Herd Immunity In Action: HPV Vaccine

Herd immunity-- If a lot of people are protected from a pathogen then the people who arent protected, are still protected.  The higher the percentage of 'protected' people, the better herd immunity works.

Here is a simple animation of how herd immunity works.

While we generally think of herd immunity as it relates to the very young/old, immunocompromised, those who cannot get vaccinated for medical reasons, this concept matters to all of us.  Like I said in my talk at FreeOK last year-- your immune response to a vaccine is random, so there are some of you reading this article whos parents dutifully got them their MMR vaccines as babies, and yet you do *not* have a protective immune response for measles.  You wont know you happened to react this way until some anti-vax parents (read: terrible parents) expose you to their measles infected offspring.

While the ideal levels of vaccine coverage for herd immunity are usually >80%, a paper was just published in Pediatrics that illustrates just how dramatic the effects of herd immunity can be, even if coverage rates are low:

Vaccine-Type Human Papillomavirus and Evidence of Herd Protection After Vaccine Introduction

These researchers followed a group of girls/young women who did not get the HPV vaccine, and another group that got at least one dose of the HPV vaccine (now, this is important, the HPV vaccine requires three doses for it to work best, so the percentages in this paper are low-balling what we would expect if girls were getting all three doses).

The young women who got at least one dose of the vaccine saw a reduction in vaccine-HPV infection of ~70%.  Again, not bad considering some participants only had one of the three recommended doses.

Heres the cool part: The young women who had not gotten the HPV vaccine saw a reduction in vaccine-HPV by ~50%.

The protected women prevented transmission of HPV to males (this study was restricted to mainly heterosexual contact), which prevented those males from infecting the unprotected females, to the tune of a 50% reduction in vaccine-HPV lesions.

How high would both of those numbers shoot up (70% and 50%) if the protected group was getting all three doses?

How high would that 50% jump if more women were getting all three HPV shots?

Its heartening to know that even if anti-vax or radical religious parents wont protect their children from deadly diseases (or unfortunately, the parents who want to, but cant protect their kids because of the expense of the HPV vaccine series), science will protect those kids anyway.


More like this

"Heres the cool part: The young women who had not gotten the HPV vaccine saw a reduction in vaccine-HPV by ~50%."

More vaccine fantasy, and a computer simulation so it must be true!

"The increase in nonvaccine-type HPV in vaccinated participants should be interpreted with caution but warrants further study." Read it for yourself in the abstract, stunning!

So they just displaced the condition, which may end up producing more disease but of course because it's a medical scientific study we only want the design results, not the potentially catastrophic fall out from a failed vaccine.

Bit like Polio vaccine in India, no wild polio in the vaccinated but now 2x lethality flaccid paralysis in the same amount of people! Bingo that's a result.

If men carry the virus, why not vaccine them also ?

By RadTransf (not verified) on 11 Jul 2012 #permalink

your immune response to a vaccine is random,

How unscientific.

You wont know you happened to react this way until some anti-vax parents (read: terrible parents) expose you to their measles infected offspring.

Or a vaccinated persons because Merck committed fraud. Read: dishonest scientists and gullible newbie scientists like the author.

By augustine (not verified) on 11 Jul 2012 #permalink

Augustine, what, exactly, is unscientific about Abbie's description of the immune response? Did you watch her talk from FreeOK last year? Do you understand anything at all about biology? Or are you just a typically ignorant denialist?

By Optimus Primate (not verified) on 11 Jul 2012 #permalink

Did you watch her talk from FreeOK last year?

Yep. I watched it. The whole thing.

Augustine, what, exactly, is unscientific about Abbie’s description of the immune response?

The randomness!

By augustine (not verified) on 11 Jul 2012 #permalink

I don't know if you have seen this yet:
Schoolboys to get Gardasil vaccine

The Queensland scientist who created the cervical cancer vaccine has hailed the decision to fund immunisation for boys.
In what has been billed as a world-first, Australian schoolboys are set to begin receiving injections of the Gardasil vaccine to protect against conditions such as genital warts and some cancers.
Professor Ian Frazer backed the decision, saying Australia was leading the way on this public health front.
“The addition of the HPV vaccine for young males on the National Immunisation Program is good news for the young men of Australia,’’ he said in a statement.
“This is a very safe and effective vaccine and vaccinating boys will also further benefit women who have not been vaccinated through herd immunity.’’

By Michael Kingsf… (not verified) on 11 Jul 2012 #permalink

augistine wrote The randomness!

There is an enormous degree of randomness to the generation of an immune response. The cells which form antibodies (B-cells) and which form T-cell receptors (TCRs) - T-cells, are the cells that actively recognize the antigens found within a vaccine/pathogen/allergen/etc.

The antibody/TCR receptors are formed through a process which is random - you randomly select gene segments (from large arrays of segments), and splice them together to form a functional gene. The cutting process is somewhat random - the cut sites are not distinct, with cutting occuring in regions rather than at an exact site. The joining of the cut DNA is truly random, with an enzyme named 'TdT' adding random base-pairs of DNA to the splice site. In the case of antibodies (but not TCRs) there is then a series of random mutagenesis steps on the assembled gene.

In the end, this reaction (which occurs individually in each T & B cell) produces a novel receptor. The binding site of the receptor is made up of the splice sites in the DNA - i.e. the binding sites are completely random, being generated by a combination of random(ish) cutting, random base-pair addition, and random mutation.

Responding to a vaccine requires that, at the time of vaccine administration, you have a B-cell with the right BCR and a T-cell with the right TCR at a place where they can both encounter the antigen (as you don't get an immune response unless these cells cross-activate each other). Because of the random nature of the antibody/TCR generating process, there is a portion of the population who will not have the appropriate responder cells. Likewise, the exact epitope(s) in the antigen any paritcular individual responds to can be different than another individual, individual 1 may have a randomly-generated receptor that recognizes a different part of the antigen than individual 2.

So Abbies is indeed correct when she says our response to vaccines is random - the receptors are generated through randomization processes, the portion of the antigen identified by those receptors varies depending on the specific receptors formed (as does the strength of the resulting immune response), and there is a portion of the populaiton whom - through random chance - will lack the right antibody/TCRs to respond to the vaccine.

She is both correct, and is scientifically accurate, in her description of vaccine responsiveness as being "random".

Bryan & Optimus,

Augie is a troll with no clue about biology. I can guarantee he skimmed the first two sentences of your responses and then gave up. Feeding the troll may be funny but it's futile to try to explain this stuff to him.

By Poodle Stomper (not verified) on 12 Jul 2012 #permalink

Yaaay for herd immunity.

I'm pretty allergic to uncooked eggs (and somewhat allergic to cooked ones) so I always skip out on the annual flu shots, as they make me more ill than a case of the flu.

It's good that I'm somewhat protected by people who are able to partake of the vaccines.

But it's detestable that some fools are permitted to keep their children unvaccinated because of ignorance, false information and superstition.

I call that "child abuse" myself...

... but I suppose it's a long-standing tradition that parents have the "right" to abuse their kids any way they see fit.

.... meh....

... sometimes tradition is overrated.

By Bob Powers (not verified) on 12 Jul 2012 #permalink

The lack of herd immunity for measles is making me consider closing my car windows when I drive past a school.

Poodle Stomper & Brian & Optimus, although trolls shouldn't be fed, I appreciated the explanation. As a non-biologist, this kind of responses is essential for me to continue appreciating the blog itself. If this kind of remarks would be without rebuttal, I would be unable to find out myself whether the remark is correct or just nonsense. So, thanks !

I'm not against vaccines and think that they do work for the majority... But certain vaccines are not necessary for everyone, such as the flu vaccine. The risks far outweigh the benefits unless your immune system is compromised. Most of the ingredients in vaccines are poison. Again I'm not against them, I just think that we shouldn't run for a vaccine for every little disease.

Dude -- Im guessing that the families of the 41000 people annually who's deaths are attributed to influenza would disagree with your assessment of the necessity of the flu vaccine. To the contrary of your assertion, the benefits far outweigh the risks. While its true that most (I would say all) of the ingredients in vaccines are poison if taken in sufficient quantities, the same can be said of your breakfast cereal. Fortunately the ingredients in both substances are used in quantities far below their lethal dose.

What Dave said-- vaccines are the best and surest way to avoid specific diseases.

Unless someone has a specific medical reason to avoid them, vaccines should be administered where available.

As my epidemiologist colleges have told me many times, the poison is in the dose.

Too little salt in your diet will kill you just as surely as too much.

By Bob Powers (not verified) on 13 Jul 2012 #permalink

Dave could you tell us how may influenza deaths of the 41,000 could be prevented if only 100% of the population had gotten an influenza vaccination?

By augustine (not verified) on 13 Jul 2012 #permalink

Augustine... since the vaccine is around 70% protective against infection, I'd make that 28,700 lives saved.

Wrong! The 70% is wrong. It used to be said that it was 70-90% efficacious in the healthy (most likely not going to die) and 30-40% in the elderly(most deaths). Since then it has been discovered that this top number is about 60% in the healthy. No telling how low it is in the elderly and immune compromised.

By augustine (not verified) on 14 Jul 2012 #permalink

If the vaccine actually were 70% efffective then you would see a massive drop in influenza deaths. But that doesn't happen for a variety of reasons. Can you explain why 41,000 die year after year after year? And don't give me the "not enough people take the vaccine" unless you can show that massive increases of vaccine uptake have resulted in massive decreased in influenza death. Good luck!

By augustine (not verified) on 14 Jul 2012 #permalink

Don't you think that millions take the vaccine?

By augustine (not verified) on 14 Jul 2012 #permalink


The risks far outweigh the benefits

What are the risks of influenza vaccination? A sore arm?

Most of the ingredients in vaccines are poison.

What like water and squalene? Squalene is produced by the body. There are very few substances that are poisonous in the amounts injected during a vaccination - and none are found in the vaccine. Not very surprisingly, doctors are aware of what substances are toxic in tiny doses and don't include them in the mixture.

Again I’m not against them, I just think that we shouldn’t run for a vaccine for every little disease.

A little disease like influenza? It's far from a "little disease", killing as many as 50,000 people per year in the US alone. Yes, many of those people are elderly (90% say). That still leaves 5,000 non-elderly people killed by influenza. Plus, why is it "OK" for old people to die? I love my grandma, I would be very upset if she died from a completely preventable disease. Do you hate old people?

Plus, why is it “OK” for old people to die?

It's not "OK" for old people to die but that's a strawman argument saying that if one criticized mass vaccination it is akin to letting old people die.

The vaccine doesn't work very well in the elderly and the immune compromised.

There are not 50,000 influenza deaths. All pneumonia deaths are not called by influenza. You'd also have to show the exact number of deaths caused by the vaccine strain in order to project how many you think would be "vaccine preventable" deaths. Then you'd have to minus all of the ineffective vaccines.

So many confounders. So little evidence and science.

By augustine (not verified) on 16 Jul 2012 #permalink

Augustine, the elderly and immune compromised are exactly the ones who benefit the most from herd immunity. If the darling grandkids don't get sick, they won't get the grandparents sick when they visit.

Herd immunity is a farce with the flu shot. Never happened. Not going to happen.

By augustine (not verified) on 17 Jul 2012 #permalink

augustine is yet another buckthetrend.

Probably trying to paint actual people against big pharma as 100% idiots.

Facts and questions! One who calls others idiots doesn't like them.

By augustine (not verified) on 17 Jul 2012 #permalink

I see lots of claims, and very few links to actual...

... facts.


By Bob Powers (not verified) on 18 Jul 2012 #permalink

Natural News and the Daily Fail?
You lose, Augie.

By Julian Frost (not verified) on 19 Jul 2012 #permalink

Ad hominem. YOU lose!

By augustine (not verified) on 19 Jul 2012 #permalink

Augustine is correct that one should not dismiss a source without examining it (though I don't think that's actually an Ad Hominen). Having said that, I think he's misread the Daily Mail India report. The lead researcher is quoted as saying that they can't rollout unless they can monitor the safety and efficacy of the vaccine in India and The Indian monitoring system isn't sufficient.

By Niche Geek (not verified) on 19 Jul 2012 #permalink