More than 40 children were sent home from a school in Huntingdon after a child tested positive for Covid-19.
Forty-one children and some members of staff from Spring Common Academy who were in the same learning “bubble” are now self-isolating.
Parents were informed on Wednesday (September 16).
The group were part of an early years and key stage one bubble at the school in American Lane.
A Cambridgeshire County Council spokesperson said: “We can confirm we have been notified of a positive Covid-19 test result at Spring Common Academy.
“The affected person is isolating, and those within the same bubble are not at school, as per the existing process agreed by the local authority, Public Health England and our schools.
“We are working with the school and it remains open and safe for all other children and staff”.
The self-isolation period began on September 10, and staff and pupils will be allowed to return to the school on Friday, September 25 provided they have been free of symptoms for 48 hours.
Spring Common is a state-funded school for children aged 3 to 19 with special needs.