Vaccine-Derived Polio Is On the Rise (npr.org) 83
An anonymous reader quotes a report from NPR: Is polio making a comeback? The world has spent billions of dollars over the last 15 years in an effort to wipe out the virus through vaccination efforts -- with encouraging results. Rates plunged from an estimated 350,000 cases in 1988 to just several dozen by 2016. But in recent years, polio incidence has started to inch back up. The reason has to do with the type of vaccine used in many parts of the world, primarily in low- and middle-income countries. While the United States and other Western countries inject an inactivated virus that poses no risk of spread and are now polio-free, other countries rely on an oral vaccine. It's cheap, it's easy to administer and two or more doses confer lifelong immunity. But it's made with living, weakened virus. And that poses a problem.
Those who've been immunized with live virus can shed it in their stool, which can then spread through sewage in places with poor sanitation. If the virus stays weak, it can even expose the unvaccinated to polio and give them immunity. But if it mutates and regains virulence, someone who isn't vaccinated can become sick with vaccine-derived polio after contact with the contaminated wastewater. And now countries that had previously eradicated polio in Africa, the Middle East and parts of Asia are seeing new outbreaks of vaccine-derived polio.
One reason for this rise in cases, say polio experts, is that gaps in immunization in recent years have created more opportunities for the unvaccinated to become infected. "Vaccination campaigns have been certainly affected by the pandemic," says Raul Andino, a virologist at University of California, San Francisco. [...] The composition of the oral vaccine has also been a factor. In 2016, eyeing an uptick in vaccine-derived polio, global health officials altered the composition of the oral vaccine. Previously, the vaccine protected against all three types of wild polio -- the virus that circulates naturally in the environment. Then they withdrew one of those types -- the one that was leading to most of the vaccine-derived cases but whose wild form had been successfully eradicated. Only there was a development that hadn't been anticipated. Vaccine-derived poliovirus of that type was still in circulation from earlier iterations of the oral vaccine -- and now with the reformulated vaccine, increasing numbers of people who were no longer vaccinated against it. So there was further spread. Thankfully, a new kind of vaccine being rolled out is showing promise. "The novel vaccine still contains a weakened version of the virus, but it's been hobbled even further," reports NPR.
"The researchers tweaked the virus so that it has to accumulate more mutations to become virulent and has a harder time amassing those mutations. For example, they've altered the polymerase, one of the key enzymes responsible for introducing mutations, reducing its ability to mix and match genes from different viruses."
Those who've been immunized with live virus can shed it in their stool, which can then spread through sewage in places with poor sanitation. If the virus stays weak, it can even expose the unvaccinated to polio and give them immunity. But if it mutates and regains virulence, someone who isn't vaccinated can become sick with vaccine-derived polio after contact with the contaminated wastewater. And now countries that had previously eradicated polio in Africa, the Middle East and parts of Asia are seeing new outbreaks of vaccine-derived polio.
One reason for this rise in cases, say polio experts, is that gaps in immunization in recent years have created more opportunities for the unvaccinated to become infected. "Vaccination campaigns have been certainly affected by the pandemic," says Raul Andino, a virologist at University of California, San Francisco. [...] The composition of the oral vaccine has also been a factor. In 2016, eyeing an uptick in vaccine-derived polio, global health officials altered the composition of the oral vaccine. Previously, the vaccine protected against all three types of wild polio -- the virus that circulates naturally in the environment. Then they withdrew one of those types -- the one that was leading to most of the vaccine-derived cases but whose wild form had been successfully eradicated. Only there was a development that hadn't been anticipated. Vaccine-derived poliovirus of that type was still in circulation from earlier iterations of the oral vaccine -- and now with the reformulated vaccine, increasing numbers of people who were no longer vaccinated against it. So there was further spread. Thankfully, a new kind of vaccine being rolled out is showing promise. "The novel vaccine still contains a weakened version of the virus, but it's been hobbled even further," reports NPR.
"The researchers tweaked the virus so that it has to accumulate more mutations to become virulent and has a harder time amassing those mutations. For example, they've altered the polymerase, one of the key enzymes responsible for introducing mutations, reducing its ability to mix and match genes from different viruses."
Vaccination applies selective pressure (Score:1)
Anything will evolve under selective pressure, and things that reproduce rapidly will evolve more rapidly.
Selective pressure that presents a very steep gradient to survival is less likely to leave a path for continued survival via mutation and evolution, but selective pressure that is weaker will leave more paths for eventual resurgence.
Film at 11.
Re:Vaccination applies selective pressure (Score:5, Informative)
Re: Vaccination applies selective pressure (Score:3, Insightful)
If the "weakened" virus survives in the wild, then it's got some fitness to exist and reproduce outside of the original conditions pre vaccine.
No it's not a one-to-one analogy with antibiotic resistance but Darwinian selection occurs with anything that reproduces itself.
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If the "weakened" virus survives in the wild, then it's got some fitness to exist and reproduce outside of the original conditions pre vaccine.
That's the definition of a weakened virus. If it can't infect cells, it can't create immunity. One of the big reasons for using OPV is the assumption that a certain percentage of people are more likely to be orally exposed to human waste through poor water quality, and that not all of them will get vaccinated, and that by using the oral poliovirus vaccine, there's a good chance that they'll get infected by the almost harmless weakened virus before they get exposed to the wild poliovirus at some point in t
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The only ways to fix this are A. by improving sanitation, B. by giving anyone who hasn't gotten OPV and trivalent IPV, or C. by finding a way to create a trivalent IPV in which the type 2 strain is weakened even further, and repeating that process until the last traces of vaccine-derived type 2 poliovirus are gone. Right now, they're choosing C., because it is likely to be the simplest and cheapest of the three approaches.
Actually, I'm not even sure that's a necessary approach. I don't think OPV is even still in use anymore, so presumably if they just gave IPV shots to the people who got the bivalent OPV between 2016 and 2019, the problem would be solved.
Re: Vaccination applies selective pressured (Score:1)
It's Evolution and Vaccination (Score:5, Insightful)
Polio is coming back because people are not being vaccinated against a particular strain. This is not evolution. It's lack of vaccination.
It's both. The strain they are not being vaccinated against is one of the weakened strains used in an older version of the vaccine. This strain has evolved to become virulent again and is now infecting people who have taken the newer vaccination which no longer protects against it. This is why live virus vaccinations are risky because the weakened viruses they use can evolve to become nasty again.
Re: It's Evolution and Vaccination (Score:1)
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if it mutates and regains virulence
Missing the details. (Score:2)
Not even the article, but the tiny synopsis states otherwise:
if it mutates and regains virulence
Yes, the synopsis speaks about mutation.
More precisely baseline mutation that happen constantly and there is a tiny risk that it reverts the mutation that made it attenuated in the first place.
It doesn't speak about mutation leading to immunity escape.
Whereas the parent poster was speculating about the antibodies in the general population being a selective pressure that would push a virus to escape immunity
Which isn't the case here.
(In fact it's the opposite: the population in some poor and mid-income count
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because people are not being vaccinated against a particular strain. This is not evolution.
Wait, what? That strain spreading relative to other strains is natural selection, which is very much a part of evolution.
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because people are not being vaccinated against a particular strain. This is not evolution.
Wait, what? That strain spreading relative to other strains is natural selection, which is very much a part of evolution.
If we eradicate COVID-19, but influenza continues to spread relatively quickly by comparison, is influenza evolving to avoid the COVID vaccine? No. Nor is type 2 vaccine-derived poliovirus evolving to evade the type 1 or type 3 poliovirus vaccines. Natural selection does not apply here.
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From the summary:
It is not coming back because people are not being vaccinated. It is coming back because people are being vaccinated by live strains.
Ahem. From TFS:
"While the United States and other Western countries inject an inactivated virus that poses no risk of spread and are now polio-free..."
The actual reason for this coming back, is the same as always; Greed.
Why is it after half a damn century and billions spent, we're still forcing anywhere on the planet to use a live vaccine when we have proven risk-free alternatives? I kind of doubt a vaccine-derived phenomenon like this, is limited to polio. I wonder what's next.
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The original reason for using weakened live vaccines is to increase the number of people exposed, as the weakened virus can spread from the vaccinated to the unvaccinated, hopefully enough to create a herd immunity.
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The actual reason for this coming back, is the same as always; Greed.
Ah, we all long to live in a simple world, where every question or conflict has a simple black and white moral answer.
But it is not just a question of cost that you might imagine while in full SJW mode.
The Oral Polio Vaccine has other advantages over the IPV, especially in a country where polio is still spreading.
https://polioeradication.org/p... [polioeradication.org]
https://www.who.int/teams/heal... [who.int]
Virtually all countries which have eradicated polio used OPV to interrupt person to person transmission of the virus.
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The part where it says it was used because it was cheap is, in fact, not entirely truthful. It is cheaper, but that's not the only reason that it was still used in a lot of countries.
Oral poliovirus (OPV) vaccines are also more effective at producing mucosal immunity than IPV because of the method of administration (oral versus shot). In areas where polio is actively spreading, that mucosal immunity results in much better protection against infection than IPV provides.
Additionally, OPV can be administere
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Why is it after half a damn century and billions spent, we're still forcing anywhere on the planet to use a live vaccine when we have proven risk-free alternatives? I kind of doubt a vaccine-derived phenomenon like this, is limited to polio. I wonder what's next.
I'm having a hard time finding a single article explaining it, but the Oral vaccine and the Inactivated Vaccine are used for different purposes. I think OPV is easier to distribute, and I think it is effective against all 3 strains of polio. So in a population where Polio is circulating, you give them OPV. As the nation develops herd immunity and Polio spread goes down, they can switch to IPV which puts the nation in more of a "maintenance mode." But only if they have the infrastructure to give 4 shots
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There's a WHO video that does a really good job of explaining it.
https://www.youtube.com/watch?... [youtube.com]
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I'm having a hard time finding a single article explaining it, but the Oral vaccine and the Inactivated Vaccine are used for different purposes. I think OPV is easier to distribute, and I think it is effective against all 3 strains of polio. So in a population where Polio is circulating, you give them OPV. As the nation develops herd immunity and Polio spread goes down, they can switch to IPV which puts the nation in more of a "maintenance mode." But only if they have the infrastructure to give 4 shots on a schedule.
Mostly. Some caveats, though:
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Sort of. They actually quit using that particular strain in the weakened virus vaccines because it had been eradicated from the wild. That particular weakened strain of the virus used in the vaccine evolved and spread on it's own. If enough people are vaccinated for it, it will not be able to spread on it's own.
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Those who've been immunized with live virus can shed it in their stool, which can then spread through sewage in places with poor sanitation. If the virus stays weak, it can even expose the unvaccinated to polio and give them immunity. But if it mutates and regains virulence, someone who isn't vaccinated can be
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It's 100% correct. People vaccinated by the live strain can she the virus in their stool which spreads in sewage and can infect other people. If they used the non-live virus this would not happen.
Instead, some nontrivial number of individuals who were accidentally vaccinated through contaminated water would have eventually gotten infected by the wild poliovirus, which is likely to be even more severe. So it was still the right call, I suspect.
If there was a mistake, it was the decision to transition from trivalent OPV to bivalent OPV rather than transitioning from OPV to IPV. That said, I think there was only about a three-year period between when the bivalent OPV became available (2016) and when
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Sort of. They actually quit using that particular strain in the weakened virus vaccines because it had been eradicated from the wild. That particular weakened strain of the virus used in the vaccine evolved and spread on it's own. If enough people are vaccinated for it, it will not be able to spread on it's own.
It's not that the virus evolved and spread on its own. Spreading on its own was always part of the vaccine's design, to ensure that people exposed to feces in their drinking water would have at least some chance of being accidentally vaccinated, rather than accidentally infected by the non-attenuated virus.
The evolution was that it combined with the type 1 attenuated virus, and the result is less attenuated (causes more serious illness).
And the problem that caused the resurgence is that there's still too m
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That's the problem. Had vaccines been used with the "inactive" virus, this would not have been a problem. But you know money got in the way..
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That's the problem. Had vaccines been used with the "inactive" virus, this would not have been a problem. But you know money got in the way..
But how many more people would have died if they had tried to use IPV? It's not just money. It's also infrastructure and time and the infeasibility of getting 100% coverage:
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Couldn’t even make it halfway into the first paragraph I see.
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Anything will evolve under selective pressure, and things that reproduce rapidly will evolve more rapidly.
Literally not even remotely how evolution works, but thanks for trying.
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Well at least not the way you phrased it.
It's got to do with evolution, sure. Because thins that get to "reproduce" get a chance to mutate and thus evolve. It's an inherent risk for this particular type of vaccination.
But it has nothing to do with selective pressure or other types of vaccines that don't use viruses that are able to "reproduce".
'Live' viruses mutate. Film at 11 -- would have been more appropriate.
Your title is wrong. Vaccination fights evolution. (Score:3)
Your title Vaccination applies selective pressure is wrong.
Anything will evolve under selective pressure,
This can be true under some circumstances (e.g.: if the pressure is gentle enough, and the anything has a reproduction and mutation rate high enough to explore the possibilities before the pressure has definitely extinguished it), but not always true.
and things that reproduce rapidly will evolve more rapidly
This is where the "vaccine cause evolution" breaks down.
At the individual scale, the whole point of vaccines (that target microbes) is to train your immune system in advance, so it has a specific adapti
Vaccination does not apply selective pressure. (Score:1)
Gaps in immunization (Score:2, Interesting)
... gaps in immunization in recent years ...
Take a guess why there gaps are happening in recent years?
Have it something to do with the anti-vax misinformation coming from a certain country with great influence in the world?
Or was it thanks to one particular country using vaccination program as a cover to secretly collect DNA samples to locate a certain person to have him killed, creating a huge distrust in vaccination programs in general?
Re:Gaps in immunization (Score:4, Insightful)
The Taliban were fighting vaccination for a long time, well before bin Laden's capture. Now that fight has infected American Christians. Funny how certain viruses reproduce, eh?
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The best part of the religious wars is that The Bible and the Koran are the basically same book but one uses "Allah" instead "God".
Jesus, Mary, Moses, Abraham... they're all in there. How many Christians even know that?
https://en.wikipedia.org/wiki/... [wikipedia.org]
The main difference is that in the Koran it says the crucifixion was faked by the Romans to fool the people who wanted Jesus dead, ie. no resurrection was necessary.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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The best part of the religious wars is that The Bible and the Koran are the basically same book but one uses "Allah" instead "God".
Er, not really. Allah is just the Arabic word for God, so is used in the Arabic translation of the Bible also. It pre-dates Islam.
Neither of them are proper nouns like "Jehovah". The muslim god, like the christian god, is nameless. This may stem from the Jewish taboo of saying the God's name.
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So... one book uses "Allah", the other uses "God". Got it.
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So... one book uses "Allah", the other uses "God". Got it.
Nope. Totally missed it. "God" is used in English translations of both books.
You do realise the bible was not written in English, right? Not even Olde English.
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If I knew, or cared, more about Mormonism, I might add that to the list - with the most recent prophet being that Joe Smith con-man with the amazing golden plates that nobody has ever seen. Lots of smaller sects fall into the same bucket.
And yes, that does mean that Mo, Jeebus, and the whole pantheon of Jewish prophets were con-men too. No less so than L.Ron Hubbard.
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The Taliban were fighting vaccination for a long time, but you surely can't think actualizing their propoganda [wired.com] didn't make things much worse
The Taliban were right block immunization (Score:2)
AFAIK it was not a general immunization program at all, but only a vaccination program against Polio. It was obvious that the goal had nothing to do with caring for Afghan children's health, but rather to try to make Polio extinct globally so that we could stop taking the vaccine in west. Pure self interest.
That pissed them off. And then they found that the CIA was using the vaccination program to gather intelligence.
Polio is a rich man's problem. Most people only get very mild symptoms, a small percen
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So their is a benefit to the west. But their is also a benefit to the children of Afghanistan. If both groups benefit it cannot be pure self interest.
Yes the CIA should never have used the program for intelligence gathering.
So rather then trying to eliminate a problem that they have a solution for they should just ignore it?
$5 ($1 for the vaccine and $4 for distribution) * 140 million(births a year) = $900 million dollars/year.
$900 million is not a lot to put towards solutions for other problems but can im
Re: Gaps in immunization (Score:2, Interesting)
Or perhaps misinformation about the efficacy of vaccines and lockdowns and deadliness of diseases coming straight from the establishment. Less people trust the CDC and WHO now than they did before, because they blew their trust on political games with dictators.
Good luck with your nearly infinite whack-a-mole (Score:2)
You going make a vaccine for *hundreds of millions* of viruses?
https://science.slashdot.org/s... [slashdot.org]
FTA:
To make sure others can take advantage of the work, Babaian’s team has created a public repository of the tools it developed, along with the results. The amount of cloud-based, publicly available DNA sequences is expanding exponentially; if he did the same analysis next year, Babaian says he would expect to find hundreds of thousands more RNA viruses. “By the end of decade, I want to identify over
Another reminder that health... (Score:2, Insightful)
Re:Another reminder that health... (Score:5, Insightful)
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Meanwhile you're probably a European that has depended on the US to defend you for the last 70 years. It's probably quite true that the reason your country didnt fall behind the Iron Curtain was because of the US. The EU's total GDP is 2 trillion dollars greater than the United State's and has 100 million more people https://www.worldometers.info/... [worldometers.info] and they couldnt even defend themselves against Russia on their own if this war in Ukraine got out of hand. That's pretty pathetic.
The US certainly isnt perfec
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Hahaha, what a troll you are. I specifically stated at the end of my post that my own country was certainly not perfect and here you are creating false narratives about me. Why not call me a racist too while you're just wildly making things up about me?
I'm just trying to smack you out of it for a second so you get that one horrifying glimpse of the fact that what you think is true...
After that you're going on to claim your trolling has noble aims? I really did laugh out loud for a moment when I read that. What a truly small and miserable person I must be talking to.
And by the way, I'm not going to make up bullshit claims of enlightenment
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Hahaha, keep trying to crawl up onto that higher ground troll.
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Oh please, if people have their faith in vaccines shaken by that then they either want to have their faith in vaccines shaken or they're so ignorant/uneducated that they'll believe anything.
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Were they actually giving out vaccines? If they were then the program wasn’t fake.
Re: Another reminder that health... (Score:2)
How's SV40 doing? (Score:4, Interesting)
from sv40.org-
SV40 was the 40th virus found in rhesus monkey kidney cells when these cells were used to make the polio vaccine. This virus contaminated both the Inactivated Polio Vaccine (IPV) created by Dr. Jonas Salk and the Oral or "Live" Polio Vaccine (OPV) created by Dr. Albert Sabin.
Children being fed sugar cubes with the oral polio vaccine. Circa 1961.
In 1961, SV40 was discovered by Dr. Bernice Eddy of the National Institute of Health, Division of Biologics when she took the material used to grow polio vaccines and injected it into hamsters. Tumors grew in the hamsters. Her discovery was subsequently validated by Drs. Maurice Hilliman and Benjamin Sweet of Merck.
Upon the discovery that SV40 was an animal carcinogen that had found its way into the polio vaccines, a new federal law was passed in 1961 that required that no vaccines contain this virus. However, this law did not require that SV40 contaminated vaccines be thrown away or that the contaminated seed material (used to make all polio vaccines for the next four decades) be discarded. As a result, known SV40 contaminated vaccines were injected into children up until 1963. In addition, it has been alleged that there have been SV40-contaminated batches of oral polio vaccine administered to some children until the end of the 1990's.
The Creation of the Oral Polio Vaccine
Type I has the following lineage:
In 1941, Drs. Francis and Mack isolated the Mahoney poliovirus “from the pooled feces of three healthy children in Cleveland.” Dr. Salk then subjected the strain to passages through fourteen living monkeys and two cultures of monkey testicular cultures.
In 1954, the strain (now called Monk14 T2) was given to Drs. Li and Schaeffer who subjected the virus to nine more passages through monkey testicular cultures.
Next, the strain (now called Monk14 T11) underwent fifteen more passages in monkey testicular cultures, eighteen passages in monkey kidney cells, two passages through the skin of living rhesus monkeys, and additional passages through African Green monkey skin and monkey kidney cell cultures. This strain was now called MS10 T43 or LS-c.
In 1956, Dr. Sabin took this virus and passaged it through seven cultures of African Green Monkey kidney cells.
That same year, the pharmaceutical company, Merck, Sharp & Dohme, passed the strain (now called LS-c, 2ab/KP2) through a rhesus monkey kidney cell culture.
The resulting material was called Sabin Original Merck (SOM) and was provided to Lederle in 1960 as the seed material to manufacture its polio vaccine.
Types II and III were created in a similar fashion.
More fuel for antivaxxers (Score:3)
Live is not about cheap (Score:1, Troll)
You do not want polio (Score:2)
My grandparents would talk about it. It killed people or maimed them. I know people that had it and they couldn't walk for years and they were never the same after that. Covid has nothing on polio
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THIS.
My parents grew up around polio. My Dad told me that each fall he would count the number of other kids in school who didn't return - because they came down with polio over the summer and were paralyzed. Permanently.
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But I have something called an immune system /s
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Statistically, the poliovirus has a similar mortality rate to Covid-19.
Perhaps, but there is a big difference between a stuffy nose and spending the rest of your life in a wheelchair. I'll take covid over polio (which I have, at least twice).
I wonder if covid-19 would be taken more seriously by the public if it affected more kids like polio did.
Yes, and that is what we have been saying all along. Closing down schools for two years would have made sense if there was some level of risk to children.
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The parent of the child is free to make the decision to keep their kid home. Same with masks. Nobody says you can't wear one.
One of the worst part of news like this (Score:2)
One of the worst part about news like this is that you know there are going to be anti-vaxxers who are going to try to spin this into anti-vax nonsense.
Overview of polio caused by oral vaccine (Score:4, Insightful)
There are two types of polio vaccines. One which is injected, and the other is oral.
The oral one is more popular, specially in developing countries, because of ease of administration.
It is basically a live attenuated virus. Attenuated is done by passaging the disease causing virus in animals for many generations until the mutations accumulate and cause it to lose its virulence. If it retains its antigenic properties but loses its disease causing virulence, then it is suitable as a vaccine.
By administering it orally, it infects the gut mucosa, and there is good immunity there, which is good, since polio is a fecal-oral route virus.
What we are seeing now is that, since it is a live virus, it continues to mutate (as all viruses do), and reverts to a virulent strain. It is excreted in the feces, and infects other people. If those people were not vaccinated, then it can cause disease.
So the problem is that if the population is not well covered, then the virus will eventually go to unvaccinated individuals, and a very small percent will exhibit disease.
There are multiple efforts underway on avoiding this reversion to virulence, but nothing that is FDA approved yet.
Listen to This Week In Virology #756 [microbe.tv] around the 43 minute mark for details.