COLUMBUS (WCMH) — Gov. Mike DeWine and First Lady Fran DeWine have both tested negative for COVID-19 for the second time.

According to DeWine’s office, both were given a PCR test by the Ohio State University Wexner Medical Center on Saturday.

Saturday’s negative result follows a negative PCR test for both on Thursday.

DeWine tested positive for COVID-19 Thursday after taking a rapid antigen test on his way to meet with President Donald Trump in Cleveland. Later in the day, after taking a PCR test, the results were negative.

The discrepancy between the two test results was explained by Dr. Peter Mohler, chief scientific officer for The Ohio State University Wexner Medical Center and vice dean for research at the OSU College of Medicine, during DeWine’s Friday press conference.

Mohler said PCR tests are what’s been widely used across Ohio throughout the pandemic with roughly 1.6 million PCR tests performed in Ohio.

“This is an incredibly sensitive and incredibly accurate test. It’s like a big telescope way to look at the virus,” Mohler said. “We would call the gold standard the PCT test.”

Mohler said the advantages of the PCR test are that it looks at the genetic makeup of the virus, makes it possible to detect very low viral loads in people that are symptomatic or asymptomatic, and it gives doctors the ability to look at the virus over time, which means doctors are very familiar with the strengths and weaknesses of a PCR tests.

He said the disadvantages of the PCR test are that it’s hard to scale and it takes a certain type of person to be able to run them who’s had the necessary training.

“The antigen test doesn’t look at the genetic material, it looks at the protein on the surface of the virus,” Mohler said. “It’s a little bit less sensitive and so you’re going to have things that we call false negatives and false positives.”

Mohler said the advantage of the antigen test is that it’s possible to have lots of those types of tests across the field and it allows for point of care testing, which means results can come back within 15 or 20 minutes.

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