The recent re-emergence of measles in the United States following a 15-year period of occasional cases provides a compelling example of an unresolved societal tension in public health: that between the value of autonomous decision-making and the need for social responsibility. The outbreak—more than 700 cases since January 2014—reveals not only this tension, which also plagues other arenas of health care reform.

It also reveals the tenacity of doubt about vaccine safety that has led to a tipping point in undermining herd immunity. (That is, within a community, high rates of immunization protect both individuals and the community as a whole, including those who are not immunized, by limiting the disease’s ability to spread; when too many people opt out, however, that overarching protection wanes.)

Why aren’t certain communities of generally affluent and well-educated parents in the U.S. following medical advice, even after scientific reports have confirmed that there is not a causal link between vaccines and autism and other developmental disorders? Can the value of childhood vaccination as a critical public health measure outweigh the value of the right to parental choice? The answers to these questions are found in contemporary parent sensibilities about trust, doubt, and individual ethics.

Doubt has become central to the idea of parental responsibility in the face of health care decisions. That doubt, which includes skepticism about medical expertise, heightened risk awareness, and a generalized lack of trust in government, has made it difficult for clinicians and researchers to dislodge two notions that have penetrated the culture: that there is a vaccine-disease link and that vaccines are dangerous.

The Crisis In Trust And Increase In Doubt

By the late 1980s and early 1990s the societal emphasis on personal responsibility for health and health care converged with a widespread crisis in trust in American institutions, including the medical establishment. During that same period, neurodevelopmental problems acquired a new demographic face. The apparent rise in the incidence of children affected with autism and other neurodevelopmental problems coincided with the increase in the number of childhood vaccines given routinely in the U.S.

In 1967, U.S. infants and toddlers received five different vaccines for a total of seven diseases: smallpox, DPT, polio, measles, and rubella. (In 1971 the smallpox vaccine was officially dropped, due to the growing success of smallpox eradication programs around the globe.) Throughout the 1990s, because of the success of vaccine research and development, new vaccines were added to the schedule.

In 2006, nine vaccines for a total of 13 diseases were recommended for infants and babies by the American Academy of Family Physicians and the Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization practices. Today, 10 vaccines for 14 diseases are recommended (this excludes tetanus and flu shots). Each of those vaccines requires two to five doses for maximum protection. It is recommended that children have initial doses prior to age two.

This temporal correspondence of more vaccines and more developmental disorders gave rise to an increased sensibility, beginning in the late 1980s, that vaccines are something to learn about, talk about, and perhaps worry about. Since then vaccine talk is simply part of the early child-rearing experience. It occupies a great deal of space in parents’ groups, parents’ blogs, and websites.

Learning about vaccines, deciding which to accept or decline, and whether and when to vaccinate one’s children are absolutely inescapable elements of new parent awareness and responsible parenting. Individual stories of children who were healthy one day and then regressed following a shot circulate widely; those stories have been and remain a staple of vaccine talk and they inflame doubt. They are accompanied by talk about “too many vaccines” and the good of “natural” immunity from the disease itself.

Physician talk—about the distinction between correlation and causation—does not quell the power of these topics for parents who hold firmly onto their opinions.

The importance of individual responsibility for health together with the widespread worries about a connection between vaccines and childhood disorders served to underscore popular interpretation of two events that unfolded in 1998 and 1999.

First, the now discredited Wakefield article in The Lancet appeared in 1998, suggesting a causal connection between the MMR vaccine and autism. Second, the Food and Drug Administration (FDA) announced in 1999 that infants who received the recommended number of vaccines might be exposed to cumulative amounts of ethylmercury (contained in the vaccine preservative thimerosal) that exceeded federal safety guidelines. (Data reviewed by the FDA and CDC from 2000 to 2004 did not demonstrate convincing evidence of toxicity from doses of thimerosol used in vaccines.)

In her book-length essay, On Immunity, Eula Biss suggests that by 1999 the question for parents “...was whether inoculation was a risk worth taking.” To address that question, parents searched for more information.

The Imperative Of Individual Responsibility

The moral imperative of individual responsibility for risk assessment and reduction, a hallmark of neoliberal society in general, guides parental decision-making about childhood vaccination. Today, in health and in life, one knows that to act responsibly one must pick and choose among sources of information and decide which of them are authoritative.

Because responsible parents are mindful of the potential health risks in food, toys, cribs, paint, baby formula, etc., and are acutely aware of the extent of environmental toxins, even in breast milk, they are predisposed to vigilance about anything that goes near a baby or into a baby’s body.

Between 2006 and 2009 I interviewed two dozen parents about their responsibilities in relation to childhood vaccination, their ideas of a connection between vaccines and autism, their thinking about risks and citizenship, and their ambivalence about medical advice.

One mother of an unvaccinated baby echoed many during those years when she noted: “Knowing that there could be any risk whatsoever of autism, of mercury toxicity, anything, I think, immediately propels you into this domain of reactivity. So here, in our lives with our baby, in this very intimate sphere of our lives, questioning is, for me, imperative.”

The conversations and the questioning remain strong today.

For many, vaccine safety doubt, specifically, pervades the ethical task of deciding how to live among burgeoning kinds of information, ever-emerging truth claims, media sound bites, celebrity personal stories, and scientific knowledge. Within that doubt, parents feel forced to rely on themselves and to negotiate their relationship to medical expertise.

The recent measles outbreak, following earlier outbreaks of pertussis, is evidence of how doubt sustains and enables its own persistence. A groundswell of protest has emerged from some parents who vaccinate their children. They posit that those who do not are harming their communities.

Yet parents who are not swayed by public pressure, medical education, or disease outbreaks to vaccinate their offspring tenaciously hold onto their right to refuse. Some have noted, in media reports, that despite potential risk to the public, they are doing what is right for their families. But a future rise in the number of measles (or other infectious disease) cases could increase public pressure to vaccinate and might influence non-vaccinators to change their behavior.

Parental Responsibility In The Era Of Risk Awareness

No new parent in the U.S. can avoid information about vaccine safety, risk, and connections with autism. Parents today respond to the idea of that connection—there is no way not to respond—and then live in the relationship to risk and responsibility that it conjures for them. While anti-vaccination sentiment has existed since Jenner discovered how to prevent smallpox in the 1700s, the kind of awareness arising in the late 1980s and early 1990s indicated something different.

Contemporary parents are mostly not anti-vaccination, nor are most of them members of organized vaccine resistance groups. They are aware that autism has a strong genetic component. They also consider that environmental factors might contribute to expressions of genetic susceptibility or simply trigger disease.

Yet they, and all of us, live in a time of frightening infectious disease epidemics, daily reports of new health risks, and changing scientific truths. The recent reversals about the safety of hormone replacement therapy for instance, the changes in guidelines for cancer screening, and the always emerging dietary guidelines are a few of the many examples of how scientific evidence is not definitive.

For some, no amount of evidence is enough. Anxiety and uncertainty grow despite risk calculation and clinical studies. Importantly, perceptions of risk resist the evidence of experts, especially when shaped by parents’ personal stories of a connection between vaccines and disorder.

When skepticism about expert systems becomes widely pervasive, when it crosses some tipping point in popular understanding, then establishing trust faces an uphill battle, especially for those who begin from the widely held position parents in my study expressed: “Why introduce unnecessary, potentially toxic, potentially contaminating material into a child’s body?” In the realm of vaccine awareness today, trust is not assumed.

All of these developments feed doubt about vaccine safety that has persisted among a large-enough minority of parents to lead to disease outbreaks.

Cautious Parents And The Evaluative Enterprise

Parents of vaccine-age children who live within a relationship to risk, doubt, and competing forms of knowledge forge a flexible ethics. Opportunities abound for “seeing” doubt. An astounding array of means for knowledge production about the possible relationships between vaccines and developmental disorder has emerged in recent years and is taken for granted by parents today.

Together these many means maintain and reinforce doubt. Examples include: websites and discussion groups that connect autism with vaccines simply by expressing concern; states’ personal belief exemption options; the Vaccine Adverse Event Reporting System; books such as What Your Doctor Doesn’t Tell You About Children’s Vaccinations; class-action lawsuits; and physicians who create personalized immunization schedules for concerned parents. All of these are cultural phenomena that parents described to me as creating and sustaining doubt.

New information changes the nature of truth. So, some parents doubt. The moral compass guiding parents who dwell in the midst of both powerlessness and responsibility is their obligation to the wellbeing of their children. That obligation has become, for some, uncoupled from medical expertise.

The Challenge Ahead

The loosening of state exemption requirements for school-age children fed and continues to reinforce the perceived connection between vaccines and disease causation. In fact, the most recently created category of exemption, one based on parents’ personal beliefs, was put in place after the rise of vaccine anxiety, creating a bureaucratic slot for it.

Scientists who chart vaccination trends have suggested that removing or tightening that option as one possible solution to parental refusal. Other researchers suggest that states put administrative rules in place to make it more difficult to obtain exemptions. Eliminating the religious exemption would further protect communities. (All states allow medical exemptions; 19 states allow parents to decline vaccines for personal or philosophical reasons; 48 allow religious exemptions.)

It is possible that variation in state exemption policies undermines, for some parents, the importance of vaccines. Laws that allow the personal exemption are now being debated in California, despite predictions by health officials of a backlash from parents who choose not to vaccinate for personal reasons.

Policy makers would be wise to realize that doubt and distrust of expert systems are widely shared cultural facts in our contemporary “risk society,” and insisting that childhood vaccines are safe will only go so far. Dislodging the fear of vaccines will require coupling greater knowledge of the causes of neurodevelopmental disorder with fewer available means for the maintenance of doubt.

More stringent exemption policies would most likely lead to increased vaccination. A consistent approach within the medical community regarding personalized immunization schedules might help increase parental acceptance of the norm also. Personalized vaccine schedules for parents wary of certain shots or “too many” shots represent an attempt by clinicians to ensure that children have at least some disease protection, but this uneven practice also feeds doubt about vaccine safety. Physicians should be aware of this, and continue to allow time to address parental concerns.

Parents’ ethical judgments, like all of ours, are firmly grounded in the constellation of socio-cultural phenomena that characterize our times and inform our lives.