Nine people, including seven players, have tested positive in the second round of Premiership Rugby's coronavirus screening programme.
A total of 856 players and staff from across the 12 Premiership clubs were tested on Monday.
Last week there were 10 positive results, including six players.
Those who have tested positive, along with their "close contacts", will now isolate in line with government guidelines.
Premiership Rugby plans to resume the current season on 14 August, with nine rounds of the regular campaign left to play.
The first four rounds of fixtures for the resumption were announced on Friday.