CDC Lab Contamination Delayed Coronavirus Testing
CDC Lab Contamination Delayed Coronavirus Testing

CDC Lab Contamination Delayed Coronavirus Testing

Assembling the first COVID-19 test kits in the same room as coronavirus material, along with other practices that didn’t follow protocol, made the tests unusable, officials say.

Ashley Yeager
Ashley Yeager

Ashley started at The Scientist in 2018. Before joining the staff, she worked as a freelance editor and writer, a writer at the Simons Foundation, and a web producer at...

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Apr 20, 2020


The US Centers for Disease Control and Prevention violated its own manufacturing standards, which led to contamination of the country’s first coronavirus tests, rendering them ineffective, The Washington Post reported Saturday (April 18). 

Problems with the tests were reported not long after the first case of COVID-19, the disease caused by SARS-CoV-2, was announced in late January in the US. The Food and Drug Administration (FDA) sent Timothy Stenzel, the agency’s director of in vitro diagnostics and radiological health, to the CDC headquarters in Atlanta to identify the source of the problem.

According to The New York Times, Stenzel found that no one was in charge of the entire test-manufacturing process, and those working on the tests didn’t have much expertise in commercial manufacturing. He also observed several opportunities for contamination, including test kit assembly in the same room with coronavirus material.

The CDC made its test in a lab, rather than in its manufacturing facilities, an FDA spokesperson tells CNN. “CDC did not manufacture its test consistent with its own protocol.”

The part of the test exposed to contamination was not necessary for detecting SARS-CoV-2, the Post reports. Yet, it took several weeks to eliminate that part from the kits, adding to delays in testing across the country. 

Many federal officials, including CDC Director Robert Redfield, have said that contamination in the agency’s labs might have been what made the tests ineffective. A spokesperson for the agency told the Times that contamination was a just possibility, then provided a statement that “C.D.C. implemented enhanced quality control to address the issue and will be assessing the issue moving forward.”

Even with improved tests from the CDC, and now from other commercial companies as well, availability is still limited. Testing is not yet widespread enough to reopen the country, health experts tell the Times.