Dr. Eric Topol says rapid Covid tests are ‘not perfect’ — here’s how he recommends using them

Dr. Eric Topol told CNBC on Monday that rapid coronavirus tests have limitations that Americans must keep in mind, as demand for quick diagnostic results surges during a wave of omicron variant infections.

“They’re not perfect,” Topol said in an interview with CNBC’s Jim Cramer on “Mad Money.”

The founder and director of the Scripps Research Translational Institute said that because rapid antigen-based Covid tests are not as accurate as PCR tests, it is best to use them frequently to establish confidence in the results.

“We can’t fully rely on testing” during this omicron wave, Topol said, stressing the importance of wearing masks to help reduce virus transmission. “And if we’re going to use rapid tests, they’ve got to be as close proximal to the time of the event as possible, and that would include travel,” he said.

Topol, an expert in genomics and individualized medicine, said so far the data suggests omicron mostly causes mild sickness in people who have received the Covid vaccine, including a booster shot.

“With omicron, there’s a lot of breakthroughs,” Topol said, suggesting it is about “five fold” more than the number of breakthrough infections caused by the delta variant. “Most of them have been reported to be pretty mild so far, so that’s the great news.”

To be sure, Topol said there continues to be uncertainty surrounding the omicron variant, which was first detected last month. “We’re going to see a really large number of new infections … and a fraction of those are going to be not mild,” he said. “They’re going to be severe, and we just don’t know what that fraction is yet.”

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