The authorities said the virus has evolved into a "vaccine-derived" poliovirus type 2 (VDPV2) that has the potential to spread in communities and can cause serious illness, such as paralysis.
Dr. Vanessa Saliba, a UKHSA consultant epidemiologist, said the overall risk to the public is extremely low, but called on parents to have their children updated on polio vaccines as they investigate a possible outbreak of the disease.
The agency added that it is normal to find one to three "vaccine-like" polioviruses in routine checks of sewage samples because people who travel to the U.K., after having the live oral polio vaccine overseas, briefly shed traces of the poliovirus in their feces.
Experts are looking at the possibility that just one family may be affected, though it is unclear how many people need to be infected for polio to be detected in sewage samples.
The country generally has good uptake of the polio vaccine as 95 percent of five-year-olds were already vaccinated. However, vaccine coverage has decreased especially in parts of London over the past few years, with only 71 percent of children vaccinated in that age bracket.
National Health Service (NHS) Chief Nurse Jane Clegg stated that the NHS will begin contacting parents of children aged under five in London "who are not up to date with their polio vaccinations to invite them to get protected."
In 2014, the U.K. switched from using the oral polio vaccine to an inactivated polio vaccine administered by injection. The jabs are given in routine NHS childhood vaccinations at eight, 12 and 16 weeks as part of the 6-in-1 vaccine. Boosters are provided at the age of three and 14.
The World Health Organization (WHO) has declared the U.K. since 2003 after its last confirmed case of wild polio in 1984.
In 2021, the Global Polio Eradication Initiative, a public-private partnership led by national governments and six partners launched a five-year strategy that outlines new tactics to address barriers to ending all forms of polio. The partners in this effort are the WHO, Rotary International, the U.S. Centers for Disease Control and Prevention, United Nations Children's Fund, Bill & Melinda Gates Foundation and Gavi, the Vaccine Alliance. (Related: MEDICAL MADNESS: Bill Gates developing new vaccine that claims to prevent polio caused by polio vaccines.)
After Big Pharma clinical trials, the Gates-funded polio vaccine, one that will supposedly counteract polio-vaccine-caused polio, was approved last year for emergency use by the WHO.
In recent years, polio incidence has started to slow down because of the type of vaccine used, primarily in low- and middle-income countries. While Western countries inject an inactivated virus that poses no risk of spread and are now polio-free, other countries rely on an oral vaccine.
"Those who've been immunized with the live virus can shed it in their stool, which can then spread through sewage in places with poor sanitation. If the virus stays weak, it can expose the unvaccinated to polio and give them immunity. But if it mutates and regains virulence, someone who isn't vaccinated can become sick with vaccine-derived polio after contact with the contaminated wastewater," the NPR reported back in April.
"What we did is three independent modifications to make reactivation less likely," said Ananda Bandyopadhyay, deputy director for polio at the Gates Foundation.
Bandyopadhyay said the researchers tweaked the virus so that it has to accumulate more mutations to become virulent and will have a harder time amassing those mutations. He added that they've altered the polymerase, one of the key enzymes responsible for introducing mutations, reducing its ability to mix and match genes from different viruses.
Visit Infections.news for more stories about vaccine-derived poliovirus.
Watch the below video that talks about the recent uptick in vaccine-derived polio in Africa and parts of Asia.
This video is from the High Hopes channel on Brighteon.com.