BRUSSELS—The European Union is reviving an alliance formed last year with U.S. tech businesses to fight online political disinformation, now focused on false info about the coronavirus.

The European Fee, the bloc’s executive physique, has renewed a rapid-alert technique it created with Facebook Inc., Alphabet Inc.’s Google, Microsoft Corp., Twitter Inc. and Mozilla Corp. to make certain that actions from disinformation about the novel coronavirus are shared rapidly with EU governments.