A national incident was declared by UK health chiefs today after it emerged that polio could be spreading in the community once more.
The disease – thought to be resigned to history – has been spotted in sewage samples in parts of London.
It is an evolved version of a weakened form of the virus found in live attenuated vaccines, which use a modified piece of the virus.
But there are signs it is spreading between people as officials have picked up several samples from different people, each with new mutations.
Here is everything you need to know about the UK polio situation so far:
The polio vaccine is given at age eight, 12 and 16 weeks as part of the six-in-one vaccine and then again at three years as part of a pre-school booster. The final course is given at age 14. The World Health Organization has set the threshold of a successful school jabs programme at 95 per cent uptake, which England is failing to hit by all accounts
Parents are being urged to ensure their…