Effects of Patient Characteristics on Diagnostic Performance of Self-Collected Samples for SARS-CoV-2 Testing

Emerg Infect Dis. 2021;27(8):2081-2089. doi: 10.3201/eid2708.210667.

Abstract

We evaluated the performance of self-collected anterior nasal swab (ANS) and saliva samples compared with healthcare worker-collected nasopharyngeal swab specimens used to test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used the same PCR diagnostic panel to test all self-collected and healthcare worker-collected samples from participants at a public hospital in Atlanta, Georgia, USA. Among 1,076 participants, 51.9% were men, 57.1% were >50 years of age, 81.2% were Black (non-Hispanic), and 74.9% reported >1 chronic medical condition. In total, 8.0% tested positive for SARS-CoV-2. Compared with nasopharyngeal swab samples, ANS samples had a sensitivity of 59% and saliva samples a sensitivity of 68%. Among participants tested 3-7 days after symptom onset, ANS samples had a sensitivity of 80% and saliva samples a sensitivity of 85%. Sensitivity varied by specimen type and patient characteristics. These findings can help physicians interpret PCR results for SARS-CoV-2.

Keywords: 2019 novel coronavirus disease; COVID-19; Georgia; SARS-CoV-2; United States; anterior nasal; coronavirus disease; coronaviruses; respiratory infections; saliva; self-collected; sensitivity; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged, 80 and over
  • COVID-19 Testing
  • COVID-19*
  • Georgia
  • Humans
  • Male
  • Nasopharynx
  • SARS-CoV-2*
  • Saliva
  • Specimen Handling