A national incident was declared in England after evidence of transmission of poliovirus was detected


Public health officials have declared a national incident and informed the World Health Organization of the situation after routine surveillance of wastewater in north and east London found evidence of community transmission of poliovirus. It potentially could change Britain’s polio-free status for the first time in almost two decades. Prof Nicholas Grassly, the head of the vaccine epidemiology research group at Imperial College London, however said: “Polio is a disease that persists in some of the poorest parts of the world and the UK quite frequently detects importation of the virus during routine testing of sewage.The outbreak is believed to have been triggered by a person returning to the UK after having the oral polio vaccine and spreading it locally.No cases of the disease or related paralysis have been reported, and the risk to the general public is considered low. Polio is a rare virus that can occasionally cause serious illness, such as paralysis, in people who are not fully vaccinated with three shots given before the age of one and another shot given at ages three and 14.“Most of the UK population will be protected from vaccination in childhood, but in some communities with low vaccine coverage, individuals may remain at risk,” Dr Vanessa Saliba, consultant epidemiologist at the UKHSA, said. Tests on UK sewage typically pick up a handful of unrelated polioviruses each year. These come from people who have been given the oral polio vaccine in another country and then travel to the UK. Poliovirus can spread through poor hand hygiene and contaminated food and water. In response to the detection of the virus, the NHS will contact parents of children who are not up to date with their polio vaccinations.


Generally, those who do become infected with polio display no symptoms, though some can develop a flu-like illness up to three weeks later. In between one in 100 and one in 1,000 infections, the virus attacks nerves in the spine and the base of the brain, which can lead to paralysis, most commonly in the legs.