"I tested positive before the holidays," she told her virtual audience. "I'm fine now, everything's good, I'm all clear. I want to thank everyone who reached out with kind words of support."
She said she first learned of her diagnosis just as she was preparing to tape an episode of her long-running show.
"I was getting ready to tape the show and I was in hair and makeup. Then my assistant Craig walks in and says, 'You tested positive for COVID,'" she recalled. "And then everyone around me ran away. I left the studio immediately and our COVID safety team informed everyone that I had been in contact with."
DeGeneres continued: "I went home, obviously, I had to to quarantine. Portia [de Rossi] made me sleep in a different room on a different bed because she wanted the race car bed all to herself. The first three days, I slept for 16 hours a day. And then on the fourth day, I woke up with back spasms. It just persisted and the doctor put me on pain pills and muscle relaxers."
She said the "pain killers did not help" and that it "felt like I cracked a rib." She was then given a steroid pack from doctors, which she said helped ease the discomfort.
"That's the only symptom I had," she said of her back pain. "I didn't have a headache, I didn't have a fever, I didn't lose my sense of taste. I started to feel better and I am very fortunate and very, very blessed. That was it for me."
"The weird thing is I don't know where I got it," DeGeneres added of contracting the virus. "I wear a mask, I wash my hands. It's a mystery to me how that would happen."
On Dec. 31, a spokesperson for Telepictures told PEOPLE that production's initial early January return date had been pushed back by a week due to a spike in COVID-19 cases within Los Angeles County.
The Ellen DeGeneres Show had been filming without an in-studio audience and with a mix of virtual and in-person celebrity guests since season 18 premiered in September.
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