Among 146 nasopharyngeal (NP) and oropharyngeal (OP) swab pairs collected ≤7 days since illness onset, CDC real-time RT-PCR SARS-CoV-2 assay diagnostic results were 95.2% concordant. However, NP swab Ct values were lower (indicating more virus) in 66.7% of concordant-positive pairs, suggesting NP swabs may more accurately detect amount of SARS-CoV-2.
Keywords: SARS-CoV-2; coronavirus; cycle threshold values; nasopharyngeal; oropharyngeal; testing.
Published by Oxford University Press for the Infectious Diseases Society of America 2020. This work is written by (a) US Government employee(s) and is in the public domain in the US.