Wasps' participation in Saturday's Premiership final against Exeter at Twickenham is in doubt after three more players tested positive for Covid-19.
Four players and three staff members tested positive last week, meaning the club now has seven players self-isolating who would be unavailable.
A decision on whether or not Wasps can play will be made on Wednesday after another round of testing on Tuesday.
Bristol Bears will replace Wasps should they be unable to fulfil the fixture.
The Bears finished third in the league and lost to Wasps in the semi-finals earlier this month.
In addition to the three extra players who have returned positive results, a further member of staff has also tested positive.
"After consultation with the medical leads at Premiership Rugby, the RFU and Public Health England, the club will continue not to train at this stage," a Wasps statement said.
"The club's Covid-19 contact tracing, measures and protocols, which remain rigorous, will continue to be adhered to.
"Exeter Chiefs and Bristol Bears have been made aware of the situation prior to the public release of this information."
Wasps, who finished second in the Premiership table behind Exeter, lost to Rob Baxter's side in their last appearance in the final in 2017.
The Coventry-based club should have had an extra week's preparation for the match as the Chiefs were playing in the Champions Cup final on Saturday.
But Lee Blackett's men have not trained since the seven positive tests were announced last Wednesday.
Should Bristol replace Wasps it will be the first time they have made the end-of-season final and would see the holders of Europe's two cup competitions play for the domestic title.
BBC rugby union correspondent Chris Jones
Just five days out from the final, and the Premiership showpiece remains in limbo, with a total of seven players at Wasps now testing positive for the virus in the last week.
The squad will have another round of testing on Tuesday, but even if Wasps are cleared to play, their preparation has been badly hit given they will have a number of players unavailable and have yet to resume training for their biggest match in years.
Bristol remain on standby, with this latest news increasing the Bears' chances of being handed an unprecedented reprieve when a decision is made on Wednesday.
Bears put tropical social plans on hold
As Bristol Bears continue to wait in the wings for an announcement on Wasps' participation, their head coach Pat Lam believes everything should be done to ensure Exeter and Wasps contest Saturday's final.
"We absolutely believe Wasps and Exeter should be contesting this final," Lam said shortly after hearing about the four further positive tests.
"Lee (Blackett) has done a superb job, as has Rob (Baxter). On Saturday, it was superb to see what Exeter have done in winning the European Champions Cup.
"We ourselves have been put in a situation where it's not ideal. Everything with Covid in fact is not ideal.
"To be in a situation where even now, we're still waiting for sure if we've played our final match in this season of all seasons, I've got a players' room next door all decked out in tropical and Hawaiian gear where we were supposed to having our socially-distanced party to wrap up the season.
"We were told we were going to get an answer on Monday morning, so we were hoping to have that party in the afternoon, but we'll keep waiting."
Bristol already have plenty to celebrate after their 32-19 European Challenge Cup final win against Toulon on Friday, plus a third-place finish in the Premiership.
"The players have been great throughout all this," added Lam. "Myself included, we were all booked for holidays this week and ready to go.
"We've put them all on hold for now.
"But when we got back from the season restart, there were a lot of things we all signed-up to: Playing midweek games, forfeiting games if teams couldn't fulfil fixtures and the play-off situation too, with teams potentially dropping out and the next highest-finisher stepping in where we are now.
"We were all hoping we wouldn't find ourselves in this situation, but here we are.
"We've got to get tested ourselves as a group on Tuesday and train and then on Wednesday, we'll see where we go from there."
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