Primary school pupils in London are being offered catch-up polio vaccinations after warning signs of the disease were identified across the capital.

The disease was officially eradicated in the UK in 2003 after years of vaccination programmes, but poliovirus traces were found in north and east London sewage in early 2022.

An emergency vaccination-booster campaign in London last summer reached more than 370,000 children but levels are still lower than in other parts of the country, the UK Health Security Agency (UK HSA) said.