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 UK Health Security Agency (UKHSA) said Wednesday.
The virus was detected only in sewage samples, and no paralysis-related case has been so far reported, UKHSA stated, while reporting it has launched an investigation to determine if there is any type of transmission at the community level.
UKHSA also explained that one to three polio virus samples are usually found in all UK sewage per year, but the detection of two in the same treatment plant suggests there could be some level of transmission among individuals close to each other.
In the past, detections cropped up as a person returning to UK after receiving a live oral polio vaccine abroad, shedding the virus in their feces.
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 occurring.
The agency has declared a national incident and informed the World Health Organization of the situation.