By Cheryl Fiandaca

BOSTON (CBS) – A Carlisle man tells WBZ he thought a negative rapid 15-minute Covid-19 test was all he needed to avoid quarantine after vacation. But he was not all set.

While the FDA said positive results with rapid tests are accurate, negative rapid tests may not be.

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“A negative isn’t always a negative,” said Kyle Koeppler, who works in lab testing and diagnostics at World Back to Work. “If it is a negative test you should immediately get tested with a higher sensitivity PCR-based test to confirm that it’s really a negative test.”

But some say people who get the rapid test have no idea that they need a second test.

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“How many people are walking around having taken the rapid test that came out negative and they’re feeling confident that they are in fact negative, when apparently the state doesn’t think you’re really negative until you take another test,” the Carlisle man said. “It’s all pretty confusing and the test cost me $160.”

On the website and on the testing providers’ websites, it does say negative rapid tests do require another test.

As for that second confirmation test, getting those results can sometime take days. Koeppler said the results need to be communicated within 48 hours. “If you start to extend beyond that the results can almost be meaningless,” Koeppler said. “Because if you were positive, then you could have possibly infected so many more individuals.”

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Before you get a Covid-19 test be sure you are getting the one you need and before you pay for testing, check to see if your community is offering free tests.

Cheryl Fiandaca