ABC6: Are Rapid COVID-19 Tests Reliable?
After Ohio Gov. Mike DeWine tested positive - and then negative - for COVID-19 last week, many people are asking if the rapid test that showed a positive result is trustworthy.
According to DeWine, the false positive came from a rapid antigen test. So what could lead to a false test? ABC6 reporter Rodney Dunigan went to Joseph Gastaldo, MD, OhioHealth system medical director of infectious diseases to learn more.
"Testing is very complicated," Dr. Gastaldo told ABC6. He said there are at least three factors that could cause a negative test:
- Contamination - "The specimen could be contaminated with someone who has it," said Dr. Gastaldo. "That's why when you get a swab, you have to process the swab and handle the swab in a very discreet way, so the swab is not contaminated."
- Machine - A glitch with the machine that runs the test.
- Cross-Reaction - An antigen test can cross-react with different respiratory viruses, other coronaviruses, and even influenza.
Gov. DeWine was later given a PCR test, which is a more sensitive test, which is more sensitive.
"We actually look for a genetic piece of RNA, a piece of the virus that's unique to the COVID-19 virus," said Dr. Gastaldo.
Physicians suggest patients do their research before being tested, especially when dealing with something as complex as COVID-19.