Health officials are investigating an unexplained rise in cases of a mysterious polio-like illness which causes paralysis of the limbs and mainly affects children.
There have been 28 cases of acute flaccid paralysis (AFP) reported in 2018 with the majority occurring since September, according to Public Health England.
Officials would usually expect fewer than 10 cases a year in England and a similar unexplained rise has also been recorded in the US this year.
PHE said the the condition mainly – but not exclusively – affects children and said the public should seek medical help “immediately” if they notice any weakness or floppiness of the limbs.
“AFP is very rare,” Dr Mary Ramsay, head of immunisations at PHE said.
“However, if you or your child develops weakness in any limb you should seek medical care immediately so that appropriate testing and care can be given.
“We are investigating potential causes and working hard to build better awareness amongst health care professionals about how to test and manage patients with AFP.”
There have been more than 120 cases of AFP reported in the US in 2018 so far, with 62 confirmed across 22 states, according to the Centre for Disease Control.