Poliovirus Detected in Yorkshire and the Humber Sewage, Second UK Detection in 2025

Poliovirus Detected in Yorkshire and the Humber Wastewater

Vaccine-derived poliovirus type 2 (VDPV2) has been detected in an environmental sewage sample collected in Yorkshire and the Humber, northern England. The sample, gathered on September 16, 2025, marks the second VDPV2-positive environmental sample reported in the United Kingdom this year. The detection was reported by the Global Polio Eradication Initiative (GPEI).

Understanding Vaccine-Derived Poliovirus Type 2

VDPV2 is a strain of poliovirus related to the weakened live poliovirus contained in the oral polio vaccine (OPV). While the UK switched from OPV to the Inactivated Polio Vaccine (IPV) in 2004, the weakened virus can, if allowed to circulate in under- or unimmunized populations for long enough, revert to a form that can cause illness and paralysis. Most individuals infected with poliovirus do not experience symptoms, but some may have minor ailments like fever or headache. In rare instances, it can lead to permanent loss of muscle function.

Recent Detections and Surveillance Efforts

This detection in Yorkshire and the Humber follows an earlier VDPV2 finding in 2025 from a sewage sample collected at Shoreham Sewage Treatment Works (STW). The UK Health Security Agency (UKHSA) maintains a routine poliovirus surveillance program, testing sewage samples across 26 sites in the UK monthly. In late 2024, VDPV2 was also detected in samples from various locations, including East Worthing, Leeds Knostrop, and London Beckton. These UK detections are part of a broader pattern, with VDPV2 also identified in wastewater samples in several other European countries between September and December 2024.

Public Health Response and Vaccination Importance

While the risk to the public in the UK is generally considered low, and there has been no evidence of community transmission associated with the recent 2025 detections, public health authorities emphasize the critical importance of vaccination. The U.S. Centers for Disease Control and Prevention (CDC) has included the UK in a Level 2 travel alert, recommending that adults who have completed their routine polio vaccine series consider a single, lifetime booster dose before traveling to listed destinations. Previous sustained detections in London in 2022 prompted an enhanced incident response and a recommendation for booster doses for children aged 1 to 9 years in the capital. The poliovirus isolates found in the UK are often genetically linked to VDPV2 strains circulating in several African countries, underscoring the global nature of polio eradication efforts.