Institute For The Future

What's the Worst that Could Happen?

 

About a month ago, the World Health Organization released a statement condemning groups who claim that the WHO created a sense of fear and hysteria surrounding the H1N1 flu in order to help vaccine manufacturers sell vaccines. And at some level, it's not surprising that people have begun to question the effectiveness of the vaccine: I was vaccinated against H1N1 in January and haven't been sick since then, but that isn't proof, per se, that the vaccine prevented the flu. But perhaps the bigger challenge is that few people in Europe and the United States have lived through an infectious and deadly epidemic, meaning that we don't really know viscerally what we're trying to avoid. A deadly, infectious flu sounds unpleasant, of course, but most of us can't easily imagine how it would feel to know that going into work or stepping onto a bus could be a death sentence.

 

It turns out that thinking about worst case scenarios is critical to how people make choices about whether or not to vaccinate their children, a 2008 study (subscription required) by Laura Senier. And critically, in terms of vaccines, this worst-case scenario building includes considering both the potential side effects of the vaccine as well as the effects of the potential virus:

 

 

 

Of the 20 parents interviewed, 15 expressed bewilderment over the requirement for the chicken pox vaccine, often commenting that they had personally had the disease and suffered no ill consequences. In the words of one mother, “I mean, I went to a big school, every single person had chicken pox and never once was anybody hospitalized. We all had it; I just can’t take seriously the idea that this is that dangerous a disease that we need to mess with it.” Interestingly, three of the five mothers who were not so vehemently opposed to the chicken pox vaccine had experienced the disease in adulthood, when it is much more likely to have serious complications. This suggests that perhaps their own personal experience of a fairly benign childhood disease under potentially more serious circumstances may have colored their understanding of the risks associated with the disease, and thus oriented them more positively toward the perceived benefits of the vaccine....

 

[T]he experience of having survived a disease personally allows them to move from a personal and concrete experience to a more generalized set of understandings and expectations about being sick. These generalized expectations in turn shape their assessment of what should (or need not) be done to prevent serious illness in the future. In this way, personal experience may bias the individual in favor of or in opposition to official pronouncements about risk management.

 

 

 

 

In other words, most of us don't think in terms of statistics; we think in terms of stories. And even when we're trying to conduct rational cost-benefit analyses, our narratives shift our calculations. And this point applies beyond just laypeople.

 

In a recent, very good feature by Karl Taro Greenfeld on Jenny McCarthy and her leadership of the anti-vaccine movement, Greenfeld attributes the recent fear of vaccines to "our era's strained relationship with scientific truth, our tendency to place more faith in psychological truths than scientific ones." He goes on to say that "in McCarthy's world there is scientific truth and there is emotional truth. There is the fact of a mother looking into her son's eyes and knowing something has gone very wrong and the fact of about two dozen studies showing no link between vaccines and autism. There is the truth of the parents and the truth of the doctors."

 

Greenfeld's point by implication, sets up an old distinction between emotion and rationality and suggests, by extension, that at some recent point, we've forgotten how to be rational. And to be clear, I think that the anti-vaccine movement poses a huge threat to public health. But I also think we should stop pretending that there are people out there who can rationally or objectively navigate risk.

 

Toward the end of Senier's study, she describes an exchange between a doctor and patient.

 

 

 

The pediatrician that I currently go to . . . said to me when I joined his practice, “I will do what- ever it takes to get you to vaccinate, but you cannot stay here if you have not vaccinated your child.” He said, “I started my own practice for this reason. I did my residency in Chicago during the measles outbreak, and I had two children die in my arms, and you cannot stay in my practice because I cannot risk that again. And as a physician, either your kid gets a small case of measles or a bad case of measles, and I can’t do anything about it.”

 

 

 

 

Of course, pretty much every expert would agree that the pediatrician is making the right recommendation regarding vaccines. But the doctor's vehemence doesn't appear to stem from vague descriptions of symptoms--or statistics about the tiny chances of side effects, such as seizures, that have genuinely been seen in response to vaccines--but because of a personal experience with the worst case scenario: Watching a kid die needlessly and being helpless to do anything.

 

As we have more information about future risks--not just in domains like health, but, for example, in navigating climate challenges--we should recognize that how we narrate events will fundamentally shift how even experts manage risks.

 

(My thanks to my friend Oslec for pointing me to Senier's study.)