U.K. health authorities have said they are urgently investigating a rare polio virus discovery in sewage samples in London, potentially putting Britain’s polio-free status at risk for the first time in almost two decades.
A number of waste samples from the Beckton sewage treatment works in Newham, east London tested positive for vaccine-derived polio virus between February and May, the U.K. Health Security Agency said Wednesday.
The virus has since continued to evolve and is now classified as a “vaccine-derived” polio virus type 2, the UKHSA said, adding that it is looking to establish if any community transmission is occurringEach year, it is usual for one to three “vaccine-like” polio viruses to be detected in Britain’s sewage system.
Such detections have always been one-off findings, and have previously occurred when an individual vaccinated overseas with the live oral polio vaccine returned or traveled to the U.K. and briefly “shed” traces of the vaccine-like polio virus in their feces.
However, this marks the first time a cluster of genetically-linked samples has been identified repeatedly over several months.
R&I – FS