Stafford was put on the list during training camp on Aug. 1 but was reinstated a few days later after further tests revealed a false positive.
Stafford, 32, will miss Sunday’s game against the Minnesota Vikings. Chase Daniel is the backup behind Stafford.
The team isn’t saying whether Stafford tested positive or came into contact with someone who did, citing policy.
The Lions put linebacker Jarrad Davis on COVID reserve Tuesday.
Stafford played every snap in last week’s loss to the Indianapolis Colts, throwing for 336 yards, three touchdowns and an interception. For the season, Stafford has completed 61.4 percent of his passes for 1,916 yards and 13 TDs against five INTs.
Stafford played just eight games last season after suffering a back injury on the final drive of Detroit’s 31-24 loss to Oakland on Nov. 3. Stafford was put on injured reserve on Dec. 17. Stafford had a streak of 136 straight regular-season starts snapped.
–Field Level Media (@FieldLevelMedia)