Reuters/Brian Snyder
Sen. Rand Paul (R-Kentucky).
"The fact of the matter is, we have extremely well documented proof that there's no autism associated with vaccinations," Carson said at the debate. "But it is true that we are probably giving way too many in too short of a period of time."
Paul's "second opinion" on Carson's diagnosis? "I'm also a little concerned with how they are bunched up," he said. "My kids had all their vaccines, and even if the science doesn't say that bunching them up is a problem, I ought to have the right to spread my vaccines out a little bit."
Presumably this argument is based on the idea that too many vaccines in too short of a time is too big of a load on the immune system of an infant. But this argument isn't logical. Our bodies are exposed to the same kind of immune system stressors that are in vaccines constantly just by living in the world.
Last year, Dr. Paul Offit, Chief of the Division of Infectious Diseases and the Vaccine Education Center at the Children's Hospital of Philadelphia, gave me one of the best explanations I've ever heard about why this argument is just plain wrong.
In reality, we (yes, even babies) are exposed constantly to things that activate the immune system: individual proteins or pieces of proteins that make up bacteria, viruses, fungi, and everything we are exposed to.
When these things make their way into our bodies, our bodies respond by activating the immune system into making more immune molecules and immune cells.
Our bodies do this all day, every day. Here's what Offit told Tech Insider back in March of 2014:
When you are in the womb you are in a sterile environment. When you enter the birth canal and the world you are not. Very quickly you have living on the surface of your body trillions of bacteria, to which you make an immune response.
A single bacteria has between 2000 and 6000 immunological components ...
The total number of immunological components of all 14 [vaccines] given in the first years of life is maybe 160.
It's nothing. It's a literal drop in the ocean of what you encounter. If you were overwhelmed by vaccines you would not survive, given the trivial immunological challenge it is compared to what you encounter every day.
The New York State Department of Health says the same: "Children fight many more antigens on a daily basis than they fight when given any combination of vaccines on the vaccination schedule."
NIAID / Flickr
A healthy human t-cell is shown in this scanning electron micrograph image.
The alternative, spacing the same vaccines out over longer periods of time, is not a good option. As Dr. Offit told PBS's Frontline:
Every time a vaccine comes onto the schedule - a new vaccine - the FDA makes the company prove that that vaccine doesn't interfere with the safety profile or the immunogenicity profile of the existing vaccine, and vice versa. So the schedule is very well tested.
I think that when you choose your own schedule, you're choosing something that isn't well tested, where you don't know whether or not the immune response is the same; you don't know whether or not the safety profile is the same.
Plus, as the Autism Science Foundation notes, when researchers "looked at children who received vaccines and those who didn't, or who received them on a different, slower schedule ... there was no difference in their neurological outcomes."
Not only that, but delaying vaccines means that child is more at risk of catching diseases like measles, since they'd spend more time not vaccinated. As Offit points out in an article in the journal Pediatrics, alternative vaccine schedules go against the advice of the American Academy of Pediatrics, the Centers for Disease Control and Prevention, and the American Academy of Family Physicians.
While some vaccines may need to be delayed for certain children, there is no argument that all vaccines should be spread out of an indefinite length of time at the whim of a parent.