PSG said in a statement that the players -- including Juan Bernat, Sergio Rico and Nathan Bitumazala -- are in isolation and subject to the appropriate health protocols.
- Don't have ESPN? Get instant access
PSG also confirmed that Neymar is around three weeks away from returning to training following an injury. The Ligue 1 leaders play Vannes away from home in the Coupe de France on Monday.
Coach Mauricio Pochettino said he was unsure whether Messi, who is currently in Argentina, would feature in their next league game, at Lyon on Jan. 9.
"Messi has been in regular contact with our medical team, and when he has a negative test, he will travel to France, but we don't know any more than that. I don't know if he will be involved against Lyon.
"Until he gets a negative test in Argentina, he will not be able to travel to France. So it is all down to the test in terms of when he can travel. ... We will assess when he is ready to play."
France reported 219,126 new confirmed COVID-19 cases in a 24-hour period on Saturday, the fourth day in a row that the country has recorded more than 200,000 cases.
The country has joined the United States, India, Brazil, Britain and Russia in having had more than 10 million cases. PSG are top of the Ligue 1 table on 46 points after 19 matches, 13 points above second-place Nice.