A local doctor believes more accurate scanners will eventually be developed.

PITTSBURGH (KDKA) — A new warning from the FDA about temperature scanners used to screen for coronavirus.

The devices are used at schools, workplaces and places with large crowds to screen for COVID-19.

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But now comes a warning from the FDA that these scanners, which were rushed onto the market with emergency approval by the FDA, are not always accurate.

Until now, the scanners were considered the best way to quickly screen crowds for the virus. But now the FDA is saying it has learned the scanners don’t always work and even if they do, it does not mean you have COVID-19.

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Allegheny Health Network’s Dr. Brian Lamb says many people can have coronavirus but not have a fever. Conversely, if you have a fever, that does not mean you have coronavirus.

“Unfortunately, what they’ve shown is that these really aren’t that accurate,” Dr. Lamb said. “So if you are looking at a large group of people, you are really not targeting in on people who have fevers. You can miss a lot of people.

Dr. Lamb says the most accurate way to detect coronavirus is through individual screening, so you can ask about other symptoms or whether you’ve been exposed to someone who is infected.

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That said, Dr. Lamb believes more accurate scanners will eventually be developed.