According to the team, Crosby is experiencing mild symptoms while Dumoulin is currently asymptomatic.
The Penguins have not played since Saturday’s loss to the Devils. They host the Flyers Thursday night at PPG Paints Arena.
Crosby made his season debut against New Jersey after missing seven games following offseason wrist surgery.
“I’m sure he’s discouraged,” Sullivan said after Wednesday’s practice. “He worked extremely hard to get to this point, and we were all so excited about getting him back in the fold. This puts another road block in front of it. But we’ll control what we can, and we’re hopeful that Sid will return soon.”
Defenseman Kris Letang returned to the team on Monday after 10 days in isolation following a positive diagnosis. Fellow blue liners Chad Ruhwedel and Marcus Pettersson entered into the NHL’s COVID-19 protocol on Sunday.
Players who test positive must be remain isolated for 10 days. Players who are vaccinated can return earlier if they are symptomatic and produce two negative tests on consecutive days.
“I don’t think it’s because guys aren’t diligent, or aren’t doing the right thing,” Sullivan said earlier this week. “I just think this is part of the world we’re living in right now. It’s a little bit different this year, because there’s some semblance of normalcy.
“The protocols aren’t mandated. But I think our guys do a really good job in just using common sense.”