Ethics and Childhood Vaccination Policy in the United States

Kristin S. Hendrix, PhDl Lynne A. Sturm, PhDl Gregory D. Zimet, PhD; Eric M. Meslin, PhD, FCAHS


Am J Public Health. 2016;106(2):273-278. 

In This Article

The Tragedy of the (Herd Immunity) Commons

Some scholars liken the antivaccine movement to a type of "free-rider" problem[22] reminiscent of Hardin's iconic 1968 "Tragedy of the Commons."[23,24] The analogy would work as follows: a population that is appropriately vaccinated against highly infectious diseases is a common good to the very society of which its members are a part. Like Hardin's fields that must be maintained and replenished over time, the failure of which depletes the community resources, so too must a community maintain its immunity to ensure its health and wellness. Maintaining this common good requires that all vaccine-eligible individuals be vaccinated. However, some individuals refuse to vaccinate themselves and their children for nonmedical reasons. Ultimately, as with Hardin's Tragedy of the Commons, as more individuals behave in a manner that fails to consider the common good, there is a detrimental effect on the overall well-being of the group and, therefore, on the well-being of each individual, including those individuals who chose to forgo vaccination. More specifically, in the case of childhood immunizations, the individual interest at stake is the parents' right to refuse immunization for their children, with the refusal oftentimes based on inaccurate information or lack of understanding of the safety and efficacy of vaccines. One may question whether deference to individual parental decisions extends to situations in which the parents' decision is (1) factually baseless and (2) potentially detrimental to the health of both the children and the community.

There is evidence that forgoing vaccination for oneself because others are vaccinated (free-riding) is evident in some adults' vaccine decisions for themselves.[22,25–27] However, published data are mixed or unclear regarding both the effectiveness of communicating to the public the societal benefits of immunization and the prevalence of free-riding among parents deciding about vaccination for their children.[28–31] Some parents do invoke the herd immunity argument as a reason not to vaccinate, suggesting that it is unnecessary that they expose their child to the risk of side-effects from vaccination if everyone else is vaccinated to a level that prevents the spread of illnesses.[32] Parental decision-making about vaccination lends itself to analysis using game theory,[33] which we will not pursue here, except to support the notion suggested by Shim et al. that vaccination decisions are not simply selfish or selfless but may involve complex relationships between these motivations.[34]

This degradation of the community resource of herd immunity is portrayed in stark reality in the recent California measles outbreak. Furthermore, when we consider data documenting geographic clusters of underimmunization around the United States,[35] it becomes clear that some locations have not attained thresholds necessary to stop vaccine-preventable illness outbreaks, putting people—especially unvaccinated young children, the immunocompromised, and the elderly—at increased risk for contracting an illness.