Risk Communication

vacindexDan Kahan has an article in the October 2013, issue of Science,  “A Risky Science Communication
Environment for Vaccines,” with a specific example of the HPV vaccine issues.  Kahan has written a good article and one that may have not pleased several people. It fits together with my post Web 2.0 for Vaccination Decisions. Kahan makes the case for having scientifically based scientific risk communication strategies which is something that Betsch and Reyna et al try to do in “Opportunities and challenges of Web 2.0 for vaccination decisions.”  Kahan may make a bigger case for just not being stupid and ignoring everything we already know about risk communication.  He says quite well although indirectly that vaccination is really not a cultural cognition issue–yet, but we could make it one if we are not careful.


Kahan notes that one recurring source of risk controversy is the dynamic known as “cultural cognition.” Both to avoid dissonance and to protect their ties to others, individuals face a strong psychic pressure to conform their perceptions of risk to those that distinguish their group from competing ones—a bias in reasoning that can actually intensify as the public becomes more science literate. Cultural cognition makes it likely inevitable that people of opposing cultural orientations would react differently to a high-profile campaign to enact legislation mandating vaccination of 11- to 12-year-old girls for a sexually transmitted disease. Yet there was nothing inevitable about the human papilloma (HPV) vaccine being publicly introduced in a manner so likely to generate cultural conflict. Merck, the manufacturer of the HPV vaccine Gardasil, sought approval from the U.S. Food and Drug Administration (FDA) through the agency’s fast-track review process, which is reserved for treatments of serious diseases—in this case, for a female-only vaccine for cervical cancer. After approval, the company sponsored a nationwide lobbying campaign directed at state legislatures to add the vaccine to the schedule of immunizations required for school enrollment. As Kahan notes, these were profit-driven choices, aimed at enabling Merck to establish a dominant market position for Gardasil before GlaxoSmithKline could secure approval for its rival product, Cervarix. If Gardasil had not been fast-tracked, the FDA would have approved both Gardasil and Cervarix for boys and girls only 3 years later. At that point, both vaccines would have become available immediately even without mandates through private insurance and a host of programs designed to assure universal access to childhood vaccines. Had the HPV vaccine taken this path, it would have likely followed the uneventful course that marked introduction of the hepatitis B virus (HBV) vaccine into the U.S. public health system. Hepatitis B, like HPV, is sexually transmitted and causes cancer.   The HBV vaccine, however, was not handled as a mandatory, girls-only shot for a sexually transmitted disease in a nationwide legislative campaign.

Had the process been handled more normally, parents’ first  information on HPV vaccine would not have been from partisan news outlets. Rather, they would have learned about the vaccine from their pediatricians. Parents do trust their pediatricians on the HBV vaccine, which retained coverage of 90% of children during the period when HPV mandates were being debated in state legislatures. The rate for completing the HPV immunization series now stands at an anemic 33% for adolescent girls, and 7% for boys.

As one who desired to be a bureaucrat but usually fell short due the chronic need of my bosses to give special favors, I must say that Kahan’s narrative looks familiar.  There are close calls, but you come out a loser over the long run by trying to say who has the most important problems.  Merck apparently was convincing even though the fast track probably hurt Merck also.  Trying to save women from cervical cancer in the short run likely cost many over the long run.  Undermining a fair but imperfect process with special favors polarizes people into their worst cultural cognition selves.  Then we know that “they” are imposing their wills on “us.”

Kahan writes that there was and remains no process in the FDA or the CDC for making evidence-based assessments of the potential impact of their procedures on the myriad everyday channels through which the public becomes apprised of decision-relevant science.  Evidence-informed risk communication strategies are essential to identify and counteract any influence that could cause ungrounded fears of vaccines to spread to the general population.
Ironically, one such influence is empirically uninformed risk communication. The media and advocacy groups routinely lament a “growing distrust of vaccinations”and a resulting “erosion in immunization rates”, claims belied by CDC statistics according to Kahan. Emphatic assertions that a technology poses no danger can actually enhance its perceived riskiness. In addition, people tend to contribute voluntarily to public goods—such as herd immunity—when they believe that others are doing so but refrain when they perceive widespread free-riding. Thus, misleadingly implying that increasing numbers of parents are fearfully refusing vaccination could create exactly such fear and resistance. Kahan suggests that critics of mandatory vaccination are small in number and their hostility to vaccines is generally unshared by the majority of the population. Positions on evolution and climate change, by contrast, are highly charged symbols for large cultural groups. Kahan concludes that empirically uninformed and counterproductive risk communication is the inevitable by-product of the absence of a systematic, evidence-based alternative.

Betsch et al look the particular media that is the internet.  They look at three actors in Web 2.0:  The person trying to make a decision–the user–as the receiver of information on the internet; health communicators who try to disseminate facts about vaccination as well as messages supporting recommended vaccinations, and anti-vaccination activists.  Kahan obviously believes that the category of health (or risk) communicators includes many who do not consider themselves as such.  More people have to realize that they are health communicators and act accordingly.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.