire pupils who had also tested positive for Covid-19.
The two children, who attend Oakbank Primary School in Perth and Newhill Primary School in Blairgowrie, are currently self-isolating at home with their families and are said to be displaying mild symptoms.