Field-deployable, rapid diagnostic testing of saliva for SARS-CoV-2

Sci Rep. 2021 Mar 9;11(1):5448. doi: 10.1038/s41598-021-84792-8.

Abstract

To safely re-open economies and prevent future outbreaks, rapid, frequent, point-of-need, SARS-CoV-2 diagnostic testing is necessary. However, existing field-deployable COVID-19 testing methods require the use of uncomfortable swabs and trained providers in PPE, while saliva-based methods must be transported to high complexity laboratories for testing. Here, we report the development and clinical validation of High-Performance Loop-mediated isothermal Amplification (HP-LAMP), a rapid, saliva-based, SARS-CoV-2 test with a limit of detection of 1.4 copies of virus per µl of saliva and a sensitivity and specificity with clinical samples of > 96%, on par with traditional RT-PCR based methods using swabs, but can deliver results using only a single fluid transfer step and simple heat block. Testing of 120 patient samples in 40 pools comprised of 5 patient samples each with either all negative or a single positive patient sample was 100% accurate. Thus, HP-LAMP may enable rapid and accurate results in the field using saliva, without need of a high-complexity laboratory.

Publication types

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

MeSH terms

  • COVID-19 / diagnosis*
  • COVID-19 / virology
  • COVID-19 Nucleic Acid Testing
  • Humans
  • Limit of Detection
  • Molecular Diagnostic Techniques
  • Nasopharynx / virology
  • Nucleic Acid Amplification Techniques
  • RNA, Viral / metabolism
  • SARS-CoV-2 / genetics*
  • SARS-CoV-2 / isolation & purification
  • Saliva / virology*
  • Sensitivity and Specificity
  • Temperature

Substances

  • RNA, Viral

Supplementary concepts

  • LAMP assay