"For those who want to criticize me for lack of quarantine, realize that if the rules on testing had been followed to a tee, I would never have been tested and would still be walking around the halls of the Capitol," Paul said in a statement. "The current guidelines would not have called for me to get tested nor quarantined. It was my extra precaution, out of concern for my damaged lung, that led me to get tested."

Paul's office announced on Sunday that he tested positive for the virus and that he was "feeling fine," but some senators and aides are angry at him for not doing more to self-quarantine earlier and for potentially exposing senators to the coronavirus. In the wake of Paul's diagnosis, Sens. Mitt Romney and Mike Lee of Utah self-quarantined on Sunday.

GOP senators told CNN Paul was in the gym with colleagues Sunday morning, and several pointed out how close Paul had sat to others during Senate lunches in recent days. Sen. Jerry Moran of Kansas said he saw Paul in the Senate swimming pool Sunday, according to a source in the GOP lunch.

Paul is the first senator to test positive for the virus. The senator had attended a major black-tie social event in Louisville, Kentucky, two weeks ago where several attendees have subsequently tested positive, including the wife of Louisville Mayor Greg Fischer. His office said he sought to get tested "out of an abundance of caution."

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