Unvaccinated children face being forced to self-isolate for 21 days because of a rapid rise in measles cases.

Councils issued warnings to parents after modelling suggested that up to 160,000 cases could occur in London alone. Health officials say low uptake of MMR jabs has increased the risk of the potentially deadly infection.

In letters from local authorities, parents in London and its surrounding counties were told that if a pupil is infected, classmates who have not had both doses of MMR could be sent home and asked to self-isolate for three weeks.

Uptake of the jabs fell significantly in the years following the discredited Andrew Wakefield study, which falsely linked them with autism in 1998.

It increased sharply after concerted efforts to persuade parents of the benefits of vaccination but has fallen again in recent years, with the programme set back during the Covid crisis.

Children at risk have already missed months of teaching during the pandemic because of school closures and being asked to self-isolate.