Wasps will be replaced by Bristol in the Premiership final on 24 October if a coronavirus outbreak means they cannot play, says Premiership Rugby.
The Coventry-based club cancelled training after four players and three staff members tested positive.
They are conducting an extra round of testing on Saturday with results expected by Monday afternoon.
If Wasps have to forfeit the Twickenham showpiece, Bristol would replace them as the next highest-ranked side.
Under the league regulations, forfeits during regular season matches result in a 20-0 loss for the side unable to play, as was the case when Sale’s match with Worcester was cancelled.
However, the governing body says a different scenario was approved back in August for the final, a regulation which hands Bristol a lifeline despite their heavy semi-final defeat at the Ricoh Arena.