The move will sideline the trio for the 49ers' Thursday Night Football matchup against the Green Bay Packers. Samuel was already set to miss the game due to a hamstring injury.
All other tests were negative, but after the team's tracing, it was determined Williams, Aiyuk, and Samuel came in close contact with Bourne, according to NFL Network's Mike Garafolo.
The latest losses at receiver leave San Francisco with very few options at the position for Week 9.
49ers WRs in 2020:
|Brandon Aiyuk||COVID-19 reserve|
|Deebo Samuel||COVID-19 reserve|
|Kendrick Bourne||COVID-19 reserve|
|Jalen Hurd||Out for season (knee)|
|Travis Benjamin||Opted out|
|Richie James||Questionable (ankle)|
|Trent Taylor||Set to play (Last start: 2017)|
Trent Taylor has racked up nine receptions for 77 yards through eight appearances this season.
San Francisco has been one of the NFL's most injury-riddled teams in 2020. After losing multiple star defenders in the first month of the season - including Nick Bosa and Solomon Thomas - the club now may also have to finish the campaign without quarterback Jimmy Garoppolo and tight end George Kittle.
The Packers are dealing with their own coronavirus issues ahead of Week 9 after running back AJ Dillon tested positive Monday. Fellow runner Jamaal Williams and linebacker Kamal Martin were ruled out of Thursday's contest after being placed on the reserve/COVID-19 list.
Despite the concerns, the game remains on schedule, Garafolo adds.