Fact Check-CDC lab update on COVID-19 PCR tests misinterpreted

New guidelines from the U.S. Centers for Disease Control and Prevention (CDC) withdrawing their request for Emergency Use Authorization for a coronavirus test introduced in February 2020 do not mean that these polymerase chain reaction (PCR) tests have failed to differentiate between COVID-19 and Influenza, as users online claim. Rather, the agency is advising the adoption of new tests that can check patients for both SARS-CoV-2 and Influenza viruses.

Social media posts, some containing screenshots of a CDC Lab Alert, are claiming that diagnostic tests currently in use in the United States to confirm cases of COVID-19 can’t distinguish between that disease and the flu. One post (here) reads, in part, “The CDC is discontinuing the PCR test it’s been using since Feb 2020 because it can’t differentiate between the flu and COVID-19.”

Other posts (here) show a digitally altered version of the actual guidance from the CDC, visible here .

On July 21, 2021, the CDC Division of Laboratory Systems released a lab alert for those performing COVID-19 testing, saying PCR tests for SARS-CoV-2 should be phased out by the end of the year (“After December 31, 2021, CDC will withdraw the request to the U.S. Food and Drug Administration (FDA) for Emergency Use Authorization (EUA) of the CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel, the assay first introduced in February 2020 for detection of SARS-CoV-2 only”).

This is not due to the tests failing or confusing SARS-CoV-2 with influenza, however, but in order to transition toward using a test that can facilitate the diagnosis of both viruses.

The alert advises labs to switch to other COVID-19 testing methods and “encourages laboratories to consider adoption of a multiplexed method that can facilitate detection and differentiation of SARS-CoV-2 and influenza viruses.” The reason being, “Such assays can facilitate continued testing for both influenza and SARS-CoV-2 and can save both time and resources as we head into influenza season.”

Details about these types of tests can be seen in a fact sheet here .

The statement, “the CDC encourages laboratories to consider adoption of a multiplexed method that can facilitate detection and differentiation of SARS CoV-2 and influenza viruses,” has been stripped of context and misinterpreted by social media users.

CDC spokesperson Jasmine Reed told Reuters via email, “the 2019 Novel Coronavirus (2019 nCoV) Real-Time RT-PCR Diagnostic Panel met an important unmet need when it was developed and deployed and has not demonstrated any performance issues.” Reed continued, “the demand for this test has declined with the emergence of other higher-throughput and multiplexed assays.”

“CDC is encouraging public health laboratories to adopt the CDC Influenza SARS-CoV-2 (Flu SC2) Multiplex Assay to enable continued surveillance for both influenza and SARS-CoV-2, which will save both time and resources,” Reed added.

Fact-checker Health Feedback also tackled this claim, here .


False. The CDC is not removing some PCR tests because they failed to differentiate between COVID-19 and Influenza. The agency says it is opting for multiplex assays (that can test for both viruses) to save time and resources.

This article was produced by the Reuters Fact Check team. Read more about our fact-checking work here .