Tag: AFM

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)
  • wild poliovirus type 2 eradicated (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, a patient with a long-standing combined immunodeficiency who was probably infected in the late 1990s (2009)
  • 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)
  • 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 three countries, Afghanistan, Nigeria, 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

The BMJ Asks If Injections Are Part of the “Mystery” of Acute Flaccid Myelitis/AFM…

Yes, the BMJ, formally the British Medical Journal, just published a piece, Are injections part of the “mystery” of acute flaccid myelitis/AFM? Is the CDC interested in finding out?

Those familiar with the BMJ understand that this is not a real editorial or article though.

It is one of their Rapid responses to another article – basically a letter to the editor. Unfortunately, some folks use these Rapid responses as evidence for their anti-vaccine talking points and arguments.

The BMJ Asks If Injections Are Part of the “Mystery” of Acute Flaccid Myelitis/AFM…

We know vaccines are not associated with AFM.

It is no mystery that AFM isn’t associated with vaccines – experts review patient vaccination records.
It is no mystery that AFM isn’t associated with vaccines – experts review patient vaccination records.

The AFM patient summary form asks for a vaccination record and current studies have found no association with recent vaccines.

“They also say that they are continuing to investigate the possibility of an association, but the AFM Patient Summary Forms that they supply to US state health departments contain no questions about injections or vaccinations.”

Allan S. Cunningham on Are injections part of the “mystery” of acute flaccid myelitis/AFM? Is the CDC interested in finding out?

We know that vaccines are not associated with AFM.

“According to patients’ vaccination records, all but one had been vaccinated according to Advisory Committee on Immunization Practices recommendations. The median interval between receipt of the last vaccination and onset of neurologic symptoms was 1.9 years (range = approximately 2 months–7 years).”

Acute Flaccid Myelitis Among Children — Washington, September–November 2016

But it is understandable that some folks are still trying hard to push the idea that vaccines are associated with AFM, as to some of them, everything is a vaccine injury.

What is really baffling though, is why does BMJ give them a platform to spread their wild ideas and misinformation?

More on the BMJ

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

What is Provocation Polio?

It is well known that you can very rarely develop polio after being vaccinated with the oral polio vaccine.

VAPP or vaccine-associated paralytic polio are cases of polio that are actually caused by the polio vaccine. That’s why many countries switch over to the inactivated form of the polio vaccine once polio is under good control.

But can you get polio after an injection?

What is Provocation Polio?

You are probably thinking, sure, if the injection is full of live polio virus, right?

But this is actually the idea behind provocation polio.

No, the injection doesn’t give you polio, but if you are already infected with polio, the idea is that getting an injection could be a risk factor for developing paralytic polio.

“Provocation poliomyelitis describes the enhanced risk of paralytic manifestations that follows injection in the 30 days preceding paralysis onset.”

Plotkin’s Vaccines

Remember, most people with polio don’t actually have any symptoms, although some do have flu-like symptoms. And fewer than 1% develop paralysis or weakness when they have polio. Although that doesn’t sound like a lot, during a polio epidemic, when a lot of kids are getting polio, the cases of paralytic polio quickly add up.

What else can provoke paralytic polio?

  • strenuous exercise (paralytic polio)
  • tonsillectomy (bulbar polio)

So how does an injection provoke paralytic polio?

“Skeletal muscle injury induces retrograde axonal transport of poliovirus and thereby facilitates viral invasion of the central nervous system and the progression of spinal cord damage.”

Gromeier et al on Mechanism of Injury-Provoked Poliomyelitis

Injury to a muscle by the needle is thought to have allowed the polio virus to move through the nerves in the area to the spinal cord, as long as the polio virus was already in their blood. How do we know it was the needle and not the vaccine itself? In experiments, they injected saline, and not an actual vaccine.

Is this how everyone developed paralytic polio?

The issue of provocation polio was discussed at the The First International Conference on Live Polio Vaccines in 1959.
The issue of provocation polio was discussed at the The First International Conference on Live Polio Vaccines in 1959.

No.

Remember, kids didn’t get many vaccines around the time we were seeing polio outbreaks in the 1940s and 50s, although other injections, like penicillin were also thought to provoke paralytic polio.

Why were they getting penicillin? Often to treat congenital syphilis.

During outbreaks of paralytic polio in London in the late 1940s, fewer than 10% were related to recent injections.
During outbreaks of paralytic polio in London in the late 1940s, fewer than 10% were related to recent injections.

And although they went so far as to delay vaccines during outbreaks and to not do tonsillectomies during the summer, when polio outbreaks were more common, kids still got paralytic polio.

Could Provocation AFM Be a Thing?

Have you guessed why some folks are talking about provocation polio again, even though we are on the verge of eradicating polio?

“Seizing on a 2014 historical perspective piece on a phenomenon known as “polio provocation” in the highly respected medical journal, The Lancet, anti-vaccine forces have attempted to link the recent AFM cases (as they attempt to do with many other medical occurrences) to childhood vaccinations.”

Dr. Amesh Adalja on Clusters of polio-like illness in the US not a cause for panic

That’s right, they think that since provocation polio explained some cases of paralytic polio, then vaccines must be associated with AFM.

While it is not a bad idea, the problem with it is that vaccines are not associated with AFM.

“…is there any relationship between vaccination status and a developing acute flaccid myelitis? Meaning, are vaccines a risk factor? And the data so far says no, the overwhelming number of children who have gotten AFM have had no recent vaccination of any kind or vaccine exposure. These cases over these years have been happening before flu season and flu vaccination starts, which is one of the questions that comes up, and there hasn’t been any pattern to vaccine exposure of any kind in developing AFM. So far, we have not found a link between the two.”

Benjamin Greenberg, MD on 2018 Podcast on Acute Flaccid Myelitis

For vaccines to provoke AFM, you would have to have gotten a recent vaccine.

It is no mystery that AFM isn’t associated with vaccines – experts review patient vaccination records.
It is no mystery that AFM isn’t associated with vaccines – experts review patient vaccination records.

We aren’t seeing that and anything else all of the kids with AFM had in common that might provoke paralysis, like acupuncture, cupping,  or dry needling, would likely have come out in epidemiological reports.

More on Provocation Polio and AFM

 

Why Do Some People Think That Vaccines Cause AFM?

So we know that vaccines don’t cause acute flaccid myelitis.

Consider a five-year-old in Maryland who recently came down with symptoms of AFM.

Was he recently vaccinated?

Nope. It had been some time since his four-year-old vaccines. Almost a year. And he had not gotten a flu vaccine yet.

What he did have were worsening symptoms about two weeks after he had seemed to get over a cold, something he has in common with most other kids with AFM.

“To try to pin a tragic yet uncommon neurological condition caused by enteroviruses on vaccines is dangerous and puts more kids at risk.”

Scott Krugman, MD

As with this case, the CDC reports no correlation with vaccines in the cases that they have investigated.

And remember, some of these kids have been unvaccinated!

That makes you wonder why some folks actually think that vaccines are associated with AFM, doesn’t it?

Why Do Some People Think That Vaccines Cause AFM?

That’s right, as you are likely suspecting, the usual suspects are pushing anti-vaccine propaganda and promoting the idea to scare parents away from vaccinating and protecting their kids.

“…there are many other reasons to suspect vaccine-related mechanisms of causation for AFM in the U.S., a primary one being that the scientific literature has documented paralysis as an adverse reaction to vaccination for decades!”

The Non-Polio Illness That “Looks Just Like Polio” by Lyn Redwood, RN, MSN, President, Children’s Health Defense

If any of these kids had recently gotten the oral polio vaccine, then sure, an adverse reaction to the vaccination would be at the top of the list of possible causes. After all, we know that VAPP can occur after OPV, but that vaccine hasn’t been used in the United States since 2000, when we switched to IPV.

Why do these folks think that they have it all figured out?

Vaccines are not causing AFM because of needle puncture wounds or tonsillectomies.
Vaccines are not causing AFM because of needle puncture wounds or tonsillectomies.

The AFM outbreaks happen at the beginning of the school year, when kids are all getting their shots, right?

Nope. They happen during the summer and early fall, peaking in August. And despite what some folks think, most parents don’t wait until the end of summer, just before school starts, to vaccinate their kids. Plus, most kids don’t even need vaccines before the start of the school year. Kids typically only get vaccines before starting kindergarten and middle school.

But the outbreaks do coincide with the when kids get their flu shots, right?

How many kids get flu shots in June and July?

If it was flu shots, the peak would be in October and November, when most kids get their flu shots and we would continue to see cases through December and January.

Many anti-vaccine websites and Facebook groups are pushing the idea that vaccines cause AFM.
Many anti-vaccine websites and Facebook groups are pushing the idea that vaccines cause AFM.

Of course, there is absolutely no evidence that flu vaccines, or any other vaccines, cause AFM.

What about the journal article that Brandy Vaughan posts as evidence?

“By reviewing vaccine-associated inflammatory diseases of the central nervous system, this study describes the current knowledge on whether the safety signal was coincidental, as in the case of multiple sclerosis with several vaccines, or truly reflected a causal link, as in narcolepsy with cataplexy following pandemic H1N1 influenza virus vaccination.”

Vaccine-associated inflammatory diseases of the central nervous system: from signals to causation

Even if you just read the abstract, as many folks do, you get a good idea where they are going with the article. It talks about how the claims of an association between multiple sclerosis and vaccines were proven to be purely coincidental.

Remember, correlation does not imply causation.

With AFM, you don’t even have much correlation to imply causation though!

Most cases occur just before we start giving flu vaccines and they don’t occur every year or in every state.

But doesn’t the article mention myelitis?

“Most of the published associations are based on individual case reports or small series of patients.”

Vaccine-associated inflammatory diseases of the central nervous system: from signals to causation

It does mention myelitis, just like it mentions MS – where an association has been shown to be purely coincidental.

Remember, case reports are not good evidence.

“…there are many other reasons to suspect vaccine-related mechanisms of causation for AFM in the U.S., a primary one being that the scientific literature has documented paralysis as an adverse reaction to vaccination for decades!”

The Non-Polio Illness That “Looks Just Like Polio” by Lyn Redwood, RN, MSN, President, Children’s Health Defense

But isn’t acute flaccid myelitis listed as a possible side affect in the package inserts for our vaccines?

Uh, TRANSVERSE myelitis and ACUTE DISSEMINATED ENCEPHALOmyelitis are not the same as acute flaccid myeltitis.
Uh, TRANSVERSE myelitis and ACUTE DISSEMINATED ENCEPHALOmyelitis are not the same as acute flaccid myelitis.

While it should be clear that AFM isn’t the same as ADEM and TM, it is very important to understand that even when those other conditions are listed in a package insert, it is in the section that is marked “without regard to causality.”

This isn’t evidence that vaccines cause AFM!

But didn’t the BMJ publish a study about Vaccines and the U.S. Mystery of Acute Flaccid Myelitis?

BMJ seems to allow anyone to publish responses to their articles online...
BMJ seems to allow anyone to publish responses to their articles online…

Nope. What they did is let someone publish what is essentially an online letter to the editor. And anti-vaccine folks are spreading it around like it is an actual BMJ study…

Surprised?

You shouldn’t be.

This is how anti-vaccine propaganda works.

Why are vaccine injury lawyers talking about AFM?
Why are vaccine injury lawyers talking about AFM?

It’s no coincidence that anti-vaccine folks are trying so hard to associate the outbreaks of AFM with vaccines. What better way to scare folks and make them think that vaccines are dangerous?

AFM is all that anti-vaccine folks are talking about these days...
AFM is all that anti-vaccine folks are talking about these days…

How are ‘we’ working on a vaccine for AFM if we don’t even know what causes AFM???

But that’s how many anti-vaccine folks think. Everything is a vaccine injury. Everything is a conspiracy.

Don’t believe them. Vaccines are safe and necessary.

More on Anti-Vaccine Propaganda About AFM

 

Do Vaccines Cause Acute Flaccid Myelitis?

Breaking News – 80 cases of AFM in 25 states have been confirmed so far this year, and are among 219 cases that are 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 November 6, 2018