Sale's game at home to Worcester on Sunday is in doubt because of 16 positive Covid-19 tests, putting their Premiership play-off bid in jeopardy.
Sale are currently fourth, ahead of Bristol only on points difference.
There could also be a knock-on effect for Northampton, who played Sale in their previous match, losing 34-14.
Saints could also have players forced to self-isolate under contract tracing protocols which could also put their final match with Gloucester in doubt.
All six fixtures on the final day of the Premiership regular season are scheduled to kick off simultaneously, with the top four teams progressing to the play-offs.
Premiership Rugby is yet to comment on the Sale situation, but has delayed all team selection information until 12:00 BST on Saturday, 3 October.