London, August 11 / BNA / Britain is launching a booster polio vaccination campaign for children in London under the age of 10, after confirming the spread of the virus in the capital for the first time since the eighties.
The UK’s Health Security Agency identified 116 polioviruses from 19 wastewater samples this year in London. Reuters reported that it raised the alert for the first time about finding the virus in sewage samples in June.
The agency said on Wednesday that levels of the polio virus that have since been discovered and the genetic diversity suggested transmission was occurring in a number of London boroughs.
No cases have been identified yet, but in an effort to beat a potential outbreak, doctors will now invite children ages 1 to 9 to get their booster vaccinations, along with a broader catch-up campaign that has already been announced. Immunization rates vary across London, but are on average below the 95% coverage rate that the World Health Organization suggests is necessary to control polio.
Polio, which is spread mainly by fecal contamination, is used to kill and paralyze thousands of children annually worldwide. There is no cure, but vaccination has brought the world closer to ending the wild, or naturally occurring, form of the disease. It paralyzes less than 1% of affected children.
The virus in London wastewater is essentially the vaccine-like virus, which appears when children are vaccinated with a certain type of live vaccine – now only used outside – that sheds the virus in their faeces. This harmless virus can be passed between unvaccinated children, and while doing so, it can mutate again into a more dangerous version of the virus, causing illness.
Last month, the United States detected a case of polio outside New York in an unvaccinated individual, the first in a decade. The UK Health Services Authority (UKHSA) said the condition was genetically linked to the virus seen in London.
Britain is also working to expand polio surveillance to other sites outside London to see if the virus has spread further. The risk to the general population is assessed as low because most people are vaccinated even if rates are below optimal levels to prevent spread.
MI