“One might suppose that the popular prejudice against vaccination had died out by this time,” one writer complains. It sounds like a lament from today, but in fact, it’s from 1875. Anti-vaxxers may seem like a product of our fake-news, health-hysteria modern times, but the fear that propels these skeptics is as old as the vaccine itself. How has modern medicine not shaken generations’ worth of suspicion and fear? We go back to look at two pivotal moments — the birth of the vaccine and a 1905 Supreme Court case — to understand what still motivates the anti-vaxxers of today.