St Mirren has gone into lockdown after seven members of backroom staff tested positive for coronavirus.
The Buddies confirmed the situation earlier and said no players were affected.
It is thought the outbreak is confined to coaching staff.
As a result a planned friendly with St Johnstone, due to take place this Saturday, has been cancelled.
A statement by the SPFL and SFA joint response group has ordered all clubs to return to testing twice a week as they look to avoid the nightmare scenario of another shutdown ahead of the Premiership kick-off on August 1.
The statement said: "The Joint Response Group has been notified that St Mirren Football Club has today returned seven positive tests for Covid-19.
"We immediately contacted the Scottish Government and the office of the Clinical Director for Scotland to relay this information.
"As a consequence, St Mirren’s planned friendly match at home to St Johnstone, scheduled to take place on Saturday 25 July, has been cancelled.
"In light of this and other recent events, the JRG hereby notifies Scottish Premiership clubs that with immediate effect they must revert to twice-weekly testing protocols until further notice."
