The AG2R-Citroen team were down to three riders when Aurelien Paret-Peintre and Mikael Cherel left the race after testing positive for Covid-19.
Frenchmen Paret-Peintre and Cherel take the tally of riders out of the race with COVID-19 to 11 just before Tuesday's 16th stage to Foix as Cofidis said their German rider Max Walscheid has also tested positive for Covid.
AG2R-Citroen were already without Geoffrey Bouchard, also out with Covid, and Ben O'Connor, fourth overall last year who abandoned injured after a week, as well as injured Oliver Naesen.
On Monday, the International Cycling Union (UCI) had said that two riders' tests needed further investigation.
Last year, if two members of a team tested positive for Covid the whole outfit would be sent packing, which is not the case in this edition.
Whether a rider who tests positive can stay in the race is decided following a meeting between race, UCI and team doctors, depending on the rider's viral load.
German Lennard Kaemna, who won a Tour stage two years ago, will not take the start either because of a "persistent cold", his BORA-Hansgrohe team said.