Performance characteristics of "lollipop" swabs for the diagnosis of infection with SARS-CoV-2

Diagn Microbiol Infect Dis. 2024 Sep;110(1):116404. doi: 10.1016/j.diagmicrobio.2024.116404. Epub 2024 Jun 16.

Abstract

Background: Common biologic samples used to diagnose COVID-19 include nasopharyngeal, nasal, or oropharyngeal swabs, and salivary samples. The performance characteristics of a sucked "lollipop" swab to detect SARS-CoV-2 virus is assessed in four small sub-studies.

Methods: In each sub-study, a flocked swab was sucked for 20 s and submitted for PCR detection of SARS-CoV-2 virus.

Results: Across all studies, 52 of 69 (75.4%) COVID-19 positive participants had positive "lollipop" swabs. Twelve of the 17 COVID-19 positive participants with negative "lollipop" swabs had known corresponding cycle threshold values of >37 from their nasal/nasopharyngeal swabs, an indication of low viral load at time of sampling. In a paired samples sub-study, the sensitivity and specificity of the "lollipop" swabs were 100% and 98%.

Conclusions: "Lollipop" swabs performed satisfactorily especially in individuals with acute infection of COVID-19. "Lollipop" swabs are a simple method of sample collection for detecting SARS-CoV-2 virus and warrants additional consideration.

Keywords: COVID-19; Non-invasive diagnostics; Viral diagnostics.

MeSH terms

  • Adult
  • Aged
  • COVID-19 Nucleic Acid Testing / methods
  • COVID-19 Testing / methods
  • COVID-19* / diagnosis
  • COVID-19* / virology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nasopharynx* / virology
  • Oropharynx / virology
  • SARS-CoV-2* / genetics
  • SARS-CoV-2* / isolation & purification
  • Sensitivity and Specificity*
  • Specimen Handling* / methods
  • Viral Load / methods