The 27-year-old had first tested positive for Covid-19 at the end of October and has missed four games for United as a result.
Telles joined up with Brazil’s squad for the international break after producing a negative test and came off the bench in his nation’s 1-0 victory over Venezuela on Friday evening.
But the Brazilian Football Confederation (CBF) has now confirmed that Guilherme Arana has been brought into the squad after Telles tested positive for Covid-19 on Saturday.
The CBF claims that Telles is ‘no longer in a transmissive stage’, while the entire Brazil squad will undergo a second test on Sunday.
But if Telles tests positive again, he will be unable to travel with Brazil’s squad to Uruguay as the country does not allow people who have the virus to enter, even if they are asymptomatic.
United, meanwhile, are already without Luke Shaw after he was rule out for around a month due to a hamstring problem.
Ole Gunnar Solskjaer’s side resume their Premier League campaign next Saturday as they host West Brom at Old Trafford.
United will then face Istanbul Basaksehir in the Champions League on November 24.