Performance of Oropharyngeal Swab Testing Compared With Nasopharyngeal Swab Testing for Diagnosis of Coronavirus Disease 2019-United States, January 2020-February 2020

Clin Infect Dis. 2021 Feb 1;72(3):482-485. doi: 10.1093/cid/ciaa759.

Abstract

Among 146 nasopharyngeal (NP) and oropharyngeal (OP) swab pairs collected ≤7 days after illness onset, Real-Time Reverse Transcriptase Polymerase Chain Reaction assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 RT-PCR) diagnostic results were 95.2% concordant. However, NP swab cycle threshold values were lower (indicating more virus) in 66.7% of concordant-positive pairs, suggesting NP swabs may more accurately detect the amount of SARS-CoV-2.

Keywords: SARS-CoV-2; coronavirus; nasopharyngeal; oropharyngeal; testing.

MeSH terms

  • COVID-19*
  • Clinical Laboratory Techniques
  • Diagnostic Tests, Routine
  • Humans
  • Nasopharynx
  • Real-Time Polymerase Chain Reaction
  • SARS-CoV-2
  • United States