I feel like a bad board-game nerd, I’d never heard of it either. (Thank you @VictorViper!)
It’s incredibly scary! It’s one of the scariest, most stressful games I’ve ever played. Ghost Stories, Betrayal, Cthulhu, whatever, they have nothing on the “adult fear” of Pandemic.
If she understands that at age 4, you may have a future candidate for the CDC or WHO or MSF on your hands, man. Good luck, dude, perceptive and intuitive kids can be a handful.