(Web Desk) - Four instances of poliovirus, commonly known as polio, have been identified in sewage samples from Leeds (two samples), London, and West Sussex.
The samples tested positive for vaccine-derived poliovirus type 2 (VDPV2).
According to Travel Health Pro, this strain is linked to the weakened live poliovirus in the oral polio vaccine (OPV).
Polio can be transmitted from person to person. It usually spreads through contact with the faeces of an infected person.
For example, from not washing your hands properly and putting them in your mouth or from contaminated food or water.
It can also spread through coughing or sneezing, which is less common.
The Centres for Disease Control and Prevention (CDC) said:
“If allowed to circulate in [under-immunised] or unimmunised populations for long enough, or replicate in an immunodeficient individual, the weakened virus can revert to a form that causes illness and paralysis.”
In rare instances, polio can lead to more serious symptoms that affect the brain and nerves. Severe symptoms include muscle weakness (paralysis), typically in the legs.
The NHS noted that “[t]his can occur over hours or days”, going on to assert:
“If the paralysis affects the muscles used for breathing, it can be life-threatening.
“Most people will recover, and movement will slowly come back over the next few weeks. Some individuals may be left with permanent disability.”
Most people infected with polio do not experience symptoms. Some may experience mild flu-like symptoms.
The World Health Organisation (WHO) declared Europe polio-free in 2002 due to the vaccine.
Nevertheless, Finland reported a case of VDPV2 in wastewater samples in December 2024.
On December 13, 2024, regarding the strains detected in the UK, Travel Health Pro maintained:
“To date, there is no evidence of community transmission, and the risk to the public is low.”
This is not the first time polio has been found in UK wastewater. It was also found in 2022 and at the time, the NHS said:
“Although some poliovirus has been found in sewage from London recently, the risk of getting it remains extremely low.”
The polio vaccine is offered in the UK as part of the NHS routine childhood vaccination schedule.