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Saturday, May. 1, 2021

Did the CDC change the laboratory standard for determining a positive coronavirus test result?

Gus Fisher, Gigafact
no

Claims that the Centers for Disease Control has changed its coronavirus testing standards are based erroneously on instructions for labs submitting coronavirus specimens for sequencing in further research. CDC standards for determining whether someone has been infected by the virus haven’t changed.

The CDC is asking labs to screen for specimens with relatively high “viral loads” in order to help study so-called “breakthrough” COVID-19 cases among fully vaccinated people. To determine the load, scientists look at a figure called cycle threshold. Generally, a lower figure indicates a higher viral load, facilitating more accurate and complete examination of the virus.

The relationship between a specific threshold and symptoms and progression of COVID-19 disease are not yet well understood. Higher thresholds continue to be used in general testing for the presence of the virus.

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