One thing that will never stop surprising me is the degree to which anti-vaccination campaigns have spread their message.  Dozens of different versions, each ignoring a different combination of inconvenient facts about how vaccines work and what illnesses they don’t cause, all circulate around the Internet, ensnaring people of every political persuasion.  I can understand the mistrust of the medical establishment, whose record is far from clean.  I can understand the societal memory loss that has made vaccines seem unnecessary now that smallpox, polio, diphtheria, measles, and mumps epidemics are no longer the stuff of every Westerner’s childhood.  I can understand the Hobbesian choices imposed by the lack of universal healthcare access in the United States.

I have a lot more trouble understanding the confusion about the societal role of vaccines in protecting the unvaccinated, because religions use that principle all the time to police their own.