France star Kylian Mbappé did not train with his teammates on Tuesday because of a bout of the flu, the team said.
The French players have gathered at Clairefontaine, on the outskirts of Paris, for a training camp ahead of Nations League matches.
France play away against Türkiye on Friday and at Belgium next Monday before hosting Italy on Oct. 2 and Belgium on Oct. 5.
Mbappé, who won the 2018 World Cup with France, remains the team captain under new coach Zinédine Zidane.
This summer, the Real Madrid forward overtook Lionel Messi for the most all-time World Cup goals (22).