Wasps have cancelled training this week after an outbreak of Covid-19 placed the Gallagher Premiership final against Exeter in doubt.
Four players and three members of backroom staff have produced positive results during the latest round of coronavirus testing undertaken on Tuesday, threatening the climax to the English season at Twickenham on October 24.
The personnel affected are now self-isolating and, as an additional measure, Wasps have aborted all training sessions until next week in an attempt to stop the disease spreading.
Premiership Rugby has played down the threat to the final, which is still 10 days away, but the next round of testing on Tuesday and the results produced the following morning will be pivotal.
With England playing Italy in the delayed end to the 2020 Six Nations on October 31, there is no space in the calendar to stage a rearranged final and the match would be cancelled.
"The club's medical team were informed of the test results following the latest round of the PCR COVID-19 screening programme," a Wasps statement read.
"All seven, who are in good health overall, are now self-isolating and so are their close contacts.
"They will continue to follow Public Health England and Premiership Rugby guidelines and protocols.
"Everyone at Wasps send their best wishes to the players and staff concerned.
"The Club's COVID-19 contact-tracing, measures and protocols, which remain rigorous, will continue to be adhered to."
The development comes a week after Sale's rearranged final-round fixture against Worcester was cancelled due to an escalation of positive tests that lifted the Sharks' total from 19 to 27.
Wasps' situation is far less severe, but the potential for Covid-19 to spread means they face an anxious wait with the demise of Sale's play-offs hopes an example of how devastating an outbreak can be.
Bristol have escaped any fallout despite visiting the Ricoh Arena as recently as Saturday for the Premiership semi-final.
The Bears produced no positives on Wednesday and, as the tests were completed over 48 hours after their 47-24 defeat at Wasps, their Challenge Cup final against Toulon on Friday goes ahead as planned.
Exeter, who play Racing 92 in the Champions Cup showpiece at Ashton Gate on Saturday, have also been given a clean bill of health.