key: cord-1006472-4jpq611j
authors: Hassan, Muhammad; Mustafa, Fatima; Syed, Fibhaa; Mustafa, Abdullah; Mushtaq, Hafiza Faiza; Khan, Naveed Ullah; Hussain, Nadir; Badshah, Mazhar
title: Ocular Surface: A route for SARS CoV-2 transmission- A Case Report
date: 2021-09-16
journal: Brain Hemorrhages
DOI: 10.1016/j.hest.2021.09.003
sha: 5dee1a7d29919ee89af16fc294a1ac955f069e9c
doc_id: 1006472
cord_uid: 4jpq611j

SARS-CoV-2 infections are transmitted through droplets or through direct contact with secretions from an infected person. The transmission of the virus through tears and other body secretions remains controversial. PCR detection of Covid-19 in the samples/swabs taken from nasopharynx, CSF fluid, and tears, clarifies that the virus may be transmitted through the modes other than aerosol droplets or direct contact. In order to control and prevent this infectious disease, cutting-off the route of transmission will be one of the most important steps. SARS-CoV-2 RNA has been detected in tears and conjunctival samples of patients. The ocular tropism of Covid-19 is still uncertain but contentious.

nasopharynx, CSF fluid, and tears, clarifies that the virus may be transmitted through the modes other than aerosol droplets or direct contact. In order to control and prevent this infectious disease, cutting-off the route of transmission will be one of the most important steps. SARS-CoV-2 RNA has been detected in tears and conjunctival samples of patients. The ocular tropism of Covid-19 is still uncertain but contentious.

Being an epicenter of this catastrophic pandemic, much of the clinical knowledge and experience has been delivered by China to the world. In addition to different factors, the potential of SARS-CoV-2 virus to get transmitted through various routes and modes, would have considerably contributed to the current alarming situation around the globe.

The available data has reported that besides respiratory, cardiovascular, neurologic and GI symptoms, SARS-CoV-2 can even result in ocular manifestations, with the symptoms varying from dry itchy eyes, epiphora, heperemia, chemosis, conjunctivitis or foreign body sensation.

Colavita et al. 1 has reported a case in which the viral replication was observed for over 20 days in the conjunctiva of the infected patient, that advocates the established fact that the survival time of virus can be longer than expected on several surfaces. In such a case, the possibility of a potential site for viral replication and transmission of the eye cannot be ruled out. Ocular surface, being exposed can acquire respiratory droplet infections and can serve as a gateway in their transmission. In a study, a few cases reported conjunctivitis to be the initial presentation of gradually. SARS-CoV-2 RNA was also detected in the tear samples of the same patient and the results were same for the next 28 days (tear samples being taken every alternate day upto 28 th day of illness), after which the SARS-CoV-2 became undetectable. All the strivings and efforts turned out to be fruitful as the patient was discharged successfully on his 28 th day of admission, after he was able to maintain oxygen saturation on room air and all other symptoms were settled. Discussion:

The A study revealed that SARS-CoV-2 was detected in conjunctival specimens of 2 out of 33 (6.0%) and 3 out of 35 (8.5%) in two different studies carried out separately, all the included covid-positive patients had no ocular manifestations. (3, 4) Different methodology and varying definitions of conjunctivitis, timings of sample collection and several other factors may contribute to the varying incidence of ocular manifestations. Also, the few exfoliated cells collected from ocular swabs can make the virus less evident. There is a chance that the RT-PCR kits are lack the sensitivity.

Abrishami M et al. 5 carried out a study in Iran that demonstrated the increased risk of developing chemosis amongst the patients with SARS-CoV-2 in ICU.

The anatomical relationship between ocular and respiratory systems is provided by the nasolacrimal duct, that bridges the two. 6 Beyond this, the cellular receptors e.g. angiotensin converting enzyme-2 (ACE-2) receptors also provide the doorway to all the coronaviruses including SARS-CoV-2 that can bind to it and then get distributed to various issues and cell types, including the conjunctiva. 7 Sun et al. found ACE-2 receptors in cornea and conjunctival tissues. They also found that ACE-2 expression has been found to be located more in the cytoplasm of conjunctiva and corneal cells than on the cell membrane. 8 The potential portal of entry for SARS-CoV-2 to cause an infection could be the eye, also the virus can be shed via ocular secretions and tears. Eyes can harbor the virus and then can act as a carrier.

This can be dangerous transmission mode and thus is of great consideration in order to protect clinicians especially ophthalmologists.

Based on the current evidence and analysis, the potential of SARS-CoV-2 transmission through ocular surfaces exists. Though the risk could be lower than that for respiratory tissues, but not inescapable. In order to curb the spread of SARS-CoV-2, the exact routes of transmission need to be explored further. And for protection and minimizing the transmission, eye protection should be one of the essential safeguards.

SARS-CoV-2 isolation from ocular secretions of a patient with COVID-19 in Italy with prolonged viral RNA detection

The evidence of SARS-CoV-2 infection on ocular surface

SARS-CoV-2 in the ocular surface of COVID-19 patients

Detection of SARS-CoV-2 in ophthalmic secretions

Ocular manifestations of hospitalized patients with COVID-19 in Northeast of Iran

Anatomy and physiology of the nasolacrimal ducts

a pneumonia outbreak associated with a new coronavirus of probable bat origin

Mechanism of the action between the SARS-CoV S240 protein and the ACE2 receptor in eyes