Comparison of influenza viral load in nasopharyngeal and midturbinate swabs

Influenza Other Respir Viruses. 2024 Jan 21;18(1):e13253. doi: 10.1111/irv.13253. eCollection 2024 Jan.

Abstract

Different specimen types are used for influenza diagnosis but comparative data for viral loads from different swab types are limited. We compared influenza viral loads (determined by quantitative reverse transcription polymerase chain reaction [RT-PCR]) in 93 paired midturbinate and nasopharyngeal swab aliquots from influenza infected patients enrolled in a phase 3 randomized-controlled study with the objective of maximizing the number of swabs available for sequence analysis. Midturbinate swabs yielded a 53% lower viral load versus nasopharyngeal swabs, and this difference was similar for influenza A and B. These data suggest that nasopharyngeal swabs might be preferred in diagnostic settings when obtaining higher viral load is important.

Keywords: CENTERSTONE; influenza virus; midturbinate swab; nasopharyngeal swab; specimen type; viral load.

Publication types

  • Randomized Controlled Trial
  • Clinical Trial, Phase III

MeSH terms

  • Humans
  • Influenza, Human* / diagnosis
  • Nasopharynx
  • Serologic Tests
  • Viral Load