Ngwenya, however, says the positive tests will have no bearing on the restart of the campaign, which is scheduled for 8 August.
READ: PSL confirm August 8 restart
"Only three referees tested positive for Covid-19 but are all asymptomatic. We are monitoring them on a daily basis and they are quarantining in the other wing of the hotel," Ngwenya told the Safa website.
Ngwenya said all of the match officials in camp were looking in good shape and will be ready for the league restart.
Meanwhile, Safa has welcomed the decision by the Premier Soccer League (NSL) Board of Governors (BoG) to confirm dates for the conclusion of the 2019/20 season.
"I would like to thank the NSL chairman and the entire Board of Governors for helping put this matter to rest. We will now witness the ultimate and fair conclusion to the current and unique season, and I am sure the football-loving fans can't wait for football to resume again," said Safa president, Dr Danny Jordaan.
Jordaan added that the Covid-19 pandemic had put football to a definitive test but is happy that most of those challenges are now behind us.
"The match officials are getting into peak fitness and come 8 August, it will be all systems go," concluded Jordaan.
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