Test sensitivity is secondary to frequency and turnaround time for COVID-19 screening

Sci Adv. 2021 Jan 1;7(1):eabd5393. doi: 10.1126/sciadv.abd5393. Print 2021 Jan.

Abstract

The COVID-19 pandemic has created a public health crisis. Because SARS-CoV-2 can spread from individuals with presymptomatic, symptomatic, and asymptomatic infections, the reopening of societies and the control of virus spread will be facilitated by robust population screening, for which virus testing will often be central. After infection, individuals undergo a period of incubation during which viral titers are too low to detect, followed by exponential viral growth, leading to peak viral load and infectiousness and ending with declining titers and clearance. Given the pattern of viral load kinetics, we model the effectiveness of repeated population screening considering test sensitivities, frequency, and sample-to-answer reporting time. These results demonstrate that effective screening depends largely on frequency of testing and speed of reporting and is only marginally improved by high test sensitivity. We therefore conclude that screening should prioritize accessibility, frequency, and sample-to-answer time; analytical limits of detection should be secondary.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Asymptomatic Infections
  • COVID-19 / diagnosis*
  • COVID-19 Nucleic Acid Testing*
  • Calibration
  • Computer Simulation
  • Epidemics
  • Humans
  • Kinetics
  • Limit of Detection
  • Mass Screening / methods*
  • Models, Theoretical
  • Polymerase Chain Reaction
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Time Factors
  • Viral Load*