De Laura's positive test was first reported Thursday by the Spokesman-Review.
The news comes a day after WSU announced that men's basketball coach Kyle Smith had tested positive for the coronavirus. It's unclear if the football team has other positive cases or if availability will be affected because of contact-tracing protocols.
With his positive test coming late in the week, de Laura also is in question for next Friday's Apple Cup game against Washington. The standard isolation period for positive cases is 10 days.
In WSU's release announcing Smith's positive case on Wednesday, it said he was not expected to be available to coach in the Cougars' opener, scheduled for Nov. 25.
In two starts, de Laura completed 43 of 72 passes for 548 yards with four touchdowns and an interception.