Six Hull FC players and two members of the Super League club’s coaching staff have tested positive for coronavirus.
They were informed of their positive tests by Public Health England on Tuesday evening, as were Salford Red Devils, who beat Hull last Sunday.
Both teams have cancelled their scheduled training sessions for Wednesday.
Five Hull FC players who were involved in the 54-18 defeat to Salford tested positive, in addition to a sixth who was not in their matchday 17 – while a sixth member of Sunday’s playing squad is having a retest after an inconclusive result.
Those players are now required to quarantine for 10 days, ruling them out of Sunday’s game against Castleford Tigers.
Salford’s routine weekly test results have not yet been received.