Williams, who was also on the list earlier this season as a high-risk close contact of Vance McDonald, will likely miss Sunday's game against the Buffalo Bills. A positive test would put him out for at least 10 days, while a high-risk close contact would put him in isolation for five days.
The Steelers already had to replace one starting inside linebacker with Robert Spillane expected to miss time with a knee injury sustained against the Washington Football Team. He was replacing Devin Bush, who tore his ACL against the Browns in Week 6. Inside linebacker Ulysees Gilbert III is also still on injured reserve with a back injury, though he returned to practice this week and is eligible to come off the list.
Without Spillane and Williams, the Steelers on Sunday will use a combination of Avery Williamson, whom the team acquired via trade just before the deadline, and Marcus Allen, a safety-turned-inside linebacker. The team doesn't have any other healthy true inside linebackers.
Safety Antoine Brooks, a sixth-round draft pick, has taken some reps at inside linebacker on third down alongside Allen.