The company said that McIntyre, 35, has been placed in quarantine and that more updates will be given as they become available.
McIntyre was scheduled to face Randy Orton on Monday's edition of Raw, which airs weekly at 8 p.m. EST on the USA Network.
The champ is also coming off a surprise challenge by WWE Hall of Famer and living legend Goldberg, who confronted McIntyre at the end of last week's episode of Raw.
Goldberg challenged McIntyre for the WWE Championship at the Royal Rumble pay-per-view event, which takes place on Jan. 31. WWE does not have the marquee match listed for the Royal Rumble on its official website.
McIntyre is a two-time WWE Champion currently in his second title reign. He won the WWE Championship from Orton in November.