"Corbin is on the injured list," manager Craig Counsell told reporters when asked if the right-hander tested positive for COVID-19. "I can't discuss it."
This is another setback for the Brewers, who are also missing outfielders Christian Yelich (back) and Lorenzo Cain (quad).
"We're getting hit with injuries," Counsell said. "There's no reason to get upset about this. We have to deal with it. We're working on getting guys healthy. Not one of these injuries is a long-term thing. We will get these players back."
Despite the injuries, Milwaukee is still in first place in the National League Central at 14-10 and 1.5 games ahead of the second-place St. Louis Cardinals.
Burnes is a primary driving force for that early success, as he has a 1.53 ERA, a league-leading 0.55 WHIP and 49 strikeouts in 29.1 innings. He also hasn't walked a single batter and has helped set the tone for a pitching staff that is fifth in the National League in ERA.
While the right-hander had an ugly 8.82 ERA in 2019, he broke through during the shortened 2020 campaign with a 2.11 ERA and 1.02 WHIP. His early success this year has been more of the same, and he appears primed to anchor Milwaukee's staff for years to come.
The 26-year-old is under team control until 2025.