Premier League clubs recorded 10 positive cases of coronavirus in the latest round of testing.
The confirmed cases came from a total of 1,595 players and staff tested between September 21 and September 27.
It is the highest number of positive results for a single week within the 2020-21 season and an increase of seven from the last week's tests.
The previous highest figure for the season was four, which were recorded between September 7 and 13.
"Players or club staff who have tested positive will self-isolate for a period of 10 days," the Premier League said in a statement.
The latest figures include three at West Ham, which were confirmed by the club last Tuesday.
Manager David Moyes and players Issa Diop and Josh Cullen have all been quarantining following positive tests.