The 49ers announced on social media that offensive tackle Trent Williams and wide receivers Brandon Aiyuk and Deebo Samuel were placed on the COVID-19 list. They joined fellow wideout Kendrick Bourne, who was moved to the COVID-19 list earlier in the day as the league and the 49ers conducted additional contact tracing.
Earlier Wednesday, the 49ers closed their team facility after Bourne tested positive for COVID-19. Williams, Aiyuk and Samuel were all deemed close contacts of Bourne, leading to their placement on the reserve/COVID-19 list.
Bourne's agent, Henry Organ, told NFL Network, the Bay Area News Group and NBC Sports Bay Area that his client was the player who first tested positive. Bourne is asymptomatic, but has gone into self-quarantine.
"Our organization has entered the NFL's intensive protocol, and we are working with the league on contact tracing to identify high-risk individuals," the 49ers said in a news release.
The 49ers conducted virtual team meetings Wednesday because of the positive test result and subsequent contact tracing. Despite the outbreak, the teams' Thursday Night Football game -- set for 8:20 p.m. EST on Thursday -- remains scheduled.
"The health and safety of our players, staff and community are the organization's highest priority," the 49ers said. "We will continue to work closely with the NFL and medical professionals and will follow their direction."
Sources told NFL Network on Wednesday that the Packers had no new positive COVID-19 tests from Tuesday after running back A.J. Dillon tested positive the day before.
The Arizona Cardinals also received no new positive COVID-19 tests from Tuesday after two players tested positive during their Week 8 bye.
The Baltimore Ravens added seven defensive players Tuesday to the reserve/COVID-19 list.
According to the outlets, Stafford's last contact with the individual was Monday, meaning he would be eligible to come off the COVID-19 list Sunday and play against the Minnesota Vikings if he has five consecutive days of negative tests.
This is Stafford's second stint on the reserve/COVID-19 list. He recorded a false-positive test in August.