“Furry fandom,” Wikipedia says, refers to “fictional anthropomorphic animal characters with human personalities and characteristics.” Often, though, it’s just a disgruntled person in a fuzzy suit.

At first glance, it might have looked like a run-of-the-mill social media check-in: "How is everybody doing?" But the message came from Elmo — the furry red friend to kids, Muppets and anyone else.

When Elmo decided to check the emotional pulse of the internet on Monday and ask, “How is everybody doing?” the fiery-colored Muppet couldn’t have anticipated the seismic response he’d receive. Elmo’s ...