Sims' placement on the reserve/COVID-19 list Wednesday was the result of a positive test of the virus, Field Yates of ESPN reports.
Washington didn't officially provide an explanation beyond Sims' placement on the list, but Yates notes that 30 of the 31 of NFL players that landed on the list Wednesday tested positive for the virus, with Jordan Ranaan of ESPN.com relaying that Giants safety Xavier McKinney was placed on the list as an unvaccinated high-risk close contact. Because Sims is vaccinated, he'll be eligible to report back to the Football Team facility so long as he's asymptomatic for a 48-hour period and tests negative for the virus on two consecutive occasions at least 24 hours apart. He'll still face an uphill battle to gain clearance for Sunday's game against the Eagles, and at the very least, he won't be able to take part in any of the Football Team's practices this week.