A couple of manifestations stand out. One is the prevalence of measles in Europe -- especially Britain -- and the U.S. Measles is endemic in the underdeveloped world because of the unavailability of the MMR (measles, mumps and rubella) vaccine.
But in the developed world it's an artifact of the anti-vaccination movement, which has associated the vaccine with autism. That connection, promoted by the discredited British physician Andrew Wakefield and the starlet Jenny McCarthy, has been thoroughly debunked. But its effects live on, as the map shows.
Vaccine panic also plays a role in the shocking incidence in the U.S. of whooping cough, also beatable by a common vaccine. Researchers have pointed to the effect of "non-medical exemptions" from legally required whooping cough immunizations -- those premised on personal beliefs rather than medical reasons -- as a factor in a 2010 outbreak of whooping cough in California.
The lesson of all this is that vaccination is not an individual choice to be made by a parent for his or her own offspring. It's a public health issue, because the diseases contracted by unvaccinated children are a threat to the community. That's what public health is all about, and an overly tolerant approach to non-medical exemptions -- and publicity given to anti-vaccination charlatans like Wakefield and McCarthy by heedless promoters like, sadly, Katie Couric, affect us all.
Carroll, who assembles the relevant papers and documents on the MMR/Autism sophistry here, deserves the last word. "Vaccinate your kids," he writes. "Please."