In 2012, Gregory Poland, the Editor-in-Chief of the journal Vaccine, did publish the article, The Re-Emergence of Measles in Developed Countries: Time to Develop the Next-Generation Measles Vaccines?
No where in the article does he say that the measles vaccine can’t prevent measles outbreaks.
He is just saying that since the vaccine isn’t 100% effective and because measles is so contagious, that it can’t prevent all measles outbreaks.
“Thus, measles outbreaks also occur even among highly vaccinated populations because of primary and secondary vaccine failure, which results in gradually larger pools of susceptible persons and outbreaks once measles is introduced.”
Poland et al on The Re-Emergence of Measles in Developed Countries: Time to Develop the Next-Generation Measles Vaccines?
And we likely won’t be able to eradicate measles with our current measles vaccine, “even though measles can be controlled, and even eliminated in some regions for defined periods of time.”
“Thus, while an excellent vaccine, a dilemma remains.”
Poland et al on The Re-Emergence of Measles in Developed Countries: Time to Develop the Next-Generation Measles Vaccines?
The dilemma is that measles is still around and that people who are too young to be vaccinated, too young to be fully vaccinated, and those with immune system problems who can’t be vaccinated sometimes get measles, in addition to folks who are intentionally unvaccinated.
With a better vaccine, fewer people would get caught up in outbreaks that are typically triggered by folks who are intentionally unvaccinated.
Remember, most outbreaks are traced back to someone who is unvaccinated. This is the person Dr. Poland is describing when he says “once measles is introduced,” as the endemic spread of measles has been eliminated in the United States. All cases are reintroduced from outside the country, typically when someone who is intentionally not vaccinated travels overseas and then returns with measles while they are still contagious.
“But he also said that sometimes people who oppose the vaccines will pick out one sentence in the scientific study and extrapolate it to mean things that it does not mean… He said that measles is the most contagious disease that we know, and yet we found that fear and ignorance is more so.”
Senator Carla Nelson on The Anti-vaxxers Might Wish that What was Lost had not been Found
Either way, it is important to understand something he leaves out. There are few deaths from measles these days because most folks are vaccinated!
Whatever his motivation, let’s take a look at what Dr. Bob is saying about measles…
“Measles hysteria is everywhere. And it’s clear the hysteria is a result of media fear around this disease, a disease every child used to get (and handle virtually without complication) not that long ago.”
Dr. Bob Sears
Not that long ago?
I’ve been a pediatrician for 22 years and I have never seen a child with measles. Neither did I have measles, as I was fortunate enough to grow up in the post-vaccine era for measles – a vaccine that has been available for since the 1960s.
Anti-vaccine folks try to hide the risks of measles in mortality rates, but the reality of it is that about 500 people died each year up until the early 1960s when the first measles vaccine was developed.
“There is another side to this measles conversation: how we’ve unintentionally shifted the burden of disease to babies and adults, both groups who are more likely to experience complications, by vaccinating all schoolchildren and losing natural immunity.”
After all, the MMR vaccine provides life-long immunity to most people. That’s not the problem.
If we went back to the pre-vaccine era, when everyone got measles naturally, as Dr. Bob seems to be advocating for, not only would those kids have to earn their immunity, but many babies (those who hadn’t had measles yet) and adults (those with immune system problems) would still be at great risk.
And while measles was cyclical in the pre-vaccine era, it shouldn’t be when folks are vaccinated and protected. What happened to the cycles between 1997 and 2007?
“Unlike natural immunity, the measles vaccine does NOT offer lifelong protection. Estimates of its protection average around 15 years, and describe a phenomenon in the vaccine world known as “waning immunity.”
“The other trend we’ve seen over the past 10 years is an increase in adult measles cases. “
Dr. Bob’s sidekick neglects to mention that in addition to unvaccinated kis with measles, the trend is an increase in measles cases in unvaccinated adults! After all, most folks who get measles in these outbreaks are unvaccinated.
“To recap: by losing natural immunity for measles for children 5-19 years old, we’ve exposed babies, pregnant women, and adults to measles—all vulnerable groups who are more likely to experience serious complications from the disease.”
Perhaps the only true statement that they make – “we’ve exposed babies, pregnant women, and adults to measles—all vulnerable groups who are more likely to experience serious complications from the disease.”
And no, vitamin A is not a proven therapy or measles in developed countries. It mainly helps prevent complications in kids who have a vitamin A deficiency.
As most folks know, neither the DPT nor OPV vaccines are used in the United States.
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.
No, I’m not talking about the “crude brew” that was the original DTP vaccine.
This older vaccine used more antigens than the DTaP vaccine that replaced it, so could cause more side effects. Even before that though, there was less oversight of vaccine manufacturers in the early 20th century. This could lead to vaccines that were contaminated or which simply didn’t work.
That certainly was a problem with the early smallpox vaccine, which is typically considered to be the most dangerous vaccine ever routinely used.
Variolation and Smallpox
But even before the smallpox vaccine was developed by Edward Jenner in 1796, we had variolation.
While the smallpox vaccine involved the cowpox virus, variolation actually infected someone with smallpox. The idea was to give the person a milder form by exposing them to a weaker, or attenuated, form of the virus.
They got this weakened virus from the smallpox scabs of someone who had already recovered and:
blowing dried smallpox scabs into their nose
applying pus from smallpox scabs to a small puncture wound on their skin
Variolation worked, giving the person immunity to smallpox – if they survived.
Unfortunately, about 1 to 3% of people who underwent variolation died.
And people who had recently undergone variolation could be contagious, leading to smallpox epidemics.
So why did folks undergo variolation if they had a chance of dying from the procedure?
A natural smallpox infection was so much more deadly. Up to 30% of people who got smallpox died, and many people eventually got caught up in the regular smallpox epidemics that plagued people in the pre-vaccine era.
The Hospital Rock Engravings of Farmington, Connecticut
We don’t have to worry about smallpox anymore.
Well, not about natural smallpox infections, since smallpox was eradicated back in 1980.
And there are many other diseases that we get vaccinated against, with it being extremely easy to get that protection, especially compared to what folks did in the old days.
Do you know how far folks went to make variolation safer?
“Every year, thousands undergo this operation, and the French Ambassador says pleasantly, that they take the small-pox here by way of diversion, as they take the waters in other countries. There is no example of any one that has died in it, and you may believe I am well satisfied of the safety of this experiment, since I intend to try it on my dear little son. I am patriot enough to take the pains to bring this useful invention into fashion in England…”
Lady Mary Wortley Montagu On Small Pox in Turkey (1717)
They actually went to smallpox hospitals to get vaccinated, remaining in quarantine for up to three weeks so that they wouldn’t get others sick.
In Farmington, Connecticut, two doctors established the Todd-Wadsworth Smallpox Hospital and had a lot of success with variolation.
Patients were no longer starved before inoculation, and many had begun to doubt the efficacy and safety of vomiting, sweats, purges, mercurials (toxic mercury salts such as calomel), and bleeding which had previously weakened both inoculees and those who “took the pox in the natural way.”
Charles Leach, MD on Hospital Rock
There, up to 20 patients at a time stayed in quarantine to get variolated, as a smallpox epidemic hit nearby Boston.
Between 1792 and 1794, many who got variolated wrote their names on what is now known as Hospital Rock.
“Many have supposed that the names on this rock were those who had did of the small-pox, but this is a great mistake. Every name on the rock is that of a person who was living when the name was placed there. Norris Stanley lived to own ships which were captured in the war of 1812 by Algerian pirates and still later to receive from the United States an indeminity therefor amounting to a large sum.”
James Shepard on The Small Pox Hospital Rock
The nearby town of Durham seemed to go a different way.
Instead of an inoculation hospital, they had a pest house to quarantine folks with natural smallpox infections.
Adding to the history of smallpox in Connecticut – a smallpox burying ground in Guilford.
Why wasn’t variolation popular everywhere? Folks didn’t have to wait for the first vaccine for the anti-vaccine movement to get started.
What to Know About Smallpox and the Hospital Rock Engravings
Hundreds of people got safely inoculated against smallpox and left their names on Hospital Rock near Farmington, Connecticut just before Edward Jenner discovered the first smallpox vaccine.
We often have to remind people that the anti-vaccine movement didn’t start with Bob Sears, or Jenny McCarthy, or even with Andy Wakefield.
Did you know that the Reverend Cotton Mather’s house was bombed in Boston in 1721? Well, someone through a bomb through his window. Fortunately, it didn’t go off.
That’s 77 years before Jenner developed his smallpox vaccine!
What was Mather doing?
He had started a smallpox variolation program. He was trying to protect people in Boston from smallpox during one of the most deadly epidemics of the time.
So essentially, the anti-vaccine movement started before we even had real vaccines…
Is the Anti-Vaccine Movement Growing?
You see reports of more and more outbreaks of vaccine-preventable diseases, hear about new vaccine laws and mandates, and depending on who your friends are, may see a lot of anti-vaccine articles and vaccine injury stories getting shared on Facebook.
You have probably even heard about pediatricians firing families who refuse to vaccinate their kids.
So what’s the story?
Is the anti-vaccine movement growing?
Is there a growing resistance among parents to getting their kids vaccinated?
“Parents are taking back the truth. It is my expectation that this crack in the dam will serve to sound an alarm. To wake women up. To show them that they have relinquished their maternal wisdom, and that it is time to wrest it back.”
Kelly Brogan, MD
Is the world finally “waking up to the dangers of vaccines,” like many anti-vaccine experts have been claiming for years and years?
The Anti-Vaccine Movement is not Growing
Many people will likely tell you that the anti-vaccine is in fact growing.
You can read it in their headlines:
The worrying rise of the anti-vaccination movement
Will 2017 be the year the anti-vaccination movement goes mainstream?
Pediatricians calling anti-vaccine movement a growing problem
There’s Good Evidence That The Anti-Vaccine Movement Is Growing
I was skeptical that the anti-vaccine movement was gaining traction. Not anymore.
But the anti-vaccine movement is not necessarily growing.
The overwhelming majority of parents and adults are fully vaccinated.
Most parents do their research though, don’t jump on the anti-vaccine bandwagon, and know that vaccines work, vaccines are safe, and vaccines are necessary.
The Anti-Vaccine Movement is Changing
A lot about the anti-vaccine movement hasn’t changed over the last 100 plus years.
Many early critics of vaccines were alternative medicine providers, including homeopaths and chiropractors, just like we see today. And like they do today, they argued that vaccines didn’t work, vaccines were dangerous, and that vaccines weren’t even necessary.
The big difference?
Unlike when Lora Little, at the end of the 19th century, had to travel around the country to distribute her anti-vaccine pamphlet, Crimes of the Cowpox Ring, anti-vaccine folks can now just tweet or post messages on Facebook. It is also relatively easy to self-publish an anti-vaccine book and sell it on Amazon, put up your own anti-vaccine website, post videos on YouTube, or even make movies.
“Whatever you think about Andrew Wakefield, the real villains of the MMR scandal are the media.”
Ben Goldacre on The MMR story that wasn’t
Fortunately, all of that is balanced by something they don’t have anymore.
No, it’s not science. That was never on their side.
It’s that the media has caught on to the damage they were doing and isn’t as likely to push vaccine scare stories anymore.
Explaining the Popularity of the Anti-Vaccine Movement
The anti-vaccine movement has always been around and they are likely not going anywhere, whether or not they are growing.
“By the 1930s… with the improvements in medical practice and the popular acceptance of the state and federal governments’ role in public health, the anti-vaccinationists slowly faded from view, and the movement collapsed.”
Martin Kaufman The American Anti-Vaccinations and Their Arguments
Why so many ups and downs?
It is easily explained once you understand the evolution of our immunization programs, which generally occurs in five stages:
pre-vaccine era or stage
increasing coverage stage – as more and more people get vaccinated and protected, you pass a crossover point, where people begin to forget just how bad the diseases really were, and you start to hear stories about “mild measles” and about how polio wasn’t that bad (it usually wasn’t if you didn’t get paralytic polio…)
loss of confidence stage – although vaccine side effects are about the same as they always were, they become a much bigger focus because you don’t see any of the mortality or morbidity from the diseases the vaccines are preventing. It is at this point that the anti-vaccine movement is able to be the most effective.
resumption of confidence stage – after the loss of confidence in stage three leads to a drop in vaccine coverage and more outbreaks of a vaccine-preventable disease, not surprisingly, more people understand that vaccines are in fact necessary and they get vaccinated again. It is at this point that the anti-vaccine movement is the least effective, as we saw after outbreaks of pertussis in the UK in the 1970s and measles more recently. You also see it when there is a report of an outbreak of meningococcal disease on a college campus or a child dying of the flu on the local news, etc.
eradication stage – until we get here, like we did when smallpox was eradicated, the anti-vaccine movement is able to cycle through stages two to four, with ups and downs in their popularity,
So the anti-vaccine movement is able to grow when they have the easiest time convincing you that the risks of vaccines (which are very small) are worse than the risks of the diseases they prevent (which are only small now, in most cases, because we vaccinate to keep these diseases away, but were life-threatening in the pre-vaccine era).
“As vaccine use increases and the incidence of vaccine-preventable diseases is reduced, vaccine-related adverse events become more prominent in vaccination decisions. Even unfounded safety concerns can lead to decreased vaccine acceptance and resurgence of vaccine-preventable diseases, as occurred in the 1970s and 1980s as a public reaction to allegations that the whole-cell pertussis vaccine caused encephalopathy and brain damage. Recent outbreaks of measles, mumps, and pertussis in the United States are important reminders of how immunization delays and refusals can result in resurgences of vaccine-preventable diseases.”
Paul Offit, MD on Vaccine Safety
Fortunately, most parents don’t buy into the propaganda of the anti-vaccine movement and don’t wait for an outbreak to get their kids vaccinated and protected. They understand that you can wait too long.
The bottom line – except for pockets of susceptibles and clusters of unvaccinated kids and adults, most people are vaccinated. If the anti-vaccine does grow, it eventually gets pulled back as more kids get sick.
What to Know about the Growing Anti-Vaccine Movement
Although they may have an easier time reaching more people on Twitter, Facebook, YouTube, and with Amazon, the overwhelming majority of parents vaccinate their kids and aren’t influenced by what some people think is a growing anti-vaccine movement.
Polio is one of the most well known causes of acute flaccid paralysis.
Although most people with polio infections have no symptoms at all, or just have a very mild illness, with a sore throat and a low grade fever, a small percentage can develop:
a loss of superficial reflexes
severe muscle aches and spasms in their limbs or back
an asymmetrical flaccid paralysis with diminished deep tendon reflexes
This acute flaccid paralysis only affects the child’s strength in the affected muscle groups – there is no loss of sensation. The severity of the symptoms and the disease depends on which muscles are affected the most. If it is just your legs, then you will have trouble walking. On the other hand, if it affects your chest, then you might not be able to breath, unless you are put on a ventilator (iron lung).
Acute Flaccid Paralysis
Thinking about it in the context of polio, it becomes easy to understand acute flaccid paralysis or AFP.
It is the sudden onset (acute) of a flaccid (floppy or poor muscle tone) paralysis (weakness or inability to move) of one or more muscles.
But what many people don’t understand, is that in addition to polio, there are many more non-polio causes of AFP.
Many of us got a crash course in non-polio acute flaccid paralysis (NP-AFP) a few years ago when we started hearing reports of kids developing polio-like paralysis in 2014. Now thought to be caused by enterovirus D68 infections (EV-D68), the paralysis followed respiratory tract infections in many of the affected children. All together, at least 120 children in 34 states developed acute flaccid paralysis that year.
Interestingly, EV-D68 is one of more than 100 non-polio enteroviruses. The virus that causes hand, foot, and mouth disease, coxsackievirus A16, is another. Others cause pinkeye, meningitis, or encephalitis.
Keep in mind that many other viruses and conditions can cause non-polio AFP too, including:
other infections, including novel enterovirus C105, a non-polio enterovirus, and even tick-borne (Lyme disease) and mosquito-borne (Japanese encephalitis) infections
How do you determine the cause and how do you know it isn’t polio?
These kids with AFP typically have extensive testing to determine what is causing their AFP, including an MRI, antibody tests, and testing of their cerebrospinal fluid, etc. Although it isn’t always possible to identify a cause, you can at least rule out many potential suspects, like trauma, polio, and other infections.
Myths About Polio and Acute Flaccid Paralysis
Some folks don’t believe in non-polio AFP.
They believe that polio never really disappeared because vaccines don’t really work and that polio was simply renamed to, you guessed it, acute flaccid paralysis.
“Unbeknownst to most doctors, the polio-vaccine history involves a massive public health service makeover during an era when a live, deadly strain of poliovirus infected the Salk polio vaccines, and paralyzed hundreds of children and their contacts. These were the vaccines that were supposedly responsible for the decline in polio from 1955 to 1961! But there is a more sinister reason for the “decline” in polio during those years; in 1955, a very creative re-definition of poliovirus infections was invented, to “cover” the fact that many cases of ”polio” paralysis had no poliovirus in their systems at all. While this protected the reputation of the Salk vaccine, it muddied the waters of history in a big way.”
Suzanne Humphries, MD on Smoke, Mirrors, and the “Disappearance” Of Polio
What’s their evidence?
A rise in cases of non-polio AFP in India since 1997.
How do we know that there has been a rise in non-polio AFP cases in India since 1997?
It’s very simple and explains why there isn’t any data on before that 1997.
As part of the strategy to eliminate polio in that country, starting in 1997, all cases of AFP started getting tested for polio. It was a way to track the effectiveness of the immunization program. If you were seeing too many cases of AFP caused by polio, then not enough people were getting vaccinated. On the other hand, if you weren’t seeing any cases of AFP in an area, then the testing and surveillance probably wasn’t getting none, since there will always be some cases of non-polio AFP.
Unfortunately, they found many cases to track. And the cases kept increasing, although more and more, they weren’t being caused by polio. At least not by live polio virus.
Were they caused by the polio vaccine?
In some cases, yes. It is well known that the live polio vaccine can rarely cause VAPP and cVDPV.
By 2015, after India was declared free of polio (the last case was in 2011), none of those cases of AFP were found to be caused by wild polio though. And India hasn’t had a case of cVDPV since 2010.
Why the increase in cases of non-polio AFP? It certainly isn’t because of Suzanne Humphries’ polio virus renaming conspiracy or any other anti-vaccine conspiracy involving the polio vaccine itself.
If we simply renamed polio to non-polio AFP, why did the numbers drop for so long and then slowly start to increase? Shouldn’t it have been a rapid crossover?
More importantly, why are the case of paralysis from non-polio AFP so much lower than the pre-vaccine era cases of AFP from polio?
And how come we rarely see large outbreaks of AFP like we did in the pre-vaccine era?
Sure, 120 kids in the EV-D68 non-polio AFP outbreak of 2014 is way more than any of us would like to see, but it is tremendously less than what we used to see in the pre-vaccine era from polio.
“Poliomyelitis is one of the important emergent viral diseases of the twentieth century… At its height, from 1950–1954, poliomyelitis resulted in the paralysis of some 22,000 U.S. citizens each year… Many thousands were left permanently disabled by the disease, while many others suffocated as a consequence of respiratory paralysis.”
Barry Trevelyan on the The Spatial Dynamics of Poliomyelitis in the US
While anti-vaccine conspiracy theories about AFP are as easy to dismiss as all of the rest they bring up, what is behind the rise in AFP in some areas of the world?
Although one study that was published in Pediatrics, “Trends in Nonpolio Acute Flaccid Paralysis Incidence in India 2000 to 2013,” did find a correlation between the use of the OPV vaccine and the incidence of non-polio AFP, many experts think the rise is a result of better screening. Also, once polio gets under control, other more neglected diseases start getting more attention, like enteroviral infections. Not surprisingly, other parts of the world have had the same experience.
There is also the fact that in 2005, the Global Poliomyelitis Eradication Initiative began “to cast a wider net for poliovirus detection and to maximize sensitivity so that every poliomyelitis case is detected.” Why? If even a single case was missed, it could lead to continued outbreaks and would get in the way of polio elimination in the country.
“This large increase in NP-AFP cases, which represent AFP cases caused by agents other than poliovirus, probably reflects the excellent implementation of the expanded definition of AFP and highly sensitive surveillance and detection methods used by NPSP in India from 2005 onwards…”
C. Durga Rao on Nonpolio Acute Flaccid Paralysis in India
So did the polio vaccine recently cause 53,000 paralysis victims in India?
The polio vaccine has worked to get us on the brink of eradicating polio though.
What To Know About Acute Flaccid Paralysis
Acute flaccid paralysis can be caused by the polio virus, but non-polio acute flaccid paralysis becomes a more important cause once polio is eliminated in a region.
Circulating vaccine-derived polio virus or cVDPV are outbreaks of polio that are actually caused by the polio vaccine.
Very rarely, the attenuated (weakened) virus in the oral polio vaccine can revert to a form that can cause the person who was vaccinated or their close contact to actually develop polio.
It should not be confused with VAPP or vaccine-associated paralytic polio. With VAPP, the original strain of attenuated vaccine virus reverts to a form that can cause polio, but it does spread from one person to another, so does not lead to outbreaks.
Fortunately, both VAPP and cVDPV are rare.
How rare? VAPP only occurs in about 1 in every 1.27 million children receiving their first dose of OPV.
And according to the WHO, there had only been about 24 outbreaks of cVDPV over the past 10 years. Tragically, this has resulted in at least 750 cases of paralytic polio in 21 countries.
A new outbreak of cVDPV in Syria adds to those numbers though.
After being polio free for 15 years, since 1999, Syria began having cases of wild type polio again in 2013 (35 cases) and 2014 (1 case). Those polio cases and the emergence of an outbreak of cVDPV2 (there are three strains of polio virus – this outbreak was caused by the type-2 strain) highlight the effects of years of poor immunization rates because of war.
While there are many challenges to getting kids vaccinated in Syria, up to 355 vaccination teams with 61 supervisors will be working out of five vaccine distribution centers to vaccinate 328,000 children to control the outbreak and get kids vaccinated.
Circulating Vaccine-Derived Polio Virus
Just like wild type polio, we can stop cVDPV by increasing vaccination rates and increasing access to improved sanitation facilities.
Although anti-vaccine folks routinely cry wolf about shedding, the oral polio vaccine really does shed – in the stool of people who have been recently vaccinated. You can then be exposed to the attenuated polio vaccine virus (which can help give immunity to others in the community by passive immunization) or a strain of cVDPV (which can, unfortunately, help give others, especially if they are not vaccinated, paralytic polio) if they are exposed to open sewage or can not practice proper hygiene, etc.
Can’t we just stop using the live, oral polio vaccine?
Although a serious side effect of the vaccine, the vaccine’s benefits clearly outweigh the risk of both VAPP and cVDPV while polio is endemic (lots of cases) in a region, after all, without the vaccine, hundreds of thousands of children would get polio and would be paralyzed.
In polio-free countries, the risks of VAPP and cVDPV becomes greater than the risk of polio though, and they move to the inactivated polio vaccine. That helps prevent a situation in which the polio vaccines actually causes more cases of polio than wild type polio viruses.
Eventually, all countries will move to the IPV vaccine as we move closer to polio eradication. We came one step closer to that point in April 2016 when all countries that were still using the oral polio vaccine switched from trivalent OPV (three strains) to bivalent OPV (two strains) for their routine immunization programs. This could eliminate up to 90% of cases of cVDPV (most are caused by the type-2 strain which is not in bOPV)!
What To Know About cVDPV
Circulating vaccine-derived polio virus outbreaks are a rare side effect of the oral polio vaccine.