Oklahoma Gov. Kevin Stitt has tested positive for COVID-19, becoming the first U.S. governor known to have been infected by the coronavirus.

Stitt, a Republican, disclosed his illness during a press conference over Zoom on Wednesday. He said he had been tested the day before, and that he has been getting tested periodically.

"I feel fine. I felt a little bit achy yesterday, didn't have a fever but just a little bit achy," the governor said. "So just did my regular testing and it came back positive."

Stitt said he's self-quarantining away from his family and that he will be working from home from now.

The governor attended President Trump's rally in Tulsa, held indoors on June 20. Tulsa's health director said that large gatherings including the rally "likely contributed" to the surge in new cases that is currently plaguing the state.

Stitt said the rally happened too long ago for it to have been the site of his infection. "I don't think there was any way it was at the president's rally," he said. "It was too long ago for it to be dormant, based on the science."

Oklahoma Health Commissioner Col. Lance Frye agreed.

"It wasn't that," Frye said. "As far as where he became infected is really unknown. It could be at anytime within the last couple weeks, but it wasn't so far back as the rally."

Stitt has not made any mandate for face coverings in the state. He did not publicly encourage Oklahomans to wear masks until a press conference on June 30, accordingto The Oklahoman newspaper.

"We're not going to mandate [masks] in the state of Oklahoma, and we're not going to be mask-shamers either," Stitt toldreporters last Thursday.

Oklahoma City's mayor has askedpeople to wear masks when indoors in public spaces, and encourages businesses to require them. Tulsa's mayor is seeking an ordinance to require masks be worn in public.

NPR member station KOSU reportsthat Oklahoma saw its largest one-day increase of cases on Wednesday. The number of cases rose by 1,075, nearly a 5% increase in the state's total number. Four people died from COVID-19 in the previous 24 hours, bringing the state's fatality count to 432.

The state is on pace to have more infections in July than it had in total before the month began, KOSU reports.

During his news conference, Stitt encouraged Oklahomans to get tested for the virus. "I want to use my story to remind Oklahomans that if you aren't feeling well, we want you to get tested," he said.

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