I wish I could give more of my support to Skeptical Enquirer. It has long been my belief that scientific principals should be applied to incidents of a paranormal nature, so I applaud the magazine/website when it/they do just that, shine the light of Science into the darkness, apply the scientific method to the unexplained and eerie. I say I applaud them WHEN they do it because they don’t always. Far too often, they look at some alleged phenomenon or other, declare it to be impossible and deliver a curt dismissal without any true investigation having taken place. There is a close-mindedness sometimes present, a sometimes smug sense of superiority; “We don’t believe in such foolishness,” the hardline skeptic is wont to say, and “Such things cannot exist!” is used far too often in place of the aforementioned scientific process.
Here’s an example: A man or woman sees a werewolf. Werewolves cannot exist, therefore the man/woman was either hallucinating or is lying. End of investigation. See the problem there? The premature interpretation at play?
Anyway, here’s an interesting page chronicling cases of mass hysteria through the ages. Mass hysteria is used to explain the incident of a cloistered nun in the 1400s who fell to biting her sisters in cloth. Those bitten soon started biting others, and soon enough they had nuns biting each other all over the place. Demonic possession? Lycanthropy? It’s doubtful. This WAS in all likelihood a case of mass hysteria, as was the curious case of the meowing nuns of Medieval France, also mentioned in the piece. Still, we can’t with absolute certainty declare the mystery solved without substantiating evidence, of which there is none. It remains at best a probable scenario, still in need of further investigation.

Maybe ergo in the grain? It would certainly make nuns “meow” and bite.
Possibly.