It’s true, polio has been eliminated in the United States.
But that doesn’t mean that we can stop vaccinating kids against polio yet.
Why Do We Still Vaccinate If Polio Has Been Eliminated?
For one thing, the last polio case in the United States was a lot more recent than 40 years ago.
What happened 40 years ago?
That was when we had the last endemic case of polio in the United States, in 1979. After that, in addition to cases of VAPP, there were at least 6 cases of imported paralytic poliomyelitis. In fact, the last case of wild polio in the United States was in 1993, just 26 years ago.
And just ten years ago, in 2009, was the very last case of VAPP, a patient with a long-standing combined immunodeficiency who was probably infected in the late 1990s, even though she didn’t develop paralysis until years later.
But still, why couldn’t we stop vaccinating against polio in the United States, even though polio isn’t eradicated yet? After all, we stopped using the smallpox vaccine in 1972, before smallpox was declared eradicated (1980).
While that is true, smallpox isn’t as contagious as polio and there hadn’t been a case of smallpox in the United States for over 30 years when we stopped using the vaccine.
Until wild polio is eradicated and the oral polio vaccine isn’t used anymore (OPV switch), we must continue to vaccinate against polio to prevent new outbreaks.
That is the polio eradication and endgame strategic plan.
Over the next few years, the world will hopefully switch to using just the injectable form of the polio vaccines, which eliminates the risk of VAPP.
But if we are so close, why not just stop vaccinating in those parts of the world that don’t have polio?
Because we are so close to eradicating polio.
Why take the risk of polio spreading from one of the remaining endemic countries, paralyzing kids, and putting eradication efforts further behind?
Did Modern Ventilators Replace the Iron Lung for Folks with Polio?
In addition to thinking that we just change the names of diseases when we want them to go away, some folks think that we don’t see anyone in iron lungs anymore, not because polio has been eliminated, but because modern ventilators simply replaced the iron lung.
Is that true?
The iron lung, invented in 1927, helped people with polio breath.
Unlike most of today’s ventilators, the iron lung is a negative pressure ventilator. In contrast, most modern ventilators, the ones that you see people hooked up to with a tube going down to their lungs, are positive pressure ventilators.
What’s the difference?
A positive pressure ventilator pushes air into your lungs. They are useful when you have a lung disease or simply can’t breath on your own.
When people had polio, there usually wasn’t anything wrong with their lungs – it was their chest muscles and diaphragm that were the problem. So the negative pressure in the iron lung would compress and decompress their chest.
One benefit of the iron lung included that it was less invasive than ventilating someone through a tracheostomy, which became an option in the 1960s. While many new options became available for those needing long term ventilation since then, including noninvasive positive pressure ventilation, some still like to use their iron lungs.
And while it is true that they don’t make them anymore, iron lungs have not disappeared. There are some folks with polio that still use them.
But what if someone developed polio now, would they be put in an iron lung?
No, they wouldn’t. For one thing, they don’t make iron lungs anymore. Instead, they would likely use mouth intermittent positive pressure ventilation.
Still, we don’t see a lot of folks getting diagnosed with polio, needing to use mouth intermittent positive pressure ventilation, instead of iron lungs these days. And that’s because we don’t see a lot of folks getting diagnosed with polio.
What to Know About Polio, Modern Ventilators and Iron Lungs
Although some people with polio are still using their iron lungs, the main reason we don’t see more people with polio needing to use iron lungs or modern ventilators is simply because polio is almost eradicated.
“Before the vaccine was developed, the diagnosis of polio required 24 or more hours of paralysis. After the vaccine release, the diagnosis changed to at least 60 days of paralysis. As you can imagine, cases of polio dropped significantly.”
The Myth That Polio Went Away Because They Changed the Diagnostic Criteria
In 1952, there were 21,000 cases of paralytic polio in the United States.
But were there really?
Didn’t they change the way they diagnosed polio a few years later, right after the first polio vaccines came out, making it less likely that folks would be diagnosed with polio?
The original diagnostic criteria for polio came from the World Health Organization and included:
“Signs and symptoms of nonparalytic poliomyelitis with the addition of partial or complete paralysis of one or more muscle groups, detected on two examinations at least 24 hours apart.”
It changed in 1955 to include residual paralysis 10 to 20 days after onset of illness and again 50 to 70 days after onset.
“In the past children’s paralysis was often not correctly diagnosed as polio. Stool samples need to be analyzed to be able to distinguish paralytic symptoms from Guillain-Barré Syndrome, transverse myelitis, or traumatic neuritis.”
Polio – Data Quality and Measurement
But you coulld’t just use stool samples, as many kids might have recently had non-paralytic polio, and could test positive for polio (false positive test), but have another reason to have paralysis.
“Isolation of poliovirus is helpful but not necessary to confirm a case of paralytic poliomyelitis, and isolation of poliovirus itself does not confirm diagnosis.”
Alexander et al. on Vaccine Policy Changes and Epidemiology of Poliomyelitis in the United States
Since polio causes residual paralysis, the new diagnostic criteria helped to make sure that kids were diagnosed correctly.
Did We Overestimate the Number of Kids with Polio?
Some folks think that since we changed the criteria, we overestimated the number of kids with polio in the years before the vaccine came out.
Most of this idea seems to come from a panel discussion in 1960 by critics of the original polio vaccine, The Present Status of Polio Vaccines, including two, Dr. Herald R. Cox and Dr. Herman Kleinman, who were working on a competing live-virus vaccine.
None in the group were arguing against vaccines, or even really, that the Salk polio vaccine didn’t work at all though. They just didn’t think that it was effective as some folks thought.
“I’ve talked long enough. The only other thing I can say is that the live poliovirus vaccine is coming. It takes time. The one thing I am sure of in this life is that the truth always wins out.”
Dr. Herald R. Cox on The Present Status of Polio Vaccines
Dr. Cox did talk a lot about the oral polio vaccine. He talked about successful trials in Minneapolis, Nicaragua, Finland, West Germany, France, Spain, Canada, Japan, and Costa Rica, etc.
When anti-vaccine folks cherry pick quotes from The Present Status of Polio Vaccines discussion panel, they seem to leave out all of the stuff about how well the oral polio vaccine works.
“Since nothing is available, there seems to be no alternative but to push the use of it. I don’t think we should do so in ignorance, nor too complacently, believing that as long as we have something partially effective there is no need to have something better.”
Dr. Bernard Greenberg on The Present Status of Polio Vaccines
And of course, they did, fairly soon, switch to something better – the Sabin live-virus oral polio vaccine.
Interestingly, using the idea that we changed the diagnostic criteria to make polio go away in an argument about vaccines is known as the Greenberg Gambit.
It tells you something about anti-vaccine arguments, that these folks are misinterpreting something someone said about vaccines almost 60 years ago.
In pushing the idea that polio hasn’t been eliminated, but rather just redefined, they also miss that:
But isn’t polio still around and just renamed as transverse myelitis, Guillain-Barré syndrome (GBS), and aseptic meningitis?
Let’s do the math.
Using the adjusted numbers in the The Present Status of Polio Vaccines discussion, there were at about 6,000 cases of paralytic polio in the United States in 1959.
While 3,000 to 6,000 people in the United States develop Guillain-Barré syndrome each year, the risk increases with age, and it is rare in young kids. Remember, paralytic polio mostly affected younger children, typically those under age 5 years.
“Transverse myelitis can affect people of any age, gender, or race. It does not appear to be genetic or run in families. A peak in incidence rates (the number of new cases per year) appears to occur between 10 and 19 years and 30 and 39 years.”
Transverse Myelitis Fact Sheet
Similarly, transverse myelitis is uncommon in younger children, and there are even fewer cases, about 1,400 a year.
What about aseptic meningitis? That doesn’t usually cause paralysis.
So do the math.
You aren’t going to find that many kids (remember, the incidence was 5-7 per 1,000) under age 5 years who really have “polio,” but instead, because of a worldwide conspiracy about vaccines, are getting diagnosed with transverse myelitis, Guillain-Barré syndrome (GBS), or aseptic meningitis instead.
Anyway, kids with acute flaccid paralysis are thoroughly tested to make sure they don’t have polio. And both transverse myelitis and Guillain-Barré syndrome have different signs and symptoms from paralytic polio. Unlike polio, which as asymmetric muscle atrophy, the atrophy in transverse myelitis and Guillain-Barré syndrome is symmetrical. Also, unlike those other conditions that cause AFP, with polio, nerve conduction velocity tests and electromyography testing will be abnormal. Plus, polio typically starts with a fever. The other conditions don’t. So while these conditions might all be included in a differential diagnosis for someone with AFP, they are not usually that hard to distinguish.
“Each case of AFP should be followed by a diagnosis to find its cause. Within 14 days of the onset of AFP two stool samples should be collected 24 to 48 hours apart and need to be sent to a GPEI accredited laboratory to be tested for the poliovirus.”
Polio – Data Quality and Measurement
But why be so strict on following up on every case of AFP?
It’s very simple.
If you miss a case of polio, then it could lead to many more cases of polio. And that would tmake it very hard to eradicate polio in an area.
If anything, until the establishment of the Global Polio Eradication Initiative (GPEI) in 1988, it is thought that cases of polio and paralytic polio were greatly underestimated in many parts of the world!
And now polio is almost eradicated.
“DR. SABIN: Let us agree, at least, that things are not being brushed aside. Let us say that we might disagree on the extent to which certain things have received study. But I hope that Dr. Bodian realizes that nobody is brushing things aside. I would not have taken the trouble of spending several months studying viremia with different strains in chimpanzees and human volunteers, and viremia produced by certain low temperature mutants to correlate it with their invasive capacity, if I were merely brushing it aside.”
Live Polio Vaccines – Papers Presented and Discussions Held at the First International Conference on Live Poliovirus Vaccines
If they redefined how paralytic polio was diagnosed in 1955 as part of a conspiracy to make it look like the polio vaccines were working, then why did the number of cases continue to drop into the 1960s?
Shouldn’t they have just dropped in 1955 and then stayed at the same lower level?
And why don’t any of the folks with other conditions that cause paralysis, like transverse myelitis and Guillain-Barré syndrome (GBS) ever have polio virus in their system when they are tested?
Also, if the renaming theory explains why the polio vaccine didn’t work, then why do anti-vaccine folks also need to push misinformation about DDT and polio?
What to Know About Polio Myths and Conspiracies
The near eradication of polio from the world is one of the big success stories of the modern era, just as those who push the idea that has all been faked is a snapshot of society at one of our low points.
Breaking News – further tests have found that the person with suspected polio did not have either wild polio or vaccine-derived poliovirus (VDPV). Could it still be polio? (see below).
Polio is on the verge of being eradicated.
In 2017, there have only been 118 cases of polio in the whole world, including 22 cases of wild poliovirus in Afghanistan and Pakistan and 96 cases of vaccine-derived poliovirus (VDPV) in the Democratic Republic of Congo and Syria.
So far this year, there have only been 15 cases of polio in the whole world, including 10 cases of wild poliovirus in Afghanistan and Pakistan and five cases of vaccine-derived poliovirus (VDPV) in the Democratic Republic of Congo and Nigeria.
Is Polio Returning to Venezuela?
Most of us are aware that vaccine-preventable diseases are just a plane ride away.
We see it, or at least read about it, all of the time, as we continue to see outbreaks of measles affecting our communities.
Could polio return?
Venezuela has been polio free for nearly 30 years. The last case of a wild poliovirus infection was in March 1989. And yet ,there are now thought to be at least four cases of poliovirus, type 3 in the Delta Amacuro state of north east Venezuela, where they are also seeing cases of diphtheria and measles.
Among the polio cases is a 2-year-old boy who was unvaccinated, an unvaccinated child who lived next to him, and a partially vaccinated child 8-year-old who lived next door.
“It has been reported unofficially that it is polio vaccine virus.”
Venezuelan Society of Public Health Report
But what is the source of the polio vaccine virus?
We supposedly stopped using oral polio vaccines that can shed in January 2016, right?
Actually, we began the switch from trivalent OPV (tOPV) to bivalent OPV (bOPV) in 2016, removing the the type 2 polio virus that is most likely to cause VAPP. Making sure kids get a dose of IPV first also lowers the risk of VAPP. At least it does when kids get vaccinated according to plan.
“Other children from the same community were vaccinated in April 2018 with oral bivalent polio vaccine.”
PAHO on Epidemiological Update Detection of Sabin type 3 vaccine poliovirus in a case of Acute Flaccid Paralysis
When did the first case appear? Although we are just hearing about it now, his symptoms began in April, right around the time another child received a bivalent oral polio vaccine.
“No additional AFP cases have been identified to date through active search for AFP cases carried out in the community.”
PAHO on Epidemiological Update Detection of Sabin type 3 vaccine poliovirus in a case of Acute Flaccid Paralysis
Fortunately, in the past month, no further cases have been identified.
So what does this all mean?
For one thing, wild polio isn’t returning to Venezuela. And it doesn’t look like we will see a large outbreak of cVDPV, as there are no further cases of AFP in the area.
But it does illustrate that we can easily see a return of vaccine-preventable disease if we don’t keep vaccinating until they are eradicated. Remember, low vaccination coverage is associated with outbreaks of cVDPV. If everyone is vaccinated and protected, then they won’t get polio, whether it is wild type or shed from someone who was vaccinated.
Latest Updates on AFP in Venezuela
While a Sabin type 3 polio virus had been initially isolated from the stool samples of the unvaccinated 34-month-old boy with polio symptoms, further tests have now been completed.
“Tests carried out by the specialized global laboratory for genetic sequencing have ruled out the presence of both wild poliovirus and vaccine-derived poliovirus (VDPV). The latter- VDPV- is a Sabin virus with genetic mutations that give it the ability to produce the disease. There is no risk of spread to the community or outbreaks of polio from this case.”
So what does he have?
The possibilities are non-polio AFP, as many viruses and other diseases can cause polio-like symptoms.
So why did he have the Sabin type 3 polio virus in his stool?
It is well known that the oral polio vaccines shed. Even though he was unvaccinated, he was likely exposed to others in the community who were recently vaccinated, as it is possible to shed the vaccine virus in your stool. The attenuated (weakened) vaccine virus is unlikely to cause symptoms though, unless it develops the mutations found in VDPV strains, which this one didn’t.
“The child is being further evaluated clinically to determine alternative causes of paralysis. The final classification of the case of acute flaccid paralysis [to define whether or not it is associated with the vaccine] will be based on clinical and virological criteria assessed at 60 days after the onset of paralysis.”
So despite what folks are reporting, they didn’t say that this case couldn’t be associated with the polio vaccine. We just know that it is isn’t wild polio and the virus doesn’t have the mutations associated with cVDPV strains, which can not only cause polio symptoms, but can also spread from one person to another, causing outbreaks.
Remember, although the attenuated vaccine virus in the oral polio vaccine is unlikely to cause polio symptoms, it sometimes can, in about 1 in 2.7 million doses.
“VAPP at this time can’t be ruled out, of course, as it’s one of the possibilities.”
Global Polio Eradication Initiative
Could this child have VAPP?
“A VAPP case was most often defined as a case of acute flaccid paralysis (AFP) with residual paralysis (compatible with paralytic poliomyelitis) lasting at least 60 days, and occurring in an OPV recipient between 4 and 40 days after the dose of OPV was administered, or in a person who has had known contact with a vaccine recipient between 7 and 60–75 days after the dose of OPV was administered.”
Platt et al on Vaccine-Associated Paralytic Poliomyelitis: A Review of the Epidemiology and Estimation of the Global Burden
I guess we will find out in a few weeks, as his symptoms started at the end of April.
Still, remember that VAPP is not contagious.
What to Know About Polio Returning to Venezuela
Several cases of a vaccine strain of polio virus have been found in Venezuela, which is linked to low vaccinated levels.
We should know that vaccine-preventable diseases were rarely mild, natural immunity comes at a cost, and that those who died from smallpox, diphtheria, measles, and polio aren’t around to talk about their experiences on Facebook (survivorship bias).
We should never forget that vaccine-preventable diseases were once big killers, and the only reason some folks have grown to fear the side effects of vaccines more than the diseases they prevent, is because we don’t see those diseases very much any more. If more people skip or delay getting vaccinated, we will though.
Nelson Mandela was long imprisoned in South Africa for protesting against apartheid.
After 27 years in prison, he was elected president of the African National Congress (ANC) and eventually became the first elected President of a democratic South Africa.
A lesser known fact is that Nelson Mandela served as Chairman of the Board of Directors for The Vaccine Fund, which provides financial support to the Global Alliance for Vaccines and Immunization (GAVI).
“Giving children a healthy start in life, no matter where they are born or the circumstances of their birth, is the moral obligation of every one of us.
I find it heartbreaking that 3 million people, most of them children, die each year from diseases that we can prevent with simple, inexpensive vaccines. These are children who would have grown up to support their families, their communities, their nations. They would have been productive members of societies that are still developing and need their children to be healthy and strong.
By preventing these deaths, we not only would save children’s lives, but we also would help strengthen communities and contribute to the development of strong and prosperous nations.”
During his time working with the Vaccine Fund, from 2001 to 2004, he worked to get more and more kids vaccinated and protected against vaccine-preventable diseases.
“A world free of unnecessary disease would be a world more able to cope with the realities it cannot change. A world less burdened by preventable disease would be a world of more balance and greater opportunity for all. Because as a society we are only as strong as the sum of our parts, we all suffer loss when 25 percent of our global family is incapacitated, as it is today. We all lose because too many of our children will never have the opportunity to realize their talents, to share their unique gifts, to focus their courage, or to inspire their fellow citizens to shape a better world.”
Before his work at the Vaccine Fund, as President of South Africa, in 1996, Nelson Mandela launched the “Kick Polio Out of Africa” campaign at the Organization of African Unity (OAU) meeting in Yaoundé, Cameroon.
He also committed the OAU to regularly monitoring progress of the campaign, which helped decrease the number of countries with endemic polio in Africa from 34 to just 2 in 6 years!
And it was Nelson Mandela himself that was “hugely influential” in making sure the campaign worked.
“Children are our future, they are our best hope, their suffering our worst fear. Parents the world over will lie awake at night with fears and dreams in equal measure for what lies ahead for them. Our actions can help or hinder their development. With the resources that the world has at hand, it is possible to break the cycles of poverty and disease. Starting with immunization, we can reduce the inequities of our world and tackle today’s major epidemics, like HIV/AIDS, so that the next generation has an equal chance of life and health.
Guardians of health, we urge you to take up this challenge: we call on governments and civil groups, organizations of the United Nations system and nongovernmental organizations, philanthropists and responsible corporate citizens, to recognize immunization as a global public good. Meet your moral and financial commitments to the world’s children and make a greater investment in immunization.”
As we get closer to that goal of eradicating polio, we shouldn’t forget that his hard work helped us get there.
We also shouldn’t forget our “moral and financial commitments to the world’s children.”
Let’s continue his work to get them all vaccinated and protected.
What to Know About Nelson Mandela and His Vaccine Advocacy
Nelson Mandela believed in the importance of education, that children should be able to live free from violence and fear, and that they shouldn’t die from diseases that can be easily preventable with vaccines.
Today, in the United States, children typically get:
36 doses of 10 vaccines (HepB, DTaP, Hib, Prevnar, IPV, Rota, MMR, Varivax, HepA, Flu) before starting kindergarten that protect them against 14 vaccine-preventable diseases
at least three or four more vaccines as a preteen and teen, including a Tdap booster and vaccines to protect against HPV and meningococcal disease, plus they continue to get a yearly flu vaccine
So by age 18, that equals about 57 dosages of 14 different vaccines to protect them against 16 different vaccine-preventable diseases.
While that sounds like a lot, keep in mind that 33% of those immunizations are just from your child’s yearly flu vaccine.
Of course, kids in the United States don’t get all available vaccines and aren’t protected against all possible vaccine-preventable diseases. Some vaccines are just given if traveling to a high risk area or in other special situations.
Vaccine-preventable diseases (in the United States, children and teens are routinely protected against the diseases highlighted in bold) include:
adenovirus – a military vaccine
anthrax – vaccine only given if high risk
chicken pox – (Varivax, MMRV)
cholera – vaccine only given if high risk
dengue – vaccine not available in the United States
diphtheria – (DTaP/Tdap)
hepatitis A – (HepA)
hepatitis B – (HepB)
hepatitis E – vaccine not available in the United States
HPV – (Gardasil)
Haemophilus influenzae type b – (Hib)
measles – (MMR, MMRV)
meningococcal disease – (MCV4 and MenB and MenC)
pneumococcal disease – (Prevnar13 and PneumoVax23)
pertussis – (DTaP/Tdap)
polio – (bOPV and IPV)
Q-fever – vaccine not available in the United States
rabies – vaccine only given if high risk
rotavirus – (RV1, RV5)
rubella – (MMR, MMRV)
shingles – vaccine only given to seniors
smallpox – eradicated
tetanus – (DTaP/Tdap)
tick-borne encephalitis – vaccine not available in the United States
tuberculosis – (BCG) – vaccine only given if high risk
typhoid fever – vaccine only given if high risk
yellow fever – vaccine only given if high risk
Discontinued vaccines also once protected people against Rocky mountain spotted fever, plague, and typhus.
These vaccine-preventable diseases can be contrasted with infectious diseases for which no vaccines yet exist, like RSV, malaria, norovirus, and HIV, etc., although vaccines are in the pipeline for many of these diseases.
What To Know About Vaccine Preventable Diseases
Available vaccines are helping to eliminate or control a number of vaccine-preventable diseases, like polio, measles, and diphtheria, but a lot of work is left to be done.