Ravens head coach John Harbaugh told reporters that Jackson reported to camp last week and tested negative for five consecutive days before receiving a positive result Tuesday. Unvaccinated players are subject to daily testing, while vaccinated players are required to get tested just once every two weeks.
Jackson, the 2019 NFL Most Valuable Player, has now tested positive for the coronavirus twice in the past eight months. His first positive test result came last Thanksgiving and caused him to miss the Ravens' game against the division rival Pittsburgh Steelers. He was activated from the reserve/COVID-19 list less than two weeks later.
"It's just part of the deal," Harbaugh said after Wednesday's practice. "It's just the way the world is right now."
Harbaugh also announced that running back Gus Edwards tested positive for COVID-19. Although Harbaugh declined to say how long Jackson and Edwards would be out, unvaccinated players are required to self-isolate for at least 10 days.
The Ravens are set to play in their first preseason game of the 2021 campaign in 17 days.
"I trust every man in this building to take care of one another," said Ravens wide receiver Marquise "Hollywood" Brown, who is close friends with Jackson. "When hiccups like this happen, all you can do is rally around that guy. Send our prayers and send our support.
"Hopefully, he'll be back very soon. For me, I'm just trying to take every step to be safe in myself and come play football."
Jackson has guided the Ravens to the postseason in each of his first three NFL seasons. During that span, he has compiled a 30-7 record in the regular season as the team's starter at quarterback.
The 24-year-old Jackson notched 2,757 passing yards with 26 touchdowns and nine interceptions last season. He has rushed for more than 1,000 yards in each of the last two seasons.