On Saturday I wrote about the fact that the anti-vaccine movement has never been about children, and it hasn’t really been about vaccines. It’s about privileged parents and how they wish to view themselves, specifically as defying authority and empowered by self-education. This is why efforts to educate anti-vax parents about the science of immunology has been such a spectacular failure. It is not, and has never been, about the science.
That does not mean that anti-vaccine parents understand the science behind vaccines. They emphatically do not, and it is this lack of understanding that undergirds most of their philosophical claims.
As a threshhold matter, if you ever want to stop anti-vaccine parents in their tracks, ask them to explain how vaccines work. They can’t do it!
I don’t mean simply how vaccines lead to immunity. That’s relatively straightforward in any case. Vaccine stimulate the production of antibodies. Antibodies are proteins that recognize specific bacteria or viruses and bind to them, thereby signaling to other immune cells that they are targets for swift neutralization. Each antibody binds to a specific site on a specific bacteria or virus.
Everyone with an intact immune system makes antibodies. We can make them in response to the disease or we can make them in response to the vaccine. The difference is that the disease can kill us before we make enough antibodies to kill it. Vaccines give us a huge head start. We make antibodies to the specific virus or bacterium after being exposed to an inactivated part of (or whole) virus or bacterium. Then if and when we are attacked by the pathogen, we ramp up production of antibodies before the virus or bacteria can multiply enough to kill us.
That’s how vaccines lead to antibodies, but that’s NOT how vaccines work to protect everyone’s health.
The way vaccines work to protect health is by making it impossible for pathogens to jump from person to person.
Even the best vaccines are not 100% effective, and we can’t vaccinate 100% of the population. For example, babies can’t be vaccinated for specific diseases until they can mount the appropriate antibody response. Immuno-compromised people may not be able to mount an immune response at all.
In other words, if vaccines needed to be 100% effective to work, they wouldn’t work in the real world.
Instead, vaccines work by dramatically reducing the chance that an infected person will encounter an unprotected person. As I explained last week in Anti-vaxxers, the real welfare queens:
Imagine that little Ainsley comes in close contact with 10 children per day. Now imagine that Ainsley develops diphtheria. Who is likely to catch diphtheria from Ainsley? If 99% of children are vaccinated and the vaccine is 95% effective, the odds are low that any of the 10 children she comes in contract with could get diphtheria. Thus, the outbreak of diphtheria ends with Ainsley (though it may end poor Ainsley’s life).
Now imagine that only 50% of children are vaccinated against diphtheria. That means that half the children are likely to be susceptible, and therefore diphtheria is almost certain to be transmitted. And since the children who catch diphtheria from Ainsley are going to expose additional children who aren’t vaccinated, the disease begins to spread like wild fire.
In other words, in 2015 if Ainsley’s mother doesn’t vaccinate her against diphtheria and she never gets diphtheria, it’s NOT because she was breastfed, eats organic food and has a strong immune system. It’s because herd immunity ensures that she’s never exposed to diphtheria.
When parents refuse to vaccinate their children, herd immunity is disrupted and deadly diseases can spread.
This cartoon on the awesome Facebook page of Refutations to Anti-vax Memes makes it easier to understand the issue.
The people holding the umbrellas are everyone who has been vaccinated (or has had the actual disease and survived). You can see that there’s room for more than the umbrella holders under the umbrella, just as vaccinating everyone who can be vaccinated protects those who can’t be vaccinated.
You can also see a person announcing that he doesn’t feel any rain so there’s no need for an umbrella. That’s just like the anti-vax parents claiming that they’ve never seen a person suffering from a vaccine preventable disease so there’s no need for vaccination.
You can also see that the belief that the rain has stopped is wrong, just as the belief that vaccine preventable disease are no longer a threat is also wrong.
Now imagine that half the people holding the umbrellas closed them and dropped them. A lot of people would get wet, not just those who aren’t holding umbrellas, but also those who have malfunctioning umbrellas. That’s what happens when herd immunity is compromised. Both the vaccinated and the unvaccinated are threatened (although the threat to the vaccinated is much smaller than the threat to the unvaccinated).
It’s easy to see how refusing to vaccinate hurts everyone, not just the children who aren’t vaccinated.
It’s also easy to see how the anti-vax parents whining that there’s no need for vaccinations are clueless. They don’t understand that they are standing under the umbrellas. So not only are anti-vaccine parents often wrong about the science of vaccines, their lack of understanding undermines their philosophical arguments supporting the refusal to vaccinate.
The primary philosophical argument deployed by anti-vaccine parents to defend their decision not to vaccinate is predicated on the scientific falsehood that vaccines work by being 100% effective and therefore, the only children threatened by their failure to vaccinate are their children.
But that’s not how vaccines protect public health. They work by dramatically reducing the chances that a vaccine preventable illness can travel through a population.
So when you refuse to vaccinate your own children, you aren’t just hurting them; you’re hurting many others.
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