Vannett didn't participate in practice Wednesday due to a back injury, John Boyle of the Seahawks' official site reports.
Per Bob Condotta of The Seattle Times, Vannett has a history of back problems, so the issue could be an ongoing concern for him and the Seahawks. The team added Tyrone Swoopes to the practice squad as potential insurance at tight end, though Vannett hasn't been ruled out for the Week 6 matchup with the Raiders at this point. After Will Dissly (kneecap) went down with a season-ending injury in Week 4, Vannett stepped in as the Seahawks' clear No. 1 tight end in the Week 5 loss to the Rams, logging 50 of 60 offensive snaps and finishing with three receptions for 43 yards on four targets.