LONDON: Four instances of poliovirus have been identified in wastewater samples across the United Kingdom, raising concerns among health authorities.
The samples, which tested positive for vaccine-derived poliovirus type 2 (VDPV2), were detected in Leeds (two samples), London, and West Sussex, according to Travel Health Pro.
VDPV2 is linked to the weakened live poliovirus used in the oral polio vaccine (OPV). While Europe was declared polio-free by the World Health Organization (WHO) in 2002, infrequent detections in wastewater have occurred, most recently in Finland in December 2024.
Transmission and Symptoms
Poliovirus spreads primarily through contact with the faeces of an infected person, often due to improper handwashing or consumption of contaminated food or water. Though less common, it can also spread through coughing or sneezing.
The Centres for Disease Control and Prevention (CDC) warned that if the weakened virus in OPV circulates in under-immunised or unimmunised populations for extended periods, it can mutate into a form capable of causing illness and paralysis.
Most individuals infected with poliovirus experience no symptoms, while some may develop mild flu-like symptoms.
In rare cases, the virus can cause severe complications, including paralysis, typically in the legs. The NHS stated that paralysis can develop within hours or days and, if it affects breathing muscles, may be life-threatening.
“Most people will recover, and movement will slowly come back over the next few weeks. However, some may be left with permanent disability,” the NHS noted.
Current Risk Assessment
Health authorities have assured the public that the risk remains low. Travel Health Pro reported on December 13, 2024, that there is “no evidence of community transmission” linked to the detected strains.
The NHS reiterated that the UK’s routine childhood vaccination program includes polio immunisation, significantly reducing the likelihood of widespread outbreaks.
This is not the first time poliovirus has been detected in UK wastewater. Similar findings occurred in London in 2022, prompting reassurances from the NHS that the risk of infection was “extremely low.”
