Christie said he's "Not yet 100%" but that he's at a "fighting 80%" as far as his recovery from the virus goes.
He spent seven days in the intensive care unit where he was given Regeneron and the Eli Lilly antibody treatment. "The doctors decided because I'm an asthmatic they wanted to be very aggressive in the treatment."
The governor went on to say that the coronavirus is "very random, very unpredictable" and that it came on "like a freight train."
"All of a sudden I got a fever, chills, and body aches, and I was wracked with pain and exhaustion," Christie said.
Christie had spent four days with President Trump on the White House grounds preparing for his first debate against former Vice President Joe Biden. He also attended the "superspreader" event following the nomination of Amy Coney Barrett to the Supreme Court.
"It was a mistake," he said. "I was led to believe that all the people I was interacting with at the white house had been tested and it gave you a false sense of security."
Christie told "GMA's" George Stephanopolous that he had been vigilant about mask wearing, social distancing, and hand washing for seven months prior to his diagnosis, but he let his guard down.
"I let my guard down and it was wrong it was just a big mistake," he said. "I was doing it right for 7 months, I let my guard down for a couple of days inside the white house grounds and it cost me in a significant way. I was wrong."
Christie went on to say that he thinks the Trump administration and all public officials should be more affirmative in recommending that the public wear masks.
"There is no downside to you wearing masks, in fact, there's an upside," he said. "We don't know everything we need to know about this disease, but we do know that masks can certainly help."
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Since his diagnosis, President Trump has called his illness as "a blessing from God," arguing it exposed him to promising therapeutics. He has also been an inconsistent advocate for mask wearing, holding large rallies of thousands of people where many of supporters do not follow public health guidance to cover their face to prevent the spread of the virus.
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