Here we go again. And again. And again. A bad measles outbreak is currently hitting the area just north of Portland, Oregon, with 23 cases and a public health emergency declared. Another in Brooklyn (55 cases) has spread up the lower Hudson Valley north of New York City (116 cases). One just popped up in Atlanta. There were 17 other outbreaks (defined as three or more cases) across the United States last year. And things are far worse in Europe: 41,000 cases in the first six months of last year, including at least 37 deaths.
Just as predictably, along with each of these outbreaks has come the frustration from multiple sources that these illnesses, and the massive costs they impose on communities trying to rein things in, could have been avoided if only people vaccinated their children against this disease. Article after article decries the problem, explaining the safety of measles vaccination and terms like herd immunity. Rational appeals are peppered with scolding charges of “irrationality,” “science denial,” and “madness.” Appeals to reason and evidence seem logical, but the appeals themselves are also unreasonable in their own way: They deny what these continuing episodes should make clear to us—that reason and evidence alone are not what this is all about.