Odum (knee) has been ruled out ahead of Sunday's matchup against the Bears, Cam Inman of The San Jose Mercury News reports.
Odum logged a DNP at Thursday's practice after not being listed on the 49ers' injury report Wednesday, so he likely sustained a knee injury during practice. The 31-year-old has recorded 16 total tackles and four passes defended in 12 appearances this season. With Odum sidelined for the first time this season, expect Tashaun Gipson to serve as San Francisco's top backup safety.