A primary school has been hit by 21 coronavirus cases among its youngest pupils.
Cardiff council said 21 positive cases of Covid-19 have been confirmed at Pontprennau Primary School in the last seven days.
Three members of staff and 80 pupils from reception and nursery years have been told by Public Health Wales (PHW) to self-isolate for 10 days after they were identified as close contacts of confirmed Covid-19 cases.
Separately a further 29 pupils and two members of staff are also self-isolating at Gabalfa Primary after one positive Covid case there, the council confirmed.
A spokesman for the authority said the schools were working closely with Public Health Wales and the council as well as following all protocols and processes required.
“Contact bubbles are in place ensuring that pupils outside the relevant contact groups are able to continue to attend school as planned without further disruption to face-to-face learning," the spokesman added.
The 21 cases at Pontprennau Primary are all in the same two contact bubble groups meaning that the rest of the school is open.
Younger pupils aged three to seven years returned to school after school lockdown closures on February 22. All older primary children and those in exam years at secondaries returned on March 15.
Secondary schools are also inviting pupils not in exam years to come in for some check-in sessions before the end of term.
All children can return to school after Easter as lockdown restrictions ease slowly, the Welsh Government has said.
Schools have re-opened with new, stricter guidance on safety measures. Staff should wear masks in primaries, including in the classroom, whenever they cannot socially distance from children.
In secondary schools staff and pupils should wear masks anywhere on school premises where they cannot socially distance, including classrooms, the guidance says. Pupils aged 14 and above are being asked to take two voluntary lateral flow Covid tests a week and staff are also being offered tests.
PHW and the Welsh Government have said schools are not necessarily places of transmission and have urged parents and carers not to mingle at school gates or let their children socialise outside school.
