Guardiola must now await the result of a follow-up PCR test before finding out if he will be able to lead the English champions for Sunday’s trip to Newcastle.
That match is one of just five Premier League games still scheduled to go ahead this weekend due to a series of postponements as a result of rapidly rising case numbers of Covid-19 in Britain.
Guardiola was last seen in public on Wednesday when he represented City at Sergio Aguero’s retirement announcement in Barcelona.
The 50-year-old, whose mother died from the virus last year, has been vocal on the need for his players and people in general to maintain high levels of caution.
“I’m concerned — not because we are going to cancel or break the league but because in society the virus is here and people suffer,” he said earlier this week.
“Some people, staff here, have got it right now and we’ve spoken with the players almost every day and told them to be careful — stay safe, stay healthy, (wear) masks, social distance.”
City head into the weekend’s round of fixtures with a one-point lead over Liverpool at the top of the table.