How to Cause a Measles Epidemic in 5 Easy Steps

The majority of Americans are clueless about science — how it works, what it tells us. From health to climate change to evolution, your average American has no real idea how empirical evidence is used to make and test hypotheses, nor that it is especially important to pay attention to data when they disagree with your prior beliefs. Our American approach: When data fail to support our beliefs, we summarily reject them. That’s in part because we…

I contend that there is a widespread lack of understanding of the distinction between “knowledge” and “belief.” This may be contributed to by a fairly loose definition of “knowledge” floating around, like this one from Merriam-Webster online: “information, understanding, or skill that you get from experience or education.” Under this definition, anything I come to understand through experience would constitute knowledge — so it’s not really different from belief. But as a philosophy major in college, I learned a more robust definition in my epistemology class: Knowledge comprises justified, true belief. That is: You can’t be said to “know” something unless you also believe it (that’s a psychological feature of knowledge); you also can’t “know” something that isn’t true (although truth is a metaphysical concept); and finally, you must have justification for your belief before you can be said to truly “know” something. The question of what constitutes adequate justification is what occupies philosophers (such as me in my undergraduate days) or, in biomedicine, researchers, epidemiologists and proponents of evidence-based medicine (such as me in my professional life). It’s what science — dispassionately and objectively testing hypotheses through empirical evidence — is all about.

It’s been interesting, though somewhat confusing, to see how “government” has become the least-trusted source of information for many. While I can understand this distrust to some extent (our dysfunctional Congress, the outsize influence of corporate lobbyists, the continual overreach of governmental guidelines), I find it confusing when this spills over to scientific/evidence-based findings of groups such as the National Institutes of Health and the Centers for Disease Control (CDC). Indeed, when the CDC looked at the greatest public health achievements of the 20th century, childhood immunization topped the list, and as this evidence-based report shows, with good reason. But we Americans don’t trust the CDC; we’d rather…

The beautiful thing about the Internet is that it puts the entire world of information at our fingertips. The problem is, separating truth from fiction requires judgment, something it appears few of us have (see item number one, above). So we’ve learned a handy method that saves both time and brainpower: We just listen to (and believe) the information that comports with our world views and reject the rest. Quick and easy — plus, it feels so good! So when America’s favorite doctor bashes vaccines and TV personality Jenny McCarthy tells you that vaccines cause autism, those anti-vaccine parents have all the justification they need. Who cares that the CDC has strong evidence or that the major study that claimed to show that vaccines cause autism was fraudulent? How could you not trust Dr. Oz and Jenny McCarthy over “science”?

There is an inherent conflict between public health and individual liberty, as is well understood by those in the field. Indeed, when teaching my public health epidemiology course, I would joke about how my American Public Health Association and American Civil Liberties Union cards were battling in my wallet — a quip largely meant to underscore that it is possible to care simultaneously about both issues. But in contrast to many other societies, we Americans seem to have come down squarely on the side of individual liberty, even at the expense of our neighbors, including our kids’ friends and classmates. As this whole measles outbreak emerged, I learned with incredulity that almost every state in the U.S. allows parents to opt out of immunizing their children based on religious or personal beliefs. How shameful it is that we allow “personal beliefs” to trump science! It is an undeniable fact that immunizing children provides benefits not only to the child vaccinated but to the entire community, and conversely, that unvaccinated children pose a substantial risk to public health (as the current measles outbreak amply demonstrates). Perhaps we in the scientific community have done a disservice by labeling this feature “herd immunity” — no one wants to be part of a “herd,” I guess. So let’s just call it “community immunity.” Not only does that make a nice rhyme, but it emphasizes that we do, in fact, live in community. (Of course, we’d need to care about others in our community for that really to work, so this “rebranding” won’t do the trick by itself.)