Tag: John Salamone

What Happens if We Stop Using Oral Polio Vaccines?

As we occasionally hear reports of vaccine derived polio, it shouldn’t be surprising that anti-vaccine folks are calling for the end of all use of the oral polio vaccines that can trigger these cases.

Do you recognize the NVIC and ICAN? Think Barbara Loe Fisher and Del Bigtree... and ask them why they want to bring back polio. — Do you recognize the NVIC and ICAN? Think Barbara Loe Fisher and Del Bigtree… and ask them why they want to bring back polio.

Got any idea of what would happen if anyone listened to them?

What Happens if We Stop Using Oral Polio Vaccines?

Believe it or not, a plan is already in place to stop using oral polio vaccines.

So why haven’t we done it yet?

“In April 2016 a switch was implemented from trivalent OPV to bivalent OPV in routine immunization programmes. Following WPV1 and WPV3 eradication, use of all OPV in routine immunizations will be stopped.”
OPV Cessation

It is obviously because we haven’t yet eradicated wild polio!

“The GPEI’s achievements are evident not just in the retreat of WPV to geographic corners of the world, but also in the successive elimination of WPV types. In 2015, WPV type 2 was declared eradicated; WPV type 3 has not been seen since 2012; and while WPV1 has yet to be interrupted, its incidence has been reduced by over 90% since 2014.”
Polio Endgame Strategy 2019–2023

We are very close though.

“In impoverished communities with substandard sanitation and living conditions, vaccine strain poliovirus can contaminate water sources used for bathing and drinking, which can lead to more cases of vaccine strain polio paralysis,” said Barbara Fisher, co-founder and president of the National Vaccine Information Center. “Until polio eradication campaigns stop using live oral polio vaccine, the vaccine strain polio virus will continue to cripple children and adults.”
Vaccination-wary groups call for halt of oral polio vaccine

But if we stopped using oral polio virus vaccines before polio was eradicated, we would simply start seeing more cases of wild polio. And they would be at much higher levels than the vaccine derived cases we are seeing now.

“While over 18 million people who would have been paralysed by polio are walking today as a result of the eradication programme, we have not yet reached zero – and our mission to reach every last child remains as urgent as ever. If we stop our efforts now, within ten years we could see as many as 200,000 new cases each year, all over the world. Simply put, children everywhere remain at risk until polio is eradicated.”
Polio Endgame Strategy 2019–2023

Is that what Barbara Loe Fisher is proposing?

The Endgame Plan 2013-2018 succeeded in certifying South-East Asia (SEARO) as polio-free, brought the African Region closer than ever to eradication of wild poliovirus, possibly eradicated two out of three wild poliovirus strains, set the world on the path of phased Oral Polio Vaccine (OPV) removal, stopped outbreaks in Syria and Horn of Africa, and cornered wild poliovirus circulation to a joint cross-border reservoir between Afghanistan and Pakistan. — The Endgame Plan 2013-2018 “succeeded in certifying South-East Asia (SEARO) as polio-free, brought the African Region closer than ever to eradication of wild poliovirus, possibly eradicated two out of three wild poliovirus strains, set the world on the path of phased Oral Polio Vaccine (OPV) removal, stopped outbreaks in Syria and Horn of Africa, and cornered wild poliovirus circulation to a joint cross-border reservoir between Afghanistan and Pakistan.”

What if instead of just stopping oral polio vaccinations, we went ahead and switched to IPV now, before wild virus interruption?

Would that be so bad?

Well yeah, it would, since IPV doesn’t stop the transmission of the polio virus.

IPV does prevent you from actually getting paralytic polio, but not from getting a polio infection and spreading it to others. So if we switched to IPV now, we would never actually eradicate polio.

OPV, on the other hand, prevents both paralytic polio and the spread of infection. Unfortunately, it can also rarely mutate and cause paralytic polio. And when vaccination rates are low, these mutant strains can even cause outbreaks.

Why do the outbreaks of mutant strains of polio only happen when vaccination rates are low? Because in addition to preventing infection from wild strains, the polio vaccines can prevent paralytic polio that is caused by the mutant strains!

But why use a vaccine that can mutate like that? It’s simple. The risk of wild polio is so much greater before OPV gets wild polio virus strains under control.

Don’t Spoil the Polio Endgame

There have been some hiccups, but we are very close to eradicating polio.

“In 1988, when the World Health Assembly declared its commitment to eradication and the Global Polio Eradication Initiative (GPEI) was formed in pursuit of this goal, there were 350 000 annual cases of WPV in 125 countries. By the end 2018, only 33 cases were identified – all from two neighbouring countries (Afghanistan and Pakistan).”
Polio Endgame Strategy 2019–2023

And while there are plenty of challenges ahead, including:

Ongoing conflicts in the last remaining polio-affected regions.
Weak or fragile health systems and extreme poverty in both endemic and non-endemic countries.

Let’s not add to those challenges and let anti-vaccine folks bring back polio.

“The medical establishment repeatedly claims that the science regarding vaccines is settled,” said Del Bigtree, CEO and founder of Informed Consent Action Network, adding that the outbreak of vaccine-derived cases “highlights the danger of eliminating the human and civil right of informed consent with regard to vaccines — a right available for all other medical products and procedures.”
Vaccination-wary groups call for halt of oral polio vaccine

Let’s not let them scare parents away from vaccinating and protecting their kids, which would lead to even more cases of both wild polio and vaccine derived polio.

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. (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.

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.

Why Are the DPT and OPV Vaccines Still Used in Some Countries?

As most folks know, neither the DPT nor OPV vaccines are used in the United States.

Pope Francis helped launch a polio vaccine campaign when he visited Mexico in 2016.

That they are still used in other countries likely raises some questions for those folks that get them.

Why Are the DPT and OPV Vaccines Still Used in Some Countries?

As I am sure you have guessed, there is no conspiracy about the continued use of these vaccines in other parts of the world. We aren’t getting rid of old stocks of vaccines or using cheaper vaccines in poorer parts of the world.

So what’s the reason?

To understand why they are still used in other countries, it helps to understand why they aren’t used here.

Remember that the DPT vaccine, which protects folks against diphtheria, pertussis, and tetanus, came under attack in the 1970s and 80s as some folks blamed the vaccine for causing vaccine injuries, including seizures and encephalopathy. It didn’t, but we still got a new vaccine, DTaP, which doesn’t seem to work as well.

“Although concerns about possible adverse events following their administration have led to the adoption of acellular pertussis vaccines in some countries, whole-cell pertussis vaccines are still widely produced and used globally in both developed and developing countries. Whole-cell pertussis vaccines that comply with WHO requirements, administered according to an optimal schedule have a long and successful record in the control of whooping cough. Furthermore, the excellent efficacy of some currently available whole-cell pertussis vaccine has also been shown, not only in recent clinical trials, but also on the basis of the resurgence of disease where vaccination has been interrupted or when coverage has markedly decreased. Therefore, WHO continues to recommend whole-cell pertussis vaccines for use in national immunization programmes.”

WHO on Recommendations for whole-cell pertussis vaccine

The WHO now recommends that if countries do switch to DTaP, the acellular pertussis vaccine, they should be prepared to add additional periodic booster doses and immunizations during pregnancy, which may still “may not be sufficient to prevent resurgence of pertussis.”

The OPV vaccine, on the other hand, was replaced because it can rarely cause vaccine-associated paralytic polio (VAPP) and circulating vaccine-derived polio virus (cVDPV). Of course, it does it at much lower rates than wild polio virus, so until polio is well controlled, the benefit of using OPV outweighs the risk. In addition to being less expensive and easier to use, OPV has the benefit over IPV of providing better herd immunity.

At some point, as we did in the United States in 2000, countries make a switch to the IPV vaccine.

In 2016, remaining countries that use OPV switched from trivalent OPV to bivalent OPV, because wild polio virus type 2 was eradicated in 1999. Once the remaining two types are eradicated, we can stop using the OPV vaccine altogether.

Until then, countries either use:

OPV plus one dose of IPV
sequential IPV-OPV schedules – high vaccine coverage and low risk of wild polio importation
IPV only schedules – sustained high vaccine coverage and very low risk of wild polio importation

So there is no conspiracy. These vaccines are safe and they work.

Without them, there would be over:

1.3 million pertussis related deaths each year
600,000 cases of paralytic polio each year

With most of these cases affecting young children.

VAXOPEDIA

What Happens if We Stop Using Oral Polio Vaccines?