Thielen has 67 receptions for 726 yards and 10 touchdowns this season.
"Adam was battling through an injury and showing his toughness by playing against the Rams, but we're not going to have him the rest of the way, so we just have to ask that much more of some of our other receivers and give some younger players a great opportunity to play and put some stuff on tape and show what they can do," quarterback Kirk Cousins said. "I'm excited for that."
Justin Jefferson, the Vikings' Pro Bowl receiver, leads the team in receiving with 1,451 yards and nine touchdowns. Behind Jefferson, Minnesota will turn to K.J. Osborn and tight end Tyler Conklin to fill the void in Thielen's absence.
Cook, who leads the NFC with 1,067 rushing yards this season and had six touchdowns, was placed on the COVID list on Dec. 23.