The 34-year-old returned a positive test while with the Chile national team and looks set to miss the upcoming World Cup qualifiers against Argentina and Bolivia as a result.
La Roja sit sixth in the CONMEBOL qualification standings, two points behind fourth-placed Paraguay in the final automatic spot.
Vidal's participation in the Copa America, which kicks off on June 11, will not be in doubt should he recover as expected.
The Football Federation of Chile revealed the midfielder's diagnosis came after he was struck by a bout of tonsillitis.
A statement on the national team's official website said: "The medical staff of the Chilean national team point out that at the request of Arturo Vidal, it is announced that he was diagnosed in the daily preventive examination with positive COVID."