Health chiefs have warned that polio could be infecting the UK, for the first time since nearly 40 years. They declared it a “national incident” today.
Officials found evidence of the virus’ vaccine-derived variant in samples of sewage in London. They believe that it could be spreading within the area.
After the school closures and pandemic, parents are being asked to make sure their children receive their polio shots.
British children should have the first of three shots against polio as babies. But London has a lower rate than the rest of Britain.
One in 100 cases of permanent paralysis can be caused by polio, which is spread through coughs, sneezes and contact with objects contaminated in faeces. The risk is higher for children.
The virus was detected several times between February and May and has continued to mutate, according to the UK Health Security Agency (UKHSA).
Someone who had been vaccinated in the UK with live polio vaccine (which contains a weaker virus version) may have traveled abroad to get rid of some of their stool.
However, health officials claim that the overall risk is low for the general public. Therefore, urgent investigations are underway to identify anyone infected.
Although polio was not reported in the UK until 1984, there have been many cases imported from elsewhere. In 2003, Britain was declared free from polio.
The outbreak comes just as London faces an outbreak of monkeypox. This is another viral disease of rare importance that used to be restricted to western and central Africa.
As part of the six in one vaccine, the polio vaccine can be given to children at ages eight, twelve and sixteen weeks. The vaccine can also be administered at three-year-old as part a booster program. At age 14, the final course of polio vaccine is administered. At age 14, the final course is given. The World Health Organization sets the benchmark for a school jabs program that’s successful at 95% uptake. England has failed to meet this threshold by any accounts.
After the outbreak, parents are being asked to make sure their children have current polio vaccines. The NHS offers a four-in-1 pre-school vaccination to a young girl.
British children getting their oral vaccine for polio in 1965 — which used a live version of the virus — 12 years after the first vaccine was invented
Patients were treated with an iron lung when polio affected the muscles that are used for breathing. Pictured is a patient with iron lung. She was at Fanzakerley Hospital, Liverpool.
The UKHSA said it found ‘several closely related’ polioviruses in samples collected from the London Beckton Sewage Treatment Works in Newham.
Although no confirmed cases yet, the UKHSA stated that it was likely that there had been spread among closely-related individuals in North London and East London.
It is normal for traces of the virus to be occasionally detected as part of routine testing of sewage, but the findings are normally a one-off.
These normally come from people who were vaccinated with the live oral vaccine overseas and then travelled to the UK. People given the oral vaccine can shed the weakened live virus used in the vaccine in their faeces for several weeks.
Most countries have switched to polio jabs that use inactivated pieces of virus but some developing nations still rely on the live vaccine.
The London samples have caused concern because they were from different people and contained two mutations that suggest the virus is evolving as it spreads between people.
It is unclear how far the virus has spread but it is hoped the outbreak will be contained to a single household or family.
Polio used to paralyse millions of children around the world every year in the 1940s and 1950s and consign thousands to ‘iron lungs’ — large and expensive machines that helped them breathe.
Most people show no signs of infection at all but about one in 20 people have minor symptoms such as fever, muscle weakness, headache, nausea and vomiting.
Around one in 50 patients develop severe muscle pain and stiffness in the neck and back.
Less than one per cent of polio cases result in paralysis and one in 10 of those result in death.
Dr Vanessa Saliba, a consultant epidemiologist at the UKHSA, said: ‘Vaccine-derived poliovirus is rare and the risk to the public overall is extremely low.
‘Vaccine-derived poliovirus has the potential to spread, particularly in communities where vaccine uptake is lower.
‘On rare occasions it can cause paralysis in people who are not fully vaccinated so if you or your child are not up to date with your polio vaccinations it’s important you contact your GP to catch up or if unsure check your red book.
‘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.’
The polio vaccine is offered as part of the NHS routine childhood vaccination programme.
It is given at age eight, 12 and 16 weeks as part of the six-in-one vaccine and then again at three years as part of a pre-school booster. The final course is given at age 14.
Uptake has fallen slightly nationally during the Covid pandemic but remains above 90 per cent nationally. Rates are lower in London and in poor and ethnic minority communities.
Just 86.7 per cent of one-year-olds in London have had their first dose dose of polio vaccine compared to the UK average of 92.6 per cent.
There are concerns vaccine hesitancy has risen during the Covid crisis due to misinformation spread about jabs for that virus and school closures.
Polio is a highly infectious disease that spreads through coughs and sneezes, bodily fluids or in food, water, clothing or other objects contaminated with faeces.
The virus lives in the throat and intestines for up to six weeks, with patients most infectious from seven to 10 days before and after the onset of symptoms.
But it can spread to the spinal cord causing muscle weakness and paralysis.
The virus is more common in infants and young children and occurs under conditions of poor hygiene.
There are three strains of ‘wild’ polio, which has been largely eradicated throughout Europe, the Americas, Southeast Asia and the Western Pacific.
Types 2 and 3 were eliminated thanks to a global mass vaccine campaign, with the last cases detected in 1999 and 2012 respectively.
The remaining, type 1, wild polio remains endemic in only two countries, Afghanistan and Pakistan.
Cases have fallen from 350,000 in 1988 to just 33 reported cases in 2018, according to the World Health Organization.
There are still occasionally sporadic cases of vaccine-derived polioviruses, however.
Polio used to paralyse millions of children around the world every year in the 1940s and 1950s but has been eliminated in virtually every country thanks to vaccines
The remaining, type 1, wild polio remains endemic in only two countries, Afghanistan and Pakistan but parts of Africa still suffer flare-ups
These are strains that were initially used in live vaccines but spilled out into the community and evolved to behave more like the wild version.
Vaccine-derived poliovirus type 2 (VDPV2), the one that has been detected in London, is the most common type. There were nearly 1,000 cases of VDPV2 globally in 2020.
Since 2019 every country in the world has been using vaccines that contain inactivated versions of the virus that cannot cause infection or illness.
But the UKHSA said countries where the virus is still endemic continue to use the live oral polio vaccine (OPV) in response to flare-ups.
That vaccine brought the wild poliovirus to the brink of eradication and has many benefits.
But in areas with low vaccination rates, the virus present in the jab can spread and acquire rapid mutations that make it as infectious and virulent as the wild type.
Professor David Heymann, an infectious disease expert at the London School of Hygiene & Tropical Medicine, said: ‘The fact that it has been found in sewage in the UK attests to the strength of the surveillance programmes of UKHSA.
‘Its presence in the reminds us that polio eradication has not yet been completed in the world.
‘The high vaccination coverage using inactivated polio vaccine in the UK will limit the spread of vaccine derived polio and protect those who have been vaccinated against polio paralysis.’
The UK’s drugs watchdog and the World Health Organization are working on a vaccine specifically for vaccine-derived polio strains.
It is already being used in parts of Africa, including Nigeria, where these types of strains are endemic.
Dr David Elliman, consultant paediatrician at Great Ormond Street Hospital, said the finding strengthened the importance of vaccinating against eradicated diseases.
‘Parents sometimes ask why, when diseases are uncommon in UK, or in the case of polio has been eliminated, do we continue to vaccinate against them.
‘The answer is that, although we are an island, we are not isolated from the rest of the world, which means diseases could be brought in from abroad.
‘The finding of vaccine derived polio virus in sewage proves the point. Although the uptake of polio vaccines is high in UK, there are children who are unimmunised and therefore at risk of developing polio if in contact with this virus.
‘The risk is small, but it is easily preventable by the vaccine, which in the UK is killed and so cannot cause the disease.
‘There is no upper age limit for the vaccine. Anyone who is not fully vaccinated against polio should seek advice from their health visitor or general practice.’
Can I take the polio vaccine if I missed out as a child? What are the virus’ symptoms? How many people are infected in the UK? EVERYTHING you need to know amid fears paralysis-causing virus is spreading
By EMILY CRAIG HEALTH REPORTER FOR MAILONLINE
Wasn’t polio eradicated?
There are three versions of wild polio – type one, two and three.
Type two was eradicated in 1999 and no cases of type three have been detected since November 2012, when it was spotted in Nigeria.
Both of these strains have been certified as globally eradicated.
But type one still circulates in two countries – Pakistan and Afghanistan.
These versions of polio have been almost to extinction because of the polio vaccine.
However, the global rollout of vaccines has resulted in new strains called vaccine-derived Polioviruses.
These strains are those that originated in live vaccines and then spread to other communities. They have evolved to be more similar to wild versions.
How many people are infected?
Health chiefs haven’t yet detected an actual case.
Instead, they have only spotted the virus in sewage samples.
But they said several closely-related polio viruses were found in sewage samples taken in North and East London between February and May.
This suggests there has ‘likely’ been spread between linked individuals who are now shedding the strain in their faeces.
The UK Health Security Agency is investigating if any community transmission is occurring.
It is hoped that the cases will be confined to a single household, or extended family.
How does it spread?
Like Covid it can spreads when someone inhales particles expelled by an infected person who coughs or sneezes.
But it can also be spread by coming into contact with food, water, or objects that have been contaminated with faeces.
Places with a high population, poor sanitation and high rates of diarrhoea-type illnesses are particularly at risk of seeing polio spread.
Unvaccinated people are at a high risk of catching the infection.
There is some concern that the virus appears to be spreading in London because it has poorer polio vaccine uptake than the rest of the country.
What does a national incident mean?
UKHSA guidelines set out that when a vaccine-derived polio virus is spotted in Britain.
This instructs health chiefs to set up a national response to manage and coordinate how it responds.
It includes joining up local public health teams.
While the polio samples have only been spotted in London, health chiefs say it is vital to ensure other parts of the country are aware and taking necessary action to protect people in their area.
How is polio treated?
There is no cure for polio, although vaccines can prevent it.
Treatment can only alleviate its symptoms and lower the risk of long-term problem.
Mild cases – which are the majority – often pass with painkillers and rest.
But more serious cases may require a hospital stay to be hooked up to machines to help their breathing and be helped with regular stretches and exercises to prevent long-term problems with muscles and joints.
In the 1920s, the iron lung – a respirator that resembled a ‘coffin on legs’ – was used to treat polio.
It was first used that decade to save a child infected with the virus who needed help breathing.
Paul Alexander, 76, from Texas, is still in the machine today, 70 years later, after contracting polio at the age of six in 1952.
I missed out on a vaccine as a child, can I still get it?
Health chiefs have encouraged everyone who is unvaccinated against polio to contact their GP to catch up.
However, they warned vaccination efforts in London will focus initially on reaching out to parents of under-fives that have not had or missed their jabs, amid fears it is spreading in the capital.
The NHS currently offers the polio jab as part of a child’s routine vaccination schedule. The polio vaccine is included in the six-in-one vaccination, which is given to children when they are eight, 12 and 16 weeks old.
Protection against polio is boosted in top-up jabs when youngers are three-years-and-four-months old and when they are 14.
Most Londoners are fully jabbed against polio. But uptake is not 100 per cent.
Can it kill?
Polio can kill in rare cases. But it is more famous for causing paralysis, which can lead to permanent disability and death.
Up to a tenth of people who are paralysed by the virus die, as the virus affects the muscles that help them breathe.
What are polio’s symptoms?
Three-quarters of people infected with polio do not have any visible symptoms.
Around one-quarter will have flu-like symptoms, such as a sore throat, fever, tiredness, nausea, a headache and stomach pain. These symptoms usually last up to 10 days then go away on their own.
But up to one in 200 will develop more serious symptoms that can affect the brain and spinal cord. This includes paraesthesia – pins and needles in the leg – and paralysis, which is when a person can’t move parts of the body.
This is not usually permanent and movement will slowly come back over the next few weeks or months.
However, even youngsters who appear to fully recover from polio can develop muscle pain, weakness or paralysis as an adult – 15 to 40 years after they were infected.
Do vaccines cause polio?
Although extremely rare, cases of vaccine-derived polio have been reported.
They do not make the vaccinated person ill but rather cause them to shed tiny pieces of the virus, which can then infect other, unvaccinated people.
This is only the case with the oral polio vaccine, which uses a live and weakened version of the virus to stimulate an immune response.
That jab has brought the virus to the brink of extinction and works by providing immunity in the gut, which is where polio replicates.
But it carries the small risk of infecting others, mostly through contact with faeces because it lives in the gut for several weeks after vaccination.
If lots of people are not jabbed and encounter the virus in this way, the virus can spread multiple times and rapidly mutate until it starts acting like the wild type of the virus, which can cause paralysis.
How did polio end up in the UK?
The polio spotted in Britain was detected in sewage, which is monitored by health chiefs, rather than in a person.
This suggests the virus has been imported from a country where the live polio vaccine is still being used.
Professor Paul Hunter, an infectious disease expert at the University of East Anglia, said: ‘Such vaccine derived transmission events are well described and most ultimately fizzle out without causing any harm but that depends on vaccination coverage being improved.’
Could this trigger an outbreak?
Uptake of the polio vaccine is around 90 per cent across the UK so it is unlikely to cause a massive outbreak.
But it has dipped further over the last year due to the knock-on effects of the pandemic.
Due to misinformation about vaccines and closures of schools, there are fears that vaccine hesitancy may have increased during the Covid crisis.
Experts say the best way to prevent the virus from spreading is for Britons to ensure their vaccinations are up to date, especially for children.
Kathleen O’Reilly, an associate professor of statistics in infectious diseases and expert in the eradication of polio, stated that every country is at risk until all cases have been stopped worldwide.
The ‘highlights’ of polio eradication and global support are needed, she said.
How many cases of polio were there in Britain last year?
In 1984, the UK saw its last case of polio. The UK became polio-free in 2003.
There have been numerous imported cases over the years, and these are frequently detected by sewage surveillance.
However, these have always been one-off findings that were not detected again and occurred when a person vaccinated overseas with the live oral polio vaccine travelled to the UK and ‘shed’ traces of the virus in their faeces.
UK officials discovered several viruses that were closely related in samples of sewage taken from February to May. These results suggest that the virus has spread to North London and East London from where it was first discovered.
Where did polio originate?
The late 1800s were the first time that polio epidemics (when the virus spreads in a community) began to occur.
Scientists believe it’s an old disease, which first affected Egyptians in 1570 BC. Based on images of weak limbs and paralysis from this time, it is possible to conclude that the disease originated in Egypt.
In 1789, a London doctor published the first clear description of Poliomyelitis in Infants.