The Premier League confirmed on Monday that the latest round of Covid-19 tests had produced four new positives.
There were 2,131 players and club staff tested between September 7 and September 13, a Premier League statement said.
The previous week's tests had produced three positives from 1,605 tests. The identity of those testing positive was not announced, but they will now have to self-isolate for 10 days.
The Premier League kicked off at the weekend without fans in stadiums and under strict health protocols owing to the coronavirus pandemic.