France's Gabin Villiere and Mohamed Haouas have joined Antoine Dupont in testing positive for Covid-19 and are doubts to face Scotland in Paris on Sunday, 28 February.
France's health minister said on Thursday that anyone testing positive would need to remain out of contact with others for 10 days, up from seven.
All members of the France squad will be tested again on Sunday, when the unbeaten Six Nations leaders will announce a new 31-man training squad for the Scotland game.
The French Rugby Federation (FFR) announced scrum-half Dupont's result on Friday, with those of wing Villiere and prop Haouas revealed a day later.
Head coach Fabien Galthie and assistant William Servat tested positive earlier this week and have been isolating.
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