With the Texans holding the ball on their own 8-yard line, Schaub faded back into his own end zone and tossed into the left flat where Wilson grabbed it and quickly ran it in for a score 11:15 into the overtime.
The interception ruined a Houston comeback that saw the Texans overcome a 28-7 third-quarter deficit, capped by Schaub's 5-yard TD pass to Andre Johnson and subsequent 2-point conversion with 21 seconds left in regulation to force an extra frame.
Joe Flacco went 22-of-33 passing for 235 yards, two touchdowns and no interceptions for the Ravens (9-4), who stayed one game behind Pittsburgh atop the AFC North.
Derrick Mason hauled down six passes for 78 yards and a pair of scores and Ray Rice chipped in with eight grabs for 66 yards in the win.
Schaub finished 31-of-62 through the air for 393 yards, three TDs and two pick-offs for the Texans (5-8).
Johnson made nine catches for 140 yards and two touchdowns.