The Rio de Janeiro club says the positive results came after tests were conducted on about 250 people.
Three players have already recovered and the others remain separated from the group.
The club says it will begin a series of medical evaluations on squad members.
Atlético Mineiro and Cruzeiro said Sunday one player in each squad tested positive. Atlético said Ecuadorean midfielder Juan Cazares had the virus. Cruzeiro announced that forward Vinícius Popó was infected.
There is still not date set for the return of soccer in Brazil. (AP) APA APA