Polio warning for north-east LondonLondoners being urged to check they are vaccinated against polio
Poliovirus has been detected in London sewage, leading the government to warn residents – particularly in the north-east of the capital – to ensure they and especially any young children are fully vaccinated.
Polio is a stomach bug that can, in a very small number of cases, spread to the nervous system and cause muscle weakness, paralysis or even death.
Following a successful vaccination programme, the UK was officially declared ‘polio free’ in 2003, with the last ‘wild’ case confirmed in 1984.
However, between February and May this year, samples collected at Beckton Sewage Treatment Works in Newham contained “several closely related” strains of the virus, suggesting “there has been some spread between closely linked individuals in north-east London”.
So far, there have been no reported cases of polio-related paralysis and “the risk to the public overall is extremely low”, according to the UK Health Security Agency (UKHSA).
Dr Vanessa Saliba, consultant epidemiologist at UKHSA, said: “Poliovirus is rare… [but] 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.”
The virus strains found are believed to have mutated from a weakened but living form of the poliovirus used to vaccinate people in some foreign countries, which has not been used in the UK since 2004.
Those vaccinated with the live form of the virus can shed it in their faeces for several weeks after being vaccinated and it is normal for one to three ‘vaccine-like’ strains to be detected in UK sewage each year from people vaccinated abroad.
However, these weaker “vaccine viruses” can spread in under-vaccinated communities and, in the process, mutate into a stronger “vaccine-derived poliovirus”, which behaves more like the original strain.
Covid-19 vaccines do not use a live form of the virus, meaning a similar phenomenon will not happen.
Jane Clegg, chief nurse for the London NHS, said: “The majority of Londoners are fully protected against polio and won’t need to take any further action, but the NHS will begin reaching out to parents of children aged under five in London who are not up-to-date with their Polio vaccinations to invite them to get protected.
“Meanwhile, parents can also check their child’s vaccination status in their red book and people should contact their GP practice to book a vaccination should they or their child not be fully up-to-date.”
The poliovirus spreads easily from person to person through poor hand hygiene or, less commonly, through coughing and sneezing.
Most people will have no symptoms and not realise they are infected, a small number of people will experience a flu-like illness up to 21 days after infection.
In a small number of cases, between 1 in 100 to 1 in 1000 infections, the polio virus attacks the nerves in the spine and base of the brain and can become more serious.
If you or your child experience unusual symptoms that could be the beginning of paralysis, you should always seek medical advice immediately.
You should also get vaccinated even if you’ve had polio before as the vaccine protects against three different types of poliovirus.