British health authorities have said they are “urgently” investigating a rare finding of poliovirus in sewer samples in London.
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The British health authorities have said they are quickly investigating a rare finding of poliovirus in sewer samples in London, which potentially puts Britain’s polio-free status at risk for the first time in almost two decades.
A series of waste samples from Beckton’s sewage treatment plant in Newham, east London, tested positive for vaccine-derived poliovirus between February and May, the British health safety agency said on Wednesday.
The virus has since continued to develop and is now classified as a “vaccine-derived” poliovirus type 2, said UKHSA, adding that it is looking to find out if there is any transmission of society.
The agency has declared a national incident and informed the World Health Organization of the situation.
“We are investigating rapidly to better understand the extent of this transmission, and the NHS has been asked to promptly report all suspected cases to the UKHSA, although no cases have been reported or confirmed so far,” Dr. Vanessa Saliba, consultant epidemiologist at the UKHSA, said Wednesday.
Polio is a rare virus that can sometimes cause serious illness, such as paralysis, in people who have not been vaccinated. The disease was previously common in Britain in the 1950s, but the country was declared polio-free in 2003.
UKHSA said the risk to the general public is extremely low, but urged parents to ensure that their children are fully vaccinated against the disease. It is common practice in the UK for children to receive an inactivated polio vaccine as part of their routine vaccination program; with three shots given before the age of one and another shot given at the ages of three and 14 years.
“Most of the UK population will be protected from childhood vaccination, but in some communities with low vaccine coverage, individuals may still be at risk,” Saliba said.
Every year, it is common for one to three “vaccine-like” polioviruses to be detected in the UK’s sewer system.
Such detections have always been one-time findings, and have previously occurred when an individual vaccinated abroad with the live oral polio vaccine returned or traveled to the UK and briefly “threw” traces of the vaccine-like polio virus in the feces.
However, this is the first time a cluster of genetically linked samples has been identified repeatedly over several months.
Researchers say this suggests that there has been a society scattered among closely related individuals in north and east London.
So far, the virus has only been detected in sewage samples, and no associated cases of paralysis have been reported, according to UKHSA.
While polio vaccination is common in the UK, vaccination rates vary across the country, with communities with lower admissions at greater risk.
Vaccine coverage for childhood vaccines, in particular, has declined nationally and especially in parts of London in recent years.
The UK’s national health service said parents should contact the doctor’s office to check that their child’s vaccines are up to date.
“The majority of Londoners are completely protected from polio and need do nothing more, but the NHS will start contacting parents of children under the age of 5 in London who are not up to date with their polio vaccinations to invite them to be protected,” said Jane Clegg , Chief Nurse for the NHS in London.
“In the meantime, parents can also check the child’s vaccination status in their red book, and people should contact their GP to order a vaccination, if they or their child is not completely up to date,” she added.
In 2004, the United Kingdom switched from using an oral polio vaccine to an inactivated polio vaccine, which is administered by injection and prevents infection.
Usually, those infected with polio show no symptoms, although some may develop a flu-like illness up to three weeks later. In rarer cases, the virus can attack nerves in the spine and base of the brain, potentially leading to paralysis. Sometimes it can attack muscles used to breathe, which can be fatal.
Medical professionals said that early detection of the virus would be important to monitor the spread and prevent more serious cases.
“In populations with low vaccine uptake, it is possible that the live polio vaccine can spread from one person to another. If this is maintained, this vaccine-derived virus may over time (one or two years) mutate to become completely virulent again and may begin to cause paralysis in people who have not been vaccinated, “said Paul Hunter, a professor of medicine at the University of East Anglia.