The United States is among more than 100 countries that do not meet recommended vaccine coverage thresholds to control a potential outbreak of polio, leaving the US vulnerable to outbreaks of the devastating disease.
According to data from the Centers for Disease Control and Prevention (CDC), 92.6 percent of American children are vaccinated against polio by their second birthday, which is less than World Health Organization (WHO) limit of 95%.
The virus – which can cause paralysis in some patients – has been stopped in every country in the world except Pakistan And Afghanistan, The WHO has warned that as long as it is circulating in these countries, it remains a worldwide threat.
That danger was felt this week when Britain was put on high alert after remnants of the infection were found in the country’s sewage – a sign of at least one active infection.
While the uptake of the polio vaccine is strong in many countries – with over 90% coverage – many still fall short of the 95% mark set by the WHO to control potential infections. The US has a vaccine coverage of only 92%
The WHO collects data on the rate of one-year-olds suffering from polio.
WHO says countries with weakened polio vaccine are ‘particularly vulnerable’.
Like the US, the UK does not meet vaccination standards, with only 93 per cent vaccination coverage.
Only 46 countries that provided data to the WHO have met their recommended 95 percent target, including Australia, China and Japan.
But the uptake is less than half what it should be in some countries.
Only 41 percent of one-year-olds in Papua New Guinea are vaccinated against polio, with rates only slightly better in the African countries of the Central African Republic (46 percent), Somalia (47 percent) and Guinea (50 percent).
Polio can be a difficult disease to track, as most cases will not display the devastating symptoms that have become synonymous with it.
Many infections are either mild or asymptomatic. However, about one percent can result in paralysis and even death.
Children are believed to be most at risk from this disease, although it can also affect adults.
The United States has been free of polio for nearly three decades. The last case found on American soil was in 1993, when a person came into the country carrying the virus.
No cases have been reported in the US since 1979, 44 years since the infection occurred in the US.
Cases of polio are rare outside Pakistan and Afghanistan, where the virus is endemic. Global case rates have declined in recent decades after a vaccine was developed in 1955.
This is a notable change from the past decades where the virus ran rampant. The CDC reports that at one time, it disabled 35,000 Americans each year.
Notable cases include former US President Franklin Delano Roosevelt, whose polio infection left him paralyzed by garbage.
Kentucky Sen. Mitch McConnell, the Republican’s current minority leader, also suffered from polio at a young age, leaving his leg paralyzed. Since then he has fully recovered.
In 1955, the first polio vaccine was introduced in the US, heralding the end of the virus’s devastating regime.
Health officials recommend all children receive four doses of the vaccine: the first at two months of age, then at four months, six to 18 months of age, and then a final shot between four and six years of age.
Pictured: A woman is treated for polio in Liverpool, England
Image: Children get a sugar cube after receiving the oral polio vaccine in 1965
Cases of polio sometimes occur in countries where the virus is not commonly found.
Last year, Israeli authorities detected a case of the virus in a three-year-old girl who had not been vaccinated. This was the first case of the virus in the country after 1988.
Viruses are also occasionally detected in wastewater tracking in some developed countries. High vaccination coverage combined with the generally-benign nature of the virus increases the spread, although it does not spread.
It is usually spread through contact with infected food or water, usually through fecal contamination.
If a person consumes water contaminated with the feces of an infected person, he or she can also become infected.
Modern Water Sanitation TechniquesIt has been introduced to help significantly reduce the spread of the virus, especially in developed countries.
This is usually tested through a sample of blood or stool. There is no cure for the disease, but there are treatments available that can limit the long-term effects of symptoms on patient survival.
The ‘iron lung’, a mechanical respirator that helps a person breathe after a muscle is paralyzed, became an iconic symbol of the mid-century polio outbreak – as it helped avoid the devastating situation in some severe cases. Was the last gasp to do.
How long does the polio vaccine last? What are the symptoms of virus? How many people are infected in the UK? Everything you need to know amid fears about the spread of the paralyzing virus
Was polio not eradicated?
There are three forms of wild polio – type one, two and three.
Type two was eliminated in 1999 and no cases of type three have been detected since November 2012, when it was seen in Nigeria.
Both of these strains are globally certified as eradicated.
But Type One still airs in two countries – Pakistan and Afghanistan.
These versions of polio have been driven to near extinction due to vaccines.
But the global rollout has given rise to new types of strains known as vaccine-derived polioviruses.
These are strains that were initially used in live vaccines but have spread to the community and evolved to behave like the wild version.
How many people are infected?
Health chiefs have yet to detect an actual case.
Instead, they have only seen the virus in sewage samples.
But he said several related polioviruses were found in sewage samples taken in north and east London between February and May.
This suggests that there is a ‘likely’ spread among the connected individuals who are now reducing the strain in their stool.
The UK’s Health Protection Agency is investigating whether there is any community transmission.
It is expected that cases will be confined to nuclear family or extended family.
How does it spread?
It is spread between people through contact with food, water or objects contaminated with the feces of an infected person.
Places with high populations, poor sanitation and high rates of diseases such as diarrhoea, are especially prone to polio outbreaks.
Uninfected people are at higher risk of catching the infection.
There is some concern that the virus is spreading in London, where polio vaccines are worse than in the rest of the country.
How is polio diagnosed?
Doctors can diagnose polio based on their symptoms.
If a person is in the first week of an illness, a swab of their throat is taken, or a stool or blood sample may be taken for up to four weeks after symptoms begin.
The sample is then sent to a laboratory, with tests confirming whether the virus is present.
What is meant by national event?
UKHSA guidelines set out when a vaccine-derived poliovirus is seen in the UK.
It instructs health chiefs to establish a national response to manage and coordinate how to respond.
This includes joining local public health teams.
While samples of polio have only been seen in London, health chiefs say it is important to ensure that other parts of the country are aware and take necessary action to protect people in their region.
Image: A young girl in the UK received a shot of the polio vaccine
How is polio treated?
There is no cure for polio, although vaccines can prevent it.
Treatment can only ease its symptoms and reduce the risk of a long-term problem.
Mild cases — which are the majority — often pass with pain relievers and rest.
But more severe cases may require a hospital stay to help with their breathing and regular stretching and exercise to prevent long-term problems with muscles and joints.
In the 1920s, iron lunges – a respirator resembling a ‘coffin on the feet’ – were used to treat polio.
It was first used in that decade to rescue a child infected with the virus who needed help breathing.
76-year-old Paul Alexander from Texas is still in the machine 70 years later after contracting polio at the age of six in 1952.
I was not vaccinated as a child, can I still get it?
Health chiefs encourage all people who are not vaccinated against polio to contact their GP.
However, he warned that vaccination efforts in London would initially focus on reaching parents of children under five who have not done their jobs or missed out on fears of an outbreak in the capital.
The NHS currently provides a polio jab as part of a child’s routine immunization programme. The polio vaccine consists of a six-in-one vaccination, which is given to babies at eight, 12 and 16 weeks of age.