The virus which causes polio has been detected in the UK for the first time in almost 40 years.

Traces of the virus was found in London’s Beckton sewage treatment works between February and May indicating that the infection may have spread between a small number of people although no cases have been confirmed.

The last case of polio in the UK was recorded in 1984.

Parents of children who have not been fully vaccinated against the illness have been advised by the UK Health Security Agency (UKHSA) to ensure the youngsters are jabbed as soon as possible.

The UK is now on the verge of losing its polio-free status issued by the World Health Organization for the first time since 2003.

Since 2004 inactivated polio vaccines (IPV) offering 100% protection against paralysis, which affects 1% of polio cases, have been rolled out across the UK.

Today’s new case is thought to be traced back to an individual who received the oral polio vaccine (OPV) in Pakistan, Afghanistan or Nigeria before travelling to the UK in 2022.

The OPV vaccine was replaced in the UK in 2004 as, in some instances, the milder treatment led to “vaccine-derived poliovirus”, also known as type 2 polio. 

Doctors, especially those in the London area, have been advised by the UKHSA to look out for polio symptoms.

According to the World Health Organization the discovery of a vaccine-derived poliovirus in the sewage  “suggests it is likely there has been some spread between closely linked individuals in north-east London and that they are now shedding the type 2 poliovirus strain in their faeces.

The virus has only been detected in sewage samples and no associated cases of paralysis have been reported but investigations will aim to establish if any community transmission is occurring”.

Dr Vanessa Saliba, consultant epidemiologist at UKHSA said: “Vaccine-derived poliovirus is rare and the risk to the public overall is extremely low.

“Vaccine-derived poliovirus has the potential to spread, particularly in communities where vaccine uptake is lower.

“On rare occasions it can cause paralysis in people who are not fully vaccinated so if you or your child are not up to date with your polio vaccinations it’s important you contact your GP to catch up or if unsure check your red book.

“Most of the UK population will be protected from vaccination in childhood, but in some communities with low vaccine coverage, individuals may remain at risk.

“We are urgently investigating to better understand the extent of this transmission and the NHS has been asked to swiftly report any suspected cases to the UKHSA, though no cases have been reported or confirmed so far.”

Polio can strike at any age, but it mainly affects children under five.