Several France players have caught colds, with Raphael Varane and Ibrahima Konate the latest to fall ill and miss training, the French Football Federation has confirmed.
Striker Randal Kolo Muani said the infected were isolating in their rooms.
France face Argentina in the World Cup final at 15:00 GMT on Sunday.
“Those who are sick stay in their rooms,” said Kolo Muani. “They’re being taken care of by the doctors and we’ve been enforcing social distancing. We’re very strict about it.”
Forward Ousmane Dembele agreed, saying the squad “were not scared” of the virus: “We’ve been taking precautions and I think everyone will be ready.”
Boss Didier Deschamps had said on Wednesday he expected Upamecano and Rabiot to be well enough for the final.
However, should Konate and Varane be ruled out, he will have a selection dilemma as he would be without two of his top three defenders.