As LA County switches COVID-19 test provider over possible false negatives, how are other tests different?

Denise Dador Image
Tuesday, January 12, 2021
As LA County switches COVID-19 test provider, how are other tests different?
News that some testing sites in L.A. County will stop using Curative's COVID-19 test due to an FDA warning of possibly inaccurate results is raising questions about how other coronavirus test are different.

When Sandra Wilson and her family were exposed to someone who had COVID-19 in July, they drove to a Curative testing site and swabbed their own throats.

"We were very thankful that even though we had been exposed to a positive-COVID person, that were negative," she said.

Looking back, Wilson believes her test result was correct.

However, news that L.A. County will stop using Curative's COVID-19 test due to an FDA warning of inaccurate results, especially false negatives, concerns her.

"It's very confusing," she said. "And it's very stressful to think that something we thought was pretty accurate might not be any more."

In response to the FDA, Curative said in a statement that their test is being offered under an Emergency Use Authorization.

"The test performance and labeling, however, have not changed, nor has the company observed any changes in test performance," the company said in a statement. "We have been working with the agency to address their concerns and these limitations."

Health officials announced L.A. County will now offer more COVID testing through Fulgent Genetics, which is based in Temple City.

Chief Commercial Officer Brandon Perthuis says the company handles testing in about three dozen local sites and several California counties.

Riverside County to continue using Curative coronavirus test despite concerns over accuracy

Los Angeles County's pop-up testing sites will stop using a COVID-19 test produced by Curative that has been found to have a risk of false negative results.

"The Fulgent test is incredibly sensitive and specific," he said. "We quote a 99% sensitivity and specificity."

The FDA said tests can fail when samples aren't collected correctly. Like Curative, Fulgent also uses a self-collection kit, but Perthuis says how the tests differ are in the lab.

"There's multiple different primer sets and chemistries, and equipment to run this type of test," he said.

At New Year's, Wilson had another exposure. But this time she chose to go with a Fulgent home testing kit that she ordered online.

"We can mail you an RT-PCR collection kit. You collect the sample at home and then mail that back to us," Perthuis said,

He added that companies are being asked to process an unprecedented number of tests. Fulgent is continuing to ramp up its testing capabilities and expand operations.