The Juventus forward received his positive test result ahead of taking on Sweden in the UEFA Nations League.
He has since been released from the national team setup and is now isolating.
Cristiano “is doing well, without symptoms and in isolation” according to a statement released by the Portuguese Football Federation on Tuesday afternoon.
Juventus are set to face Crotone and Hellas Verona in the next two weeks in Serie A, with their No.7’s involvement now unlikely.
The Portuguese’s positive result sees the total of infected players in Serie A rise to 30.