The morning my 2-month-old son received his first round of immunizations, I felt sick. I could not shake the feeling that there was a dormant, microscopic defect in my child that through either my ignorance or carelessness would gain a foothold in his body. Most of the mothers I know were hesitant vaccinators, choosing to immunize their children but not following the schedule recommended by the Centers for Disease Control and Prevention. Repeatedly I heard responsible, thoughtful women argue that vaccinating on schedule risked overloading a developing immune system with toxins.
I was already too familiar with medical uncertainty. Nine years ago, my husband was diagnosed with multiple sclerosis, an autoimmune disease that debilitated and hastened the death of his maternal grandmother as a young woman. Hearing of his diagnosis, I felt that one of the unknown quantities that we all grapple with in life wasn’t unknown anymore. It had a name, even an abbreviation: MS.
When I became pregnant last year, his MS took on another dimension. Would my baby inherit the chronic illness? Could vaccinations, as many vaccine skeptics purport, trigger an autoimmune response in a little body where predisposing genetic factors were at play? Whereas in my role as partner, my husband’s MS seemed to me proof of life’s uncertainties, in my new life as a parent, bewildered and awed by the responsibility, I wondered whether I would be an inadvertent accomplice to unleashing my unborn child’s genetic vulnerability. Because autoimmune diseases are thought to result from environmental conditions interacting with an underlying genetic weakness, I found myself especially susceptible to the “don’t overwhelm the young immune system” line of reasoning. I am not alone.
Nearly 5 percent of Americans have an autoimmune disease. The speculation as to why has included vaccines. In response to questions posed by concerned parents in the early 2000s, studies emerged addressing whether vaccinations, as they are currently scheduled, deluge the immune systems of young children, ultimately putting them at risk for developing autoimmune illnesses. A comprehensive investigation by the immunization safety review committee of the Institute of Medicine found no evidence to support the claim that children’s immune systems are incapable of handling the schedule.
Conversely, we know that the immunological burden posed by the antigens present in vaccines are orders of magnitude smaller than those a child’s immune system encounters during routine ear infections. While a causal relationship has long been suspected between the hepatitis B vaccine that is routinely given to infants and MS, no link has been substantiated. However, a very small number of vaccines have been associated with an increased risk of developing autoimmune responses, such as theobserved increased incidence (PDF) of Guillain-Barre syndrome among those immunized against the 1976 swine flu outbreak. Yet harmful attitudes toward vaccination persist — in pockets, at least — and they stem from more than ignorance.
As parents, we are good at identifying fears. What we are not good at is assessing the likelihood of those fears becoming reality or the logical chain that would make them possible. What we fear most are not the threats that are unpredictable — car accidents, terrorist acts, Floridian sinkholes — but those that we feel we can control. However, in evaluating those fears, we too often deem implausible threats (for instance, that vaccination leads to autism or autoimmune illness) plausible. Fear is a potent motivator of confirmation bias.
The public health aspect of this debate has been well documented. While the unvaccinated pose little threat to the vaccinated, they put infants who are still too young to be immunized against airborne illnesses as well as those with compromised immune systems at risk of pneumonia, brain damage and death. As the mother of a 4-month-old, I am terrified of airborne illnesses for good reason and glad that the Disneyland measles outbreak taught the country a lesson about herd immunity.
Despite recognizing the broad-stroke arguments, my fears remain. The epidemiological studies needed to prove or disprove a causal relationship between vaccinations and those with a predisposition to autoimmune illness are problematic (PDF), requiring complicated analyses of large and often difficult-to-interpret data sets.
Nevertheless, my family’s decision is to immunize on schedule — even though a very small risk exists for my child. Am I an irresponsible parent? Certainly some will think so. But what kind of parent would I be if I allowed the inflated fear of all risks, no matter how small, to direct the health care decisions I make for my child? In the brief time that I have been a parent, I have discovered that this job boils down to things I think I can control and things I outright can’t. Having debated the issue with my inner worrier, I’d argue that the choice not to vaccinate is more of an explicit bow to parental anxiety than to children’s well-being. By and large, it is not immune systems that are being overwhelmed but parents.