Plain English Summary
Background and study aims
COVID-19 is a condition caused by the coronavirus (called SARS-CoV-2) that was first identified in late 2019. This virus can infect the respiratory (breathing) system. Some people do not have symptoms but can carry the virus and pass it on to others. People who have developed the condition may develop a fever and/or a continuous cough among other symptoms. This can develop into pneumonia. Pneumonia is a chest infection where the small air pockets of the lungs, called alveoli, fill with liquid and make it more difficult to breathe.
In 2020, the virus has spread to many countries around the world and neither a vaccine against the virus or specific treatment for COVID-19 has yet been developed. As of March 2020, it is advised that people minimize travel and social contact, and regularly wash their hands to reduce the spread of the virus.
Groups who are at a higher risk from infection with the virus, and therefore of developing COVID-19, include people aged over 70 years, people who have long-term health conditions (such as asthma or diabetes), people who have a weakened immune system and people who are pregnant. People in these groups, and people who might come into contact with them, can reduce this risk by following the up-to-date advice to reduce the spread of the virus.
The possibility that SARS-Cov-2, the virus responsible for COVID-19, can enter at the eye level causing local symptoms and potentially spreading the infection through tears (ocular fluids) has been recently investigated. However, there is no information about the body's response against the virus in the eye.
Who can participate?
COVID-19 patients and non-infected subjects.
What does the study involve?
Tears will be collected for analysis by the Schirmer test (a strip of a non-toxic filter paper is placed within the lower eyelid for 5 minutes to collect tears). Patients will be evaluated for the antibody response against the virus at the blood level (IgG and IgM), and for the presence of ocular and respiratory symptoms, to eventually correlate the analyzed parameters.
What are the possible benefits and risks of participating?
There are no particular risks in participating in the study, as the ocular fluid will be collected by a non-invasive Schirmer test.
Where is the study run from?
University of Ferrara (Italy)
When is the study starting and how long is it expected to run for?
May 2020 to December 2020, or until the planned number of 60 subjects will be reached.
Who is funding the study?
Investigator initiated and funded
Who is the main contact?
Prof. Elisabetta Caselli, email@example.com
Analysis of the anti-SARS-CoV-2 antibody response in ocular fluid of Covid-19 patients: functional meaning and diagnostic/prognostic perspectives
The possibility that SARS-Cov-2, the β-coronavirus causing COVID-19, can affect the eyes causing local symptoms and potentially transmitting and spreading the infection through ocular fluids has been investigated in the past months. The research has mainly focused on detecting the presence of SARS-Cov-2 genome or infectious particles in ocular secretions, to understand whether SARS-Cov-2-positive subjects could spread the virus not only by respiratory droplets but also via ocular fluids. Almost all studies searched virus RNA genome by molecular RT-PCR assays on ocular swabs. Overall, the frequency of SARS-CoV-2 detection in ocular swabs was very low, and the WHO-China Joint Mission on COVID-19 estimated conjunctival congestion in 0.8% of infected individuals, based on a study on 55,924 laboratory-confirmed cases.
However, there is no information about the local immune response against the virus, which could instead be extremely informative of the virus antigen presentation at the eye level.
The present study was thus aimed to evidence the presence of secretory IgA specifically directed against SARS-CoV-2 virus in the ocular fluids.
We expect that the results can give important information on the local immunity developed at the eye level against the SARS-CoV-2 virus.
Such data could be extremely useful for diagnostic/prognostic purposes, and for epidemiological purposes as well.
Approved 04/062020, Comitato Etico di Area Vasta Emilia Centro della Regione Emilia-Romagna (Azienda Ospedaliero – Universitaria di Bologna, Policlinico S.Orsola-Malpighi - Via Albertoni, 15 – 40138, Bologna, Italy; no telephone number provided; firstname.lastname@example.org), ref: 544/2020/Oss/AOUFe
Single-centre observational case-control study
Primary study design
Secondary study design
Patient information sheet
Not available in web format, please use contact details to request a participant information sheet.
COVID-19 (SARS-CoV-2 infection)
The study will recruit symptomatic and asymptomatic COVD-19 patients hospitalized at the University-Hospital in Ferrara (Italy). Control non-infected subjects were enrolled as controls.
The ocular fluids will be collected by Schirmer test.
Each sample will be immediately refrigerated and processed within 1 hour from withdrawal.
Ocular fluids will be examined for:
- the presence and titer of anti-SARS-CoV-2 IgA
- the presence of SARS-CoV-2 RNA genome
- the presence and concentration of pro-inflammatory cytokines associated with the COVID-19 "cytokine storm"
In parallel, patients will be evaluated for the antibody response against the virus at the blood level (IgG and IgM), and for the presence of ocular and respiratory symptoms, to eventually correlate the analyzed parameters.
Primary outcome measure
Presence and titer of anti-SARS-CoV-2 IgA in ocular fluid collected by Schirmer test at a single time point
Secondary outcome measures
1. Presence of SARS-CoV-2 RNA genome in ocular fluid collected by Schirmer test at a single time point
2. Presence and concentration of pro-inflammatory cytokines associated with the COVID-19 "cytokine storm" in ocular fluid collected by Schirmer test at a single time point
3. Antibody response against the virus at the blood level (IgG and IgM) measured by a blood test at a single time point
4. Ocular and respiratory symptoms recorded by the investigator at a single time point
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
COVID-19 patient hospitalized at the University-Hospital of Ferrara (Italy)
Target number of participants
Participant exclusion criteria
Affected by specific ocular pathologies of infectious or other origin
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
University-Hospital of Ferrara
via Aldo Moro, 8
Investigator initiated and funded
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Planned publication in a high-impact peer-review journal.
IPD sharing statement:
All data generated or analysed during this study will be included in the subsequent results publication
Intention to publish date
Participant level data
Basic results (scientific)
- ISRCTN17301812_PROTOCOL (in Italian).pdf uploaded 23/07/2020