Curative’s COVID tests have a risk of false negatives, FDA says. LA County stops using them at some sites

The city and county of LA have been using COVID-19 tests from a startup called Curative. The FDA announced last week that Curative’s COVID tests have a risk of false negatives. Now the county is discontinuing the use of them in some places. Mayor Eric Garcetti says the city will stick with them.

KCRW speaks with Dr. Clemens Hong, who oversees COVID-19 testing for LA County with the Department of Health Services, about the decision and why it’s still important for Angelenos to keep getting tested.

“We made the decision to switch from Curative to Fulgent [Genetics] Lab as a precaution after the review of the Curative data that led to the FDA alert. And because we could easily replace the small volume of PCR (polymerase chain reaction) tests we’re doing with Curative with the tests from Fulgent,” Hong says.

This change in tests will not affect a large amount of overall testing. Hong says, “The decision will affect our mobile testing units, of which we have two, going to three, this week. … And the number of tests that we do within those mobile units is under 10% of all the testing we provide countywide.”

Even so, the issue of false negatives are not uncommon. Hong says, “It’s important to remember that no PCR test is perfect, and that all COVID-19 tests have a risk of false negative results, which means that you may test negative when you have COVID-19.”

He adds, “False negatives are more likely to happen early on because there is no reliable way to detect the infection, and that could lead the virus to spread before people have symptoms. … The important thing to remember is that you need to isolate even if [you are] negative.”