For children and young people aged 18 and under, the advice for staying at home will be 3 days. the summary guidance advises:
Adults with symptoms of respiratory infections, AND who have a high temperature or feel unwell, should try to stay at home and avoid contact with other people until they feel well enough to resume normal activities and they no longer have a high temperature.
Children and Young People who are unwell AND have a high temperature should stay at home for 3 days and avoid contact with other people. They can return to school when they no longer have a high temperature, and they are well enough to attend.
Adults with a positive COVID-19 test result should try to stay at home and avoid contact with other people for 5 days, which is when they are most infectious.