Aug. 10, 2022 -- At the end of June, the United Kingdom Health Security Agency announced an urgent investigation after finding the polio virus in wastewater samples, suggesting a likelihood of some community transmission.

In a briefing this morning, the agency confirmed their suspicions and have announced they plan to vaccinate all children age 1-9 in London to strengthen protection against paralysis and boost immunity. From Feb. 8 to July 5, polio virus was detected 116 times in 19 sewage samples from London.

There have been no confirmed cases of polio, and the UKHSA says that the risk to the population is "low" as most people are protected by vaccination. The last case of polio in the UK was in 1984.

About 87% of Londoners are vaccinated against polio, including about 71% of young children. Both figures, however, are lower than the World Health Organization’s target of 95% coverage.

Vaccination to Use the Inactivated Polio Virus

The booster vaccination program will use the inactivated polio vaccine. It will start immediately, concentrating on areas where the virus was found and in those with lower vaccination rates.

While most adults are vaccinated against polio, some who receive the oral vaccine can still get polio infections in the gut that are asymptomatic but can be transmitted to others -- and this can be a danger to people who are not vaccinated.

Good hygiene can usually control the spread. “Whilst rare, these vaccine-derived polioviruses have lost their attenuating mutations and are just as likely as the wild-type strain to cause paralysis,” Nicholas Grassly, professor of vaccine epidemiology, at Imperial College London, said. “The National Health Service in London will contact parents when it's their child's turn to receive the booster vaccine. This booster dose will be in addition to the NHS childhood vaccination catch up campaign across London.

Vanessa Saliba, consultant epidemiologist at UKHSA said: "It is vital parents ensure their children are fully vaccinated for their age. “All children aged 1 to 9 years in London need to have a dose of polio vaccine now –whether it's an extra booster dose or just to catch up with their routine vaccinations. It will ensure a high level of protection from paralysis. This may also help stop the virus spreading further."

Chief nurse for the NHS in London, Jane Clegg, said: "We are already reaching out to parents and carers of children who aren’t up to date with their routine vaccinations, who can book a catch-up appointment with their GP surgery now