Tag: Albert Sabin

The Myth That Polio Only Went Away Because They Changed the Way It Was Diagnosed

Have you heard this one?

“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.”

So that’s why polio went away?

It wasn’t the vaccine?

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.

Why?

“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.

That’s how they work to scare parents and hope that their anti-vaccine myths and misinformation can win out over the truth that vaccines work and that they are safe and necessary.

“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

There is no conspiracy.

Think about it.

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?

After the switch to the Sabin vaccine, polio was on its way to being eliminated in the United States.
After the switch to the Sabin vaccine, polio was on its way to being eliminated in the United States, although there was an uptick in 1959, before we made the switch.

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.

More on Polio Myths and Conspiracies

Is There a DDT-Polio Connection?

Polio is caused by one of three wild-type polio viruses.

Of course, anti-vaccine folks like to push misinformation about polio being caused by a lot of other things, from poor hygiene and eating too much white bread to having a tonsillectomy or being exposed to pesticides, like DDT.

“Williams describes the many blind alleys and false leads of the early days of polio research, when doctors, scientists, and public health officials were convinced that the disease was transmitted by bedbugs, budgies, cats, and flies, or caused by seafood, cow’s milk, jimson weed, fruit, vegetables, and DDT…”

Paul Offit on Polio Revisited

Not surprisingly, it is DDT that they like to focus on the most.

They even have graphs that they think correlate the rise in production of DDT with an “Age of Polio.”

Polio Is Good For Meeee!

First things first though.

Why do anti-vaccine folks want to connect DDT and polio?

It’s simple.

If the polio virus doesn’t cause polio (germ theory denialism), then you can’t really expect the polio vaccine to prevent polio, now can you?

The DDT-Polio Connection?

There actually is a bit of a connection between polio and DDT, but not the one anti-vax folks think.

Wait, what?

No, DDT didn’t cause polio.

“Between the end of World War II and the early 1950s, researchers, municipal officials, and individuals from Georgia to California employed DDT to stop polio by killing flies, a suspected but debated actor in the disease’s transmission.”

Conis on Polio, DDT, and Disease Risk in the United States after World War II 

Yes, many towns would routinely spray with DDT after a polio epidemic came to town because they didn’t yet know what did cause polio.

For example, in May 1946, “sections of the city were blanketed” with DDT as they sought to stop the source of a polio epidemic in San Antonio, which they thought might be a “tropical mosquito.”

Even the schools were closed in San Antonio when polio came to Texas in 1946.
Even the schools were closed in San Antonio when polio came to Texas in 1946. And they stayed closed for the last few weeks of the Spring term!

See the connection now?

Polio first. DDT spraying after.

This idea is especially easy to see when you understand that there were many polio outbreaks and epidemics in the late 19th and early 20th century, well before DDT was discovered to be an effective insecticide in the early 1940s.

And the spraying mostly stopped before the polio outbreaks stopped.

In 1951, although he wasn’t yet sure how the polio virus spread, Dr. Sabin did know it came from “human feces derived from patients and healthy carriers,”  and he declared that there was “general agreement that there is no justification for initiating emergency insect control measures in the hope of stopping a poliomyelitis epidemic.”

“It is perhaps an established epidemiological principle that epidemiological probability must be compatible with bacteriologic (or virologic) possibility, particularly when the epidemiological probabilities lend themselves to several alternative explanations.”

Albert B Sabin, MD on Transmission of Poliomyelitis Virus

And even before that, the Editorial Board for the American Journal of Public Health, in 1946, said that “While municipal cleanliness and sanitation are always highly desirable, there is no reason to believe that improved methods of sewage treatment and disposal, more rigid standards for the purification of water supplies, or the dusting of DDT over a city from aeroplanes will have any measurable effect on the incidence of infantile paralysis.”

Also remember the other big reason that we saw DDT spraying in the United States – the elimination of malaria.

“The National Malaria Eradication Program, a cooperative undertaking by state and local health agencies of 13 southeastern states and the CDC, originally proposed by Louis Laval Williams, commenced operations on July 1, 1947. By the end of 1949, over 4,650,000 housespray applications had been made.”

CDC on Elimination of Malaria in the United States (1947 — 1951)

Did the spraying of DDT to eliminate the flies that transmit malaria in the southeastern United States correlate with extra cases of polio?

No.

There were big outbreaks in New York, Indiana, Ohio, and many other parts of the country that didn’t spray DDT to help fight malaria.

“The peak year for use in the United States was 1959 when nearly 80 million pounds were applied. From that high point, usage declined steadily to about 13 million pounds in 1971, most of it applied to cotton.”

EPA on DDT Ban Takes Effect

Did we stop spraying with DDT in the early 1950s because it was banned and is that why we stopped seeing so much polio?

No.

The peak year for DDT use was in 1959. Surprisingly, we don’t see that peak on any anti-vaccine graphs in 1959…

What was the peak year for polio cases? It wasn’t 1959 or 1960, as you would expect if there was a link between DDT and polio.

The peak year for polio cases was in 1952.

Although the use of DDT decreased after 1959, it was used until it was “banned” in 1972, and even then, there were exceptions for public health uses.

Explaining Polio

The polio virus causes polio.

But why?

Or at least why did we start seeing so many more cases in the late 18th through the mid 19th century, until it was controlled with our polio vaccines?

“…contrary to the prevailing “disease of development” hypothesis, our analyses demonstrate that polio’s historical expansion was straightforwardly explained by demographic trends rather than improvements in sanitation and hygiene…”

Martinez-Baker et all on Unraveling the Transmission Ecology of Polio

One rather simple and elegant explanation is that we started to get too clean, the “disease of development” hypothesis.

Improved hygiene and sanitation helped delay when kids would get polio. Remember, polio is spread by contaminated food and water through fecal-oral transmission.

So instead of routinely getting it when they were newborn babies or young infants, when they still had some protection from maternal antibodies, they got it later when they had no immunity. So polio essentially changed from an endemic disease, or something that everything got, to an epidemic form.

And now, despite the work of the anti-vaccine movement, it will hopefully soon become an eradicated form!

What to Know About The DDT-Polio Connection

DDT is a pesticide that was widely used after World War II and was sometimes sprayed in a vain attempt to keep polio outbreaks from getting out of control. That is the only connection to polio though.

More About The DDT-Polio Connection

 

Polio Vaccines

The first polio vaccines were licensed in the 1950s and ’60s by Jonas Salk and Albert Sabin.

My uncle got polio just before the vaccine was developed. He was hospitalized for six months, almost didn't survive, and lived with atrophied muscles in one of his legs.
My uncle got polio just before the vaccine was developed. He was hospitalized for six months, almost didn’t survive, and lived with atrophied muscles in one of his legs.

Together, they have helped us get to the point where we are close to eradicating polio.

We are not quite there yet though.

Today, in the United States, after thirty years of using the live, oral polio vaccine, we are once again using polio shots because of the risk of VAPP.

Infants get their first doses at two and four months and a third dose in the primary series between six and 18 months. A booster dose is give between four to six years.

More on Polio Vaccines

Albert Sabin

Albert Sabin is well known as the developer of the oral polio vaccine.

In 1961, Sabin’s live, attenuated polio vaccine replaced Jonas Salk’s inactivated polio vaccine that had been in use since 1955.

Sabin's oral polio vaccine helped get us close to eradicating polio.
Sabin’s oral polio vaccine helped get us close to eradicating polio.

Although OPV is very effective and safe, because of the very small risk of vaccine-associated paralytic polio (VAPP), many polio-free, industrialized countries eventually switch back to IPV.

The United States switched back to IPV in 2000.

More on Albert Sabin