CDC says contamination, design flaw at fault for initial COVID-19 test kit failure

The failure of the CDC's first round of COVID-19 testing kits were the result of contamination and a design flaw, said scientists from the agency.

The explanation Wednesday marked the agency's first public statement on the high-profile misstep that occurred during the onset of the pandemic.

In February 2020, the Centers for Disease Control and Prevention sent an inaugural batch of COVID testing kits to public labs across the country. But within days, most of the kits failed to meet standard thresholds to verify their efficacy, with many of them returning false-positive results. 

"Those three weeks between when the initial test was rolled out and then failed and before we really had a new test available were a really, really long time," Kelly Wroblewski, director of infectious disease programs at the Association of Public Health Laboratories, told Buzzfeed. 

A report in the journal PLOS One claims the false positives were due to contamination of the test's "N1" component, as well as a design flaw in its "N3" component. 

It remains unclear exactly what caused the contamination. It is, however, generally standard for diagnostic test kits to take months or even plausibly years to design and manufacture, meaning it was not shocking that the rushed initials kits failed.

But in this case, Wroblewski says, it should be publicly understood why and how they failed "for the sake of transparency and perhaps restoring some faith in the agency."

Susan Butler-Wu, a clinical microbiologist in Southern California, told The New York Times, "It's something that should have been caught in the design phase."

Further investigation suggests that that contamination pattern of the kits indicates that the agency violated standard medical manufacturing protocols.