The Vikings sent Kirk Cousins home from their practice facility on Thursday, after an illness caused the quarterback to miss their early afternoon walk-through.
Coach Kevin O'Connell said the team was still "working through" whether Cousins' illness could be COVID-19. If he were to test positive for the virus, he would have to quarantine for five days under NFL policy.
"We're still in the process of trying to go through all of that, make sure first and foremost, 'What are you feeling? What's going on?'" O'Connell said. "And then go through our in-house process to make sure that if it does end up being [COVID], we're on top of it, and if it's not, there's still some other stuff going around that we want to make sure we're being smart about the other [89] guys, coaches, everything in-house. [Executive player health and performance director] Tyler [Williams] and [head athletic trainer] Uriah [Myrie] and their staff, we've had a lot of dialogue about that so we'll be smart and deal with it day by day."
O'Connell did not say whether the Vikings planned to play their starters in Sunday's preseason opener against the Raiders, though he added Cousins could stay home from the game in Las Vegas if he isn't feeling well. Even if Cousins' health wasn't a question for the preseason opener, it's possible he wouldn't play much.
"I've kind of had a plan in my mind, as far as playing time throughout the preseason for him," O'Connell said. "Obviously getting on the plane and doing all of the travel stuff anyway, regardless of how he currently feels, what will matter is when it's time to get on the plane Saturday and go. That's something smart that we'll be really cognizant of."
If Cousins does not play on Sunday, the Vikings' decision on a starting quarterback would reveal something about their depth chart, where Kellen Mond and Sean Mannion currently share the No. 2 spot. The Vikings have alternated snaps between Mannion and Mond with their second-team offense, and both figure to get plenty of work in the preseason regardless of Cousins' status.