Chelsea winger Callum Hudson-Odoi has become the first Premier League player to test positive for coronavirus.
Arsenal manager Mikel Arteta is self-isolating after also testing positive for the virus.
Arsenal’s game against Brighton on Saturday has been postponed but there has been no decision on Aston Villa’s game against Chelsea on the same day.
The Premier League will hold “an emergency club meeting” on Friday to discuss future fixtures.
Chelsea say Hudson-Odoi “displayed symptoms similar to a mild cold on Monday morning” and stayed away from the the training ground.
The club added that the player is “doing well and looking forward to returning to the training ground as soon as it is possible”.
Chelsea’s full squad has gone into isolation.
The Gunners have closed their training ground and club staff who had recent contact with Arteta will also self-isolate.
“This is really disappointing,” said Spaniard Arteta, 37. “I took the test after feeling poorly. I will be at work as soon as I’m allowed.”