Close Encounters of the Third Kind ending / spoiler

There is no deadly epidemic. That's a cover up to keep everyone away from the place where the aliens will arrive and communicate. The aliens communicate with humans at Devil's Tower (the reason why Richard Dreyfuss made that big dirt "mountain", his fascination with that shape, etc.). The little kid is reunited with his mom. Richard Dreyfuss boards an alien ship and leaves with them.

Submitted by Replicant