France scrum-half Antoine Dupont has tested positive for Covid-19, just over a week before the Six Nations meeting with Scotland in Paris.
The French Rugby Federation announced the news on Friday, with 11 other players returning negative results.
All members of the 31-man squad have been tested, with the other results not yet known.
Head coach Fabien Galthie and assistant William Servat tested positive earlier this week and have been isolating.
French health minister Olivier Veran announced on Thursday that anyone testing positive would need to remain out of contact with others for 10 days, up from seven.
A replacement for Dupont has yet to be named, with France recalling tighthead prop Demba Bamba following injury.
The Lyon forward missed the wins over Italy and Ireland with a hamstring problem as Galthie’s team moved top of the table.
Les Bleus, aiming for a first title since 2010, have made two other squad changes, with Toulon duo Jean-Baptiste Gros and Swan Rebbadj also included.
Dorian Aldegheri drops out following Bamba’s return, with Baptiste Pesenti and Hassane Kolingar the others making way.