"I just received word that I am positive for COVID-19," Christie said on Twitter Saturday morning. Christie later tweeted that he checked himself into Morristown Medical Center as a precaution because of his asthma.
Christie, who is also an ABC News political contributor and was part of the news broadcast's debate coverage, said he is receiving medical attention.
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Christie is among those to take part in Trump's debate preparations and now have tested positive for COVID-19.
As of now five out of nine known participants have tested positive: President Donald Trump, campaign manager Bill Stepien, former senior adviser Kellyanne Conway, and counselor Hope Hicks.
"I want to thank all of my friends and colleagues who have reached out to ask how I was feeling in the last day or two," Christie said.
Christie said he will be keeping the "necessary folks apprised" of his condition.
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