(NYTIMES) Have you heard that the Covid-19 vaccine turns you into a vampiric monster - and that the proof is right there in the 2007 Will Smith movie I Am Legend? This conspiracy theory appeared online last year and spread so widely that Reuters actually ran a fact check debunking it (and clarifying the plot). One of the screenwriters of the movie also felt compelled to tweet that it was fictional.

While such ludicrous disinformation may seem peculiar to the social media era, it's also a throwback to the origins of the vampire. No, the first vampires did not appear in books or movies. They weren't debonair Transylvanian counts or good-looking, disaffected teenagers. Rooted in folklore, they were symbols of epidemics - and a plausible explanation for disease, at least for the time.