Six people connected to three Premier League clubs have tested positive for the novel coronavirus after the first phase of mass testing.
"Players or club staff who have tested positive will now self-isolate for a period of seven days," the league said in a statement.
As many as 748 individuals were screened ahead of a small group training session.
Clubs and individuals have not been disclosed for data protection reasons.
The league will decide early next week when to allow contact training as it looks to restart the season in June.