Researchers are embarking on a major new project to track coronavirus infections in schools, the BBC reports.

Academics are hoping the study in Bristol schools will help them understand how pupils transmit the virus, whether they have symptoms or not.

Researchers will saliva-test 4,000 pupils and 1,000 staff from schools across the city every month for six months.

It comes as hundreds of schools across the country have sent groups of pupils home to self-isolate after positive cases were found.

Previous studies have show that children are less likely to contract coronavirus than adults and their symptoms are usually milder.

But experts do not yet fully understand their role in spreading the virus.

Prof Caroline Relton, an epidemiologist at the University of Bristol, told the BBC: "The main thrust of the study is to understand the rates of infections and to jump on them very quickly, so we're giving heads the tools to spot infections early and to keep their schools open, and so permit the continuity of education."