Since the virus was detected in sewage samples collected from the London Beckton Sewage Treatment Works, which covers parts of North and East London, the UK Health Security Agency (UKHSA) has announced it will be expanding the surveillance programme to areas outside of the capital.
The government body will work with the Medicines and Healthcare product Regulatory Agency (MHRA) to take further samples on a precautionary basis, at areas chosen on a basis of risk. Sampling will be rolled out at sewage treatment works covering parts of Birmingham, Blackburn with Darwen, Bradford, Brighton and Hove, City of Bristol, Bury, Castle Point, Leeds, Leicester, Liverpool, Luton, Manchester, North Tyneside, Newcastle upon Tyne, Gateshead, Nottingham, Preston, Salford, Sheffield and Watford.
The areas are chosen based on their demographics, including areas adjacent to London locations where polio has been detected, and areas with low polio vaccination coverage.
To date only London and Glasgow have been subject to testing with no polio detected in the latter.
Areas with “population groups living in the area with links to countries overseas where wild poliovirus is still found or where live oral polio vaccine is still used” will also be surveilled, according to UKHSA. The only two countries where wild poliovirus is still considered to be found are Afghanistan and Pakistan according to the World Health Organisation (WHO).
There is no cure for polio, but it can be prevented by vaccination, global efforts such as the Global Polio Eradication Initiative which was set up in 1988 hoping to completely eradicate the disease worldwide. Polio mainly impacts children under the age of five, with one in 200 cases resulting in paralysis. At the time, 350,000 cases of polio were reported worldwide but the figure fell 99% by 2000.
The national risk of paralytic polio, where the virus attacks the brain and spinal cord causing paralysis, is considered low in the UK as most people are protected by the polio vaccine. On August 10 the Joint Committee on Vaccination and Immunisation (JCVI) advised that a targeted inactivated polio vaccine (IPV) booster dose should be offered to all children between the ages of 1 and 9 in all London boroughs.
Dr Vanessa Saliba, Consultant Epidemiologist at UKHSA, said: “No cases of polio have been reported and for the majority of the population, who are fully vaccinated, the risk is low. We are now expanding the sewage sampling nationally to areas that are at highest risk of new poliovirus importations and areas most likely to see spread of poliovirus from London.
“We are in touch with public health colleagues in these areas and will work closely with local areas as the need arises.
“In the meantime it is vital parents across the country check their children are fully vaccinated for their age.”
The sewage sampling strategy will continue to be reviewed and adapted as new evidence emerges, according to UKHSA.