Whenever faced with obvious cases of denialism (creationism, germ theory denialists, –and relevant to this post–anti-vaccination proponents), experience has shown me that there is almost always a fundamental misunderstanding about which their conclusions are drawn from. To really understand how vaccines work one needs a basic understanding of how acquired immunity (also known as both active and adaptive immunity) works.
On the surface of every cell and every virus there are molecules made up of sugars and or proteins. The arrangement and structure of those molecules are unique to that organism and its progeny. These molecules are what illicit an immune response (specifically the generation of antibodies which fight disease). When they do this they are known as antigens (short for antibody generation).
When a foreign microbe makes its way into your body it is –relatively soon–greeted by a type of white blood cell known as a macrophage. These macrophages engulf the invading microbe in a non-specific immune response. That means they “eat” whatever does not share their unique cell surface molecule. I always liked to think of the surface molecules/antigens as name tags. Your body is a very elite party where anyone who does not have the same name tag as everyone else gets the crap beaten out of them; where the macrophages act as the bouncers. Here is an absolutely beautiful video of how a macrophage works (this is actually a neutrophil and not a macrophage. The process, however, is very similar).
Once the macrophage engulfs the invader it digests everything but the invader’s antigen; the macrophage uses these antigens to signal the production of different immune cells specific to that invader.
One of these immune cells (B lymphocytes) secrete antibodies which, when they come in contact with anymore invaders, attach themselves to the invader’s antigens in sort of molecular puzzle piece fashion. This shuts the microbe down and signals for its quick demise.
[A number of other lymphocytes are generated which play other roles in the immune system, but I think –relevant to this post–the B cells are the most pertinent.]
Congratulations. You are now immune to that specific invader.
While all this went on for 2 weeks (4 if you’re me) you were subjected to whatever effect that microbe’s toxin has on a human being. The effect from said toxins can be anything from a runny nose to a high fever and even death -depending on what it is.
Vaccines work in the same manner, only the aim with them is to get the antigens needed for the production of antibodies to the macrophages while not subjecting the body to the microbe’s toxins. This is done a few different ways. The most common of which involves deactivating the microbe’s toxins or rendering the microbe incapable of replication. There is a new method in development (which I will probably post on later) using genetic engineering that I’m sure, in time, will be the future of all vaccinations.
So why all the controversy? For as long as there have been vaccines there have been anti-vaccination proponents (antivaccs). One of the oldest claims behind the antivacc movement is the notion that vaccines are unnatural. I’m of the frame of mind that we’re all a part of nature (being animals derived from it) and making vaccines is an adaptive function of our evolved brains. That aside, bear in mind we are using our bodies natural immune system to develop resistance to these invaders; we’re just taking death and illness out of the equation.
One claim that seems to remain is the notion that vaccines don’t work. This is simply not true. The lowest –that I could find amongst reasonable studies–percentage of effectiveness is 35% among those over 65, and this only seems to occur in influenza trials where test subjects are tested for non-specific influenza symptoms. This means they are tested for any flu-like symptoms, not just the influenza strains they were vaccinated for.
When tested for specific strain resistance (like that of chickenpox strains) we find effectiveness to be between 94% and 100%. So to say that vaccines “don’t work” is demonstrably false.
One of the most recent antivacc assertions is that they can cause autism. In 1998 a paper was published in the Lancet, by one Dr. Andrew Wakefield, suggesting that neurological disorders such as autism were the result of the measles, mumps and rubella (MMR) vaccine. Wakefield developed a small (but loud) following of physicians, celebrities and uninformed patients. Those most notable amongst them were Dr. Herman Hugh Fudenberg, who had been part of the antivacc movement long before Wakefield. Fudenberg’s claim was that autism was caused by thimerosal used in MMR vaccines. And Jenny McCarthy, former playboy model turned “actress”.
Fudenberg’s assertion comes from the notion that thimerosal is metabolized by our bodies into mercury. “Wait mercury, isn’t that the stuff that causes brain damage?” In high doses, yes. Methylmercury is a bioaccumulative toxic substance. That is we absorb it at a rate greater than we can get rid of it, and the accumulation brings it to toxic doses. This is why prolonged mercury exposure causes brain damage. But the thing is thimerosal is converted to ethylmercury. “What’s the big deal, there’s just one letter different between the two.” Yes and that difference is similar to the one found between methyl alcohol (gasoline) and ethyl alcohol (whiskey and beer). As it turns out (according to current evidence) ethylmercury is not bioaccumulative and does not pose the same threat methylmercury can pose.
Despite those facts many antivaccs still claim that thimerosal and MMR vaccines cause autism. As it turns out subsequent research was done by both government and independent researchers, both of which showed there was no causation between thimerosal –or MMR vaccines–and autism. Furthermore, as it turns out the MMR vaccine never even contained thimerosal to begin with.
But what about Wakefield’s research? Well as it turns out 10 of his 12 co-authors retracted Wakefield’s interpretation of the data. And in 2004 investigative reporter Brian Deer published an article in the London Times claiming that Wakefield’s patients for the trial had been specially recruited by a lawyer preparing for a lawsuit against the makers of the MMR vaccine. If this is indeed true, Wakefield is an even more sub par researcher than I had thought.
Dr. Fudenberg has an even more dubious past. In 1995 he went before the South Carolina Board and was found guilty of “dishonorable, unethical, and unprofessional conduct“. As a result he lost his ability to prescribe drugs for the remainder of his career. In 2004, when his license expired, he applied to have it reinstated. Evidence concerning a psychiatric evaluation he underwent deemed him “unfit to practice medicine”, and he was allowed to withdraw his application. Despite his lack of a medical license Fudenberg continues to give medical advice such as: record reviews ($750 an inch), ordering medical tests and interpreting their results ($750).
Of all the mysteries concerning human behavior one that I will probably never understand is how people can take scientific, medical and political advise from celebrities -specifically actors and actresses. That is not to say they’re all complete morons, but they can hardly be considered experts.
No celebrity –that I know of–has had their hands in the cookie jar of misinformation concerning vaccines, autism (and some other dubious claims) more than Jenny McCarthy. In fact her own website bares the subtitle “Autism is Reversible” (unfortunately to date it is not). McCarthy has gained so much publicity through her antivacc campaign that there is now a website dedicated to the number of preventable deaths that have occurred (amongst the unvaccinated) since she began to speak about them in public.
McCarthy’s situation with her son –who was diagnosed with autism–is unquestionably difficult for her. And while I’m sympathetic to her situation if she is going to tout medical claims she must be held to the same scrutiny as the scientific community. I’m also focusing on her specifically as she has publicly made a number of “raising the bar/moving the goalpost” fallacies that so many antivaccs make.
Though McCarthy still maintains (on her website) that mercury in vaccines is a major factor in autism, when confronted directly she typically moves on to other things found (and some not) in vaccines, all of which are way below toxic doses. I’ll address two of them.
1. Formaldehyde -It is true that some vaccines contain residual amounts of formaldehyde, but they are way below EPA limits. As it were, the human body naturally contains a minimum of 2.5 micrograms of formaldehyde for every milliliter of blood, as it is essential to the synthesis of DNA and amino acids. Therefore the amount of formaldehyde naturally occurring in a 2 month year old infant (at 5kg and 85ml of blood per kg) is about 1.06mg –a significantly greater amount than those found in vaccines. Additionally, doses 600 times greater than the amount found in vaccines have been given safely to rats.
2. Antifreeze -This is completely false. No vaccines contain ethylene glycol (antifreeze).
When faced with the evidence concerning that McCarthy typically follows with the declaration (although it’s her lead in the Larry King interview) “It’s too many too soon”, implying that a child’s immune system can not handle the amount of antigens being given during their vaccine schedule. Well as it turns out –based on antibody variable gene regions–we can handle on the low end 1 billion (that’s BILLION with a B) antibody specificities. The largest vaccine regimen contains enough antigens to produce 100 specific antibodies.
One of the assertions that will probably never die amongst antivacc proponents –specifically about influenza vaccines–is anecdotes such as “I don’t get vaccinated and I never get the flu”. Well there is a reason for that. It’s called herd immunity. When the majority of the population is vaccinated the chain system viruses depend on for transportation (that is person to person contact) is broken. So effectively, those of you who do not get vaccinated and still don’t get the flu are being moochers -GET A JOB YA MOOCH *humor*. Unfortunately your mooching is posing a risk for others. There is a small group of individuals that can not get vaccinated and they depend on herd immunity to avoid disease. If you’re not going to get vaccinated for yourself, at least do it for them.