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Comparing Objective Conjunctival Hyperemia Grading and the Ocular Surface Disease Index Score in Dry Eye Syndrome During COVID-19
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SARS-CoV-2 on Ocular Surfaces in a Cohort of Patients With COVID-19 From the Lombardy Region, Italy

Claudio Azzolini1, Simone Donati1, Elias Premi1

  • 1Unit of Ophthalmology, Azienda Socio-Sanitaria Territoriale (ASST) dei Sette Laghi, Department of Medicine and Surgery, University of Insubria, Varese, Italy.

JAMA Ophthalmology
|March 4, 2021
PubMed

Insights

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detected in the tears of over half of COVID-19 patients. Conjunctival swabs may serve as a supplementary diagnostic tool for COVID-19.

Area of Science:

  • Ophthalmology
  • Infectious Diseases
  • Virology

Background:

  • Coronavirus disease 2019 (COVID-19) spread globally since February 2020.
  • The role of body fluids in viral transmission is under investigation.
  • Limited data exists on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presence in human tears.

Purpose of the Study:

  • To determine the rate of SARS-CoV-2 in tears of COVID-19 patients.
  • To assess the association between ocular viral presence and clinical conditions.
  • To evaluate the utility of conjunctival swabs for SARS-CoV-2 detection.

Main Methods:

  • A cross-sectional study was conducted in intensive care units in Lombardy, Italy.
  • Conjunctival swabs were collected from 91 hospitalized COVID-19 patients and 17 healthy volunteers.
  • Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) was used for SARS-CoV-2 detection.

Main Results:

  • SARS-CoV-2 was detected on the ocular surface in 57.1% of COVID-19 patients.
  • Viral load in tears varied significantly between patients.
  • A 63% concordance was observed between conjunctival and nasopharyngeal swabs within 2 days.
  • Conjunctival swabs were positive in 10 patients with negative nasopharyngeal swabs.

Conclusions:

  • SARS-CoV-2 RNA is present on the ocular surface of a significant proportion of COVID-19 patients.
  • The infectivity of SARS-CoV-2 in tears requires further investigation.
  • Conjunctival swabs may serve as a valuable supplementary diagnostic test for COVID-19.
Abstract

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