Presence of SARS-CoV-2 Viral RNA in Aqueous Humor of Asymptomatic Individuals

Am J Ophthalmol. 2021 Oct:230:151-155. doi: 10.1016/j.ajo.2021.05.008. Epub 2021 May 19.

Abstract

Purpose: The purpose of this study was to determine whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is detectable in the aqueous of asymptomatic individuals presenting for ophthalmic surgery.

Design: Prospective cross-sectional study.

Methods: Setting and participants: all patients undergoing anterior segment surgery at an ambulatory surgical center (ASC) belonging to a tertiary academic center in South Florida during a 102-day period between June and September 2020 received nasal swab testing for SARS-CoV-2 and underwent a relevant review of symptoms prior to surgery, with negative results required for both in order to proceed with surgery. Main outcomes and measurements: a small sample of aqueous humor (approximately 0.2 cc) was acquired at the beginning of anterior segment surgery from all participants. Aqueous humor was analyzed for SARS-CoV-2 viral ribonucleic acid (RNA) using real-time reverse transcriptase polymerase chain reaction. Demographic information was acquired from participants for secondary analyses.

Results: A total of 70 samples were acquired. Of those, 39 samples were excluded due to insufficient material or inconclusive results. Of 31 samples that were successfully analyzed, 6 (19.4%) demonstrated detectable SARS-CoV-2 RNA. None of the 6 individuals (0%) with detectable viral RNA in aqueous humor reported symptoms during the year, compared to 2 of 25 individuals (8%) with negative samples (P = 1). Positive samples were distributed throughout the study period, including both the first and the last days of enrollment.

Conclusions: The presence of SARS-CoV-2 viral RNA in aqueous despite negative nasal swab testing confirmed its presence beyond the blood-ocular barrier in asymptomatic individuals and raises the possibility that the virus may persist in immunoprivileged spaces despite an absence of symptoms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aqueous Humor / virology*
  • COVID-19 / diagnosis*
  • COVID-19 / virology
  • COVID-19 Nucleic Acid Testing
  • Cross-Sectional Studies
  • Humans
  • Prospective Studies
  • RNA, Viral / genetics
  • RNA, Viral / isolation & purification*
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • SARS-CoV-2 / genetics
  • SARS-CoV-2 / isolation & purification*

Substances

  • RNA, Viral