The Premier League said that six people from three different clubs had tested positive for COVID-19 out of a sample of 748 individuals.
The novel coronavirus tests were taken on Sunday and Monday ahead of the return to small group training.
“Players or club staff who have tested positive will now self-isolate for a period of seven days,” the league said in a statement.
“No specific details as to clubs or individuals will be provided by the League and results will be made public in this way after each round of testing.”
Watford later announced that three people, including one player had tested positive for the virus and all three would self-isolate for seven days in line with Premier League guidelines.
Burnley said that their assistant coach Ian Woan was among those to give a positive result after being tested on Sunday.
“In line with strict Premier League requirements and following a positive test, Ian will now self-isolate for a period of seven days, with a view to being tested again week commencing Monday, May 25,” said Burnley’s statement .
On Monday, the Premier League voted to allow clubs to begin small group, non-contact training with some clubs returning on Tuesday.