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Health Experts Warn COVID Rapid Tests Are Less Reliable Than PCR

SAN CARLOS (KPIX) -- Health experts are warning that rapid antigen tests may not be detecting the omicron variant as well as past variants and are giving false negatives in people who are infected with COVID-19.

"At this point it's not completely clear what's going on. We have not seen this with the previous variant," said UC Berkeley professor and infectious disease expert Dr. John Swartzberg. "We're seeing the rapid test often take more than a couple of days of illness before it becomes positive and sometimes it just isn't becoming positive for several days. It does suggest that maybe the rapid test is having more of a difficult time detecting omicron than it did with the other variants."

Swartzberg suggests that if someone who has COVID-like symptoms -- including a fever, cough, sore throat or a loss of smell and taste -- receives a negative rapid test result, they should follow it up with a PCR test, which is more reliable.

"Frankly, we should've always been skeptical of negative tests," said Swartzberg.

He added that the Centers for Disease Control and Prevention as well as the Food and Drug Administration are gathering data as to what's going on with rapid tests during the omicron surge and they're trying to figure out why the antigen tests aren't detecting the variant as well as they did with previous variants.

Swartzberg noted that if a rapid test result is positive, whether someone is exhibiting symptoms or not, they likely have COVID and a PCR test is not necessary.

Joanna Sabo wishes rapid tests were more readily available early on in the pandemic because "then maybe it would save more lives."

"My husband passed away from the virus," she said.

She said the news about rapid tests doesn't make her nervous and that she's just grateful they're now at her fingertips instead of having to stand in line for a PCR test.

"It's easier, it's in the convenience of your home, you're not around anybody else," Sabo said.

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