Tag: AFP

Milestones Towards the Eradication of Polio

There is a lot more interest in polio these days, but not because we are close to eradicating this deadly disease, but rather because of the emergence of cases of acute flaccid myelitis (AFM).

Although the cases have a different cause, the symptoms of AFM are the same that we used to see during the outbreaks of polio that used to hit each summer in the pre-vaccine era.

Polio

Surprisingly, in most people, the poliovirus doesn’t actually cause any symptoms. They simply have an asymptomatic infection.

In some others, the poliovirus causes flu-like symptoms, including a fever, sore throat, nausea, and a headache – symptoms that last about 3 to 5 days.

Much more rarely, the poliovirus causes meningitis or paralysis.

It is these cases of paralytic polio that most people are aware of and that panicked parents during summers in the 1940s and 50s.

In addition to respiratory problems (think iron lungs), polio causes muscle atrophy.
In addition to respiratory problems (think iron lungs), polio causes muscle atrophy. (CC BY-NC 4.0)

After having flu-like symptoms, those kids who would develop paralytic polio can develop pain and then flaccid paralysis.

“The most severe form, paralytic poliomyelitis, which is seen in less than 1% of patients, presents as excruciating episodes of pain in back and lower limbs. In children, the disease may present in biphasic form—a period of prodrome followed by a brief symptom-free period of 7 to 10 days and then appearance of asymmetrical paralysis of limbs. Flaccid paralysis is the hallmark with loss of deep tendon reflexes eventually.”

Mehndirattta et al on Poliomyelitis Historical Facts, Epidemiology, and Current Challenges in Eradication

Of course, polio wasn’t always called polio.

Other names have included infantile spinal paralysis, infantile paralysis, Heine-Medin disease, poliomyelitis anterior acuta, and acute anterior poliomyelitis.

The first use of the name “polio” came from Adolph Kussmaul, with his use of the term poliomyelitis anterior acuta, which was derived from the Greek polios “grey” and myelos “marrow” and itis “inflammation.” It was because he knew that it was caused by inflammation of the spinal cord gray matter, even if he didn’t know why.

Polio History

Polio didn’t just suddenly appear in the middle of the 20th century though, it was likely around for ages.

That this Ancient Egyptian priest's leg is smaller than the other and he uses a staff to walk suggests that he could have had polio.
That one of this Ancient Egyptian priest’s legs is smaller than the other and he uses a staff to walk could suggest that he had polio.

In addition to an Egyptian funeral stele (a stone slab used as a monument) portraying Roma the Doorkeeper from 1500 BCE that suggests he had paralytic polio, archeologists have found evidence of polio in skeletons as far back as the Neolithic period.

A medical book from 1789 likely describes people with polio.
A medical book from 1789 likely describes people with polio.

Still, we don’t really know how long polio has been around and we don’t know why we began to see more cases in the mid-20th Century, although there are theories, including, ironically, about hygiene. While we often credit improved sanitation and hygiene for helping to reduce mortality from many diseases, some think that this actually set us up for polio outbreaks, as we were no longer exposed as infants, when we still had some maternal immunity.

The one thing that we do know is that we are on the verge of eradicating polio, as there are very cases now, in just a few countries.

Polio Timeline and Milestones

In addition to the more ancient discoveries about polio, there is a lot to learn about vaccines and vaccine-preventable diseases if we look at the major milestones of this important disease.

Although in the end it is a success story, the road to figuring out what caused polio symptoms and how polio could be prevented was very long.

  • Michael Underwood describes what is thought to be paralytic polio in his book A Treatise on the Diseases of Children, with General Directions for the Management of Infants from Birth  in a section on “Debility of the Lower Extremities” (1789)
  • first reported outbreak of polio in Worksop, England (1835)
  • Jacob von Heine, head of an orthopedic hospital in Germany, publishes a monograph that describes 29 cases of paralytic polio, and actually attributes the condition to inflammation of the anterior horns of the spinal cord, although the cause was still not known (1840)
  • first use of the term poliomyelitis by Adolph Kussmaul (1874)
  • Nils August Bergenholtz reports on an outbreak of paralytic polio in Sweden (1881)
  • Karl-Oskar Medin, a pediatrician who reported on a polio epidemic in Sweden (1887), later presents his findings at the Tenth International Conference in Berlin (1890)
  • the first major outbreak in the United States is documented in Rutland County, Vermont and causes 132 cases of paralysis and 18 deaths (1894)
  • Ivar Wickman tracks cases of polio during an epidemic in Sweden in 1905 and was the first to suggest that polio was contagious and that you could get it from “those afflicted with the abortive type” (1907)
  • although they don’t actually identify the poliovirus, Dr. Karl Landsteiner and Dr. Erwin Popper  identify that a virus causes polio when they inject material from the spinal cord of a child who had recently died with polio into the peritoneum of two monkeys, both of which soon developed paralytic polio (1908)
  • Simon Flexner, first discovers polio antibodies (1911), but unlike other researchers at the time, pushes the theory that polio was spread by the olfactory route, instead of the fecal-oral route, which was why we saw the development of nose sprays, etc., to try and prevent polio, none of which worked of course
  • a large polio epidemic in the United States causes at least 27,000 cases and 6,000 deaths (1916)
  • Philip Drinker and Louis Agassiz Shaw invent the first iron lung, the Drinker respirator (1929)
  • Frank M. Burnet and Jean Macnamara proposed that there were antigenically different strains of poliovirus (1931)
  • John R. Paul and James D. Trask help figure out how polio was spread by identifying the polio virus in human waste and sewage samples (1932)
  • Maurice Brodie and John Kolmer have unsuccessful field trials of early polio vaccines, including allergic reactions and vaccine induced polio because of poor attenuation (1935)
  • Sister Elizabeth Kenny establishes a clinic in Australia to treat polio survivors (1932) and later publishes her treatment recommendations, Infantile Paralysis and Cerebral Diplegia (1937)
  • the National Foundation for Infantile Paralysis is founded by FDR to stop polio (1937)
  • the first March of Dimes fundraisers to stop polio (1938)
  • Carl Kling found traces of the poliovirus in the Stockholm sewage system (1942)
  • the Sister Kenny Institute is built in Minneapolis, as her treatment methods become widely accepted after years of controversy (1942)
  • the U.S. Army Neurotropic Virus Commission, including Albert Sabin, gets a grant from the NFIP to study polio in North Africa (1943)
  • Isabel Morgan actually developed the first inactivated polio vaccine, but only tested it on monkeys (1949)
  • John Enders, with T. H. Weller and F. C. Robbins, received the Nobel Prize in 1954 for their work on the cultivation of the poliomyelitis viruses (1949)
  • David Bodian creates the monkey model using field isolates of poliovirus and with Jonas Salk, identifies the three poliovirus serotyes (1950s)
  • Hilary Koprowki develops the first oral, live polio vaccine, (1950) although Sabin’s vaccine eventually gets licensed because it is thought to be less neurovirulent in monkeys and undergoes more testing
  • there are 58,000 cases of paralytic polio in the United States (1952)
  • Renato Dulbecco, with Marguerite Vogt, successfully grows and purifies polio virus (1952)
  • the Polio Pioneers vaccine field trial, led by Thomas Francis Jr.,  that proves that Jonas Salk’s polio vaccine is safe and effective begins (1954)
  • Jonas Salk gets approval for his polio vaccine (1955)
  • improperly inactivated polio vaccine from Cutter Laboratories (Cutter Incident) causes 40,000 cases of polio, 200 cases of paralysis, and kills ten people (1955)
  • Albert Sabin develops the first live, oral polio vaccine, which replaced Jonas Salk’s inactivated polio vaccine (1961)
  • that polio survivors can develop new, late complications or post-polio syndrome begins to get reported (1969)
  • last endemic case of polio in the United States (1979)
  • the National Foundation for Infantile Paralysis officially changes its name to the March of Dimes Birth Defects Foundation (1979)
  • the World Health Assembly adopts a resolution for the worldwide eradication of polio by 2000 and the the Global Polio Eradication Initiative is launched (1988)
  • last imported case of polio in the United States (1993)
  • the WHO Region of the Americas is declared polio free (1994)
  • “last” case of VAPP that was acquired in the United States (1999)
  • last case of wild poliovirus type 2 (1999)
  • the WHO Western Pacific Region is declared polio free (2000)
  • the United States switches back to using the an inactivated polio vaccine because of concerns over VAPP (2000)
  • the WHO European Region is declared polio free (2002)
  • outbreak of vaccine derived polio among a group of unvaccinated Amish in Minnesota (2005)
  • last case of VAPP that was acquired outside the United States, an unvaccinated 22-year-old U.S. college student who became infected with polio vaccine virus while traveling in Costa Rica in a university-sponsored study-abroad program (2005)
  • last case of VAPP in the United States, a patient with a long-standing combined immunodeficiency who was probably infected in the late 1990s (2009)
  • last case of type 3 poliovirus (2012)
  • seasonal reports of acute flaccid myelitis in the late summer and early fall, which might be caused by a non-polio enterovirus, are reminiscent of polio epidemics in the early part of the 20th century (2014)
  • type 2 poliovirus eradicated (2015)
  • Bob Sears says that it is okay to delay the polio vaccine on his alternative vaccine schedule because “we don’t have polio in the United States” (2015)
  • a global switch from trivalent OPV to bivalent OPV in routine immunization programs (2016)
  • polio remains endemic in just two countries, Afghanistan and Pakistan (2018)

So it should be clear, that despite what some folks think, polio wasn’t conquered overnight. And Salk and Sabin obviously had a lot of help, although those are the names we most commonly hear connected with polio eradication.

“Until poliovirus transmission is interrupted in these countries, all countries remain at risk of importation of polio, especially vulnerable countries with weak public health and immunization services and travel or trade links to endemic countries.”

Global Polio Eradication Initiative on Endemic Countries

And to be clear, polio hasn’t yet been conquered.

There is still some work to do unless we want to see cases of polio and paralytic polio return.

That’s why it is important that you don’t skip your child’s vaccines, even for diseases that we don’t have in the United States anymore.

More on the History of Polio

Is AFM a Form of Transverse Myelitis?

Acute Flaccid Myelitis (AFM) is a form of acute flaccid paralysis.

“AFM can be difficult to diagnose because it shares many of the same symptoms as other neurologic diseases, like transverse myelitis and Guillain-Barre syndrome. With the help of testing and examinations, doctors can distinguish between AFM and other neurologic conditions.”

About Acute Flaccid Myelitis

AFM is not transverse myelitis, Guillain-Barre syndrome (GBS), or Acute Disseminated Encephalomyelitis (ADEM) though, although anti-vaccine folks are trying hard to make a connection.

Is AFM a Form of Transverse Myelitis?

AFM is similar to transverse myelitis, in that they both affect a person’s spinal cord, but a big difference is that TM results from “an immune-mediated inflammatory attack of a person’s spinal cord.”

“This report and others indicate that AFM represents a unique subset of acute flaccid paralysis distinct from GBS and transverse myelitis. GBS typically presents with an ascending paralysis and can be associated with facial paralysis and sensory symptoms. Children with transverse myelitis have weakness and prominent sensory loss, often manifest as a spinal sensory level. By contrast, the majority of children with AFM have focal, poliomyelitis-like spinal cord paralysis with minimal or no sensory symptoms.”

Recognition and Management of Acute Flaccid Myelitis in Children

And AFM has different symptoms from both TM and GBS.

So why try to connect AFM with TM, GBS, and ADEM? Because they think that vaccines cause TM, GBS, and ADEM.

They don’t. Just like vaccines don’t cause AFM.

There is no proof in package inserts that vaccines cause AFM.
There is no proof in package inserts that vaccines cause AFM.

But can’t you find some of these things listed in the package insert for some vaccines?

Yes, but when mentioned in a vaccine’s package insert, like for autism, SIDS, or meningitis, it is in the section where it is clear that it is “without regard to causality.”

AFM is not transverse myelitis and neither are caused by vaccines.

We will hopefully learn what is causing the latest cases of AFM soon.

More on AFM and Transverse Myelitis

Do Vaccines Cause Acute Flaccid Myelitis?

Breaking News – 158 cases of AFM in 36 states have been confirmed so far this year, with an additional 153 cases under investigation.

Since 2014, we have seen several outbreaks of acute flaccid paralysis (the sudden onset of weakness in one or more arms or legs) across the United States.

Why?

We don’t know, except we do know that these folks don’t have polio, even though folks continue to get confused because the kids are described as having a “polio-like” disease. Every case undergoes extensive testing, including testing for polio and other viral infections.

Do Vaccines Cause Acute Flaccid Myelitis?

Tragically, like some other conditions of unknown cause, some people have grasped onto the idea that AFP could be caused by vaccines.

“Of 14 patients with available information, 12 had previously received polio vaccine; one child and one adult were unvaccinated because of personal belief exemptions.”

Acute Flaccid Paralysis with Anterior Myelitis — California, June 2012–June 2014

It shouldn’t be surprising that there is absolutely no evidence that this is any type of vaccine injury.

Of nearly 350 cases of the acute flaccid myelitis (AFM), or the subtype of AFP that we have been seeing since 2014, we know that:

  • most cases occur in children
  • they have a magnetic resonance image (MRI) showing spinal cord lesion largely restricted to gray matter and spanning one or more vertebral segments
  • AFM can be caused by viruses, environmental toxins, and genetic disorders, although no common etiology has been found in recent cases
  • cases are occurring sporadically – after 120 cases in 34 states in 2014, there were only 24 cases in 17 states in 2015, but then 149 cases in 39 states in 2016 and 33 cases in 16 states in 2017. And there have been at least 62 cases in 22 states in 2018.
  • most cases occur in the late summer and early fall
  • most had symptoms of a preceding viral illness, including respiratory symptoms or diarrhea
  • some were unvaccinated
  • the ages of affected children has ranged from 5 months to 20 years
  • some patients have recovered, while others have persistent paralysis
  • there has been at least one death
  • some, but not all, were positive for enterovirus D68
  • in Colorado this year, 9 of 14 cases were linked to EV-A71 infections
  • although there was a national outbreak of EV-D68 in 2014 that coincided with the first AFM cases, we didn’t see this kind of outbreak in the following years

So what’s causing these kids, with a median age of about 7 years, to develop acute flaccid myelitis?

We don’t know, but there is certainly no reason to think that it could be a vaccine, as some anti-vaccine folks suggest.

For one thing, several of the kids were completely unvaccinated!

And then, if it was a vaccine, why the seasonal pattern?

Would a vaccine injury have such a seasonal pattern – even skipping a year?
Would a vaccine injury have such a seasonal pattern – even skipping a year?

And why don’t cases occur in all states and at the same rates each year?

Also, why the big range in ages? After all, what vaccines do a 5 month old and a 20 year old have in common?

And the CDC has been looking at all possible causes.

“Our medical team has been reviewing vaccine records when available during this year’s investigation and do not see a correlation.”

Kristen Nordlund, CDC spokeswoman

Acute flaccid myelitis is not caused by vaccines. Hopefully we will soon find out what really is causing it and can figure out how to prevent it.

Want to prevent a type of acute flaccid paralysis right now?

Get vaccinated!

While AFM is a type of non-polio AFP, we have long had a vaccine that can prevent polio, which also causes acute flaccid paralysis.

More on Vaccines and Acute Flaccid Paralysis

Updated December 10, 2018

Did Modern Ventilators Replace the Iron Lung for Folks with Polio?

Believe it or not, some folks don’t think that vaccines work and that some diseases, like smallpox and polio, never really went away.

Residual paralysis that lasts more than 60 days is the strongest predictor that a case is really polio, which is why, in addition to testing for polio virus, the 60 day standard is used.
Want the real truth? Residual paralysis that lasts more than 60 days is the strongest predictor that a case is really polio, which is why, in addition to testing for polio virus, the 60 day standard is used.

Of course, they have special little theories for how this all works.

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.

In fact, in the 1940s and 1950s, there were whole hospital wards full of polio patients in iron lungs.

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.

Iron Lung

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.

Thanks to vaccines, most folks will only see an iron lung in a museum and read about polio in history books.
Thanks to vaccines, most folks will only see an iron lung in a museum and read about polio in history books. Photo by Oscar Tarragó, M.D., M.P.H.

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.

Vaccines work. Polio is almost eradicated.

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.

More on Ventilators and Iron Lungs