Covid, eye problems linked: study

NEW DELHI: Researchers have found an increasing link between Covid-19 infection and eye problems such as dryness, redness and itchy eyes.

While Covid-19 had been primarily a respiratory infection, the ocular system had shown susceptibility to the Sars-CoV-2 virus with numerous symptoms reported across the globe, said the team from the Kiran C Patel College of Osteopathic Medicine, Nova Southeastern University in the US.

Their study, published in the Cureus: Journal of Medical Science, identified conjunctivitis as the most common ocular symptom, with about one in every 10 patients presenting the symptoms associated with Covid-19.

The team also reported more serious complications such as episcleritis – a benign, inflammatory disease that affects the clear tissue that covers the white part of the eyes, and is unrelated to Covid-19 infection; ophthalmoparesis – a weakness or paralysis of any of the extraocular muscles that garner movement of the eye; central retinal artery occlusion – a serious disease of the eye in which the main artery supplying the retina is blocked due to an atherosclerotic plaque.

Some Covid-19 patients also reported suffering cranial nerve palsies, where an individual takes longer than usual to move their eyes. It can also lead to vision loss.

“Quickly isolating and starting treatment can aid in stopping the spread of this novel coronavirus,” said corresponding author Deepesh Khanna from the varsity’s Department of Foundational Sciences.

The study, based on a review of 233 research papers from 2020 to 2024, also revealed that some patients might present with ocular symptoms as the first indication of Covid-19 infection.

This was because ACE2 receptors that were present in the eye acted as entry points for the Sars-CoV-2 virus to infect cells and cause Covid, the team explained.

The ACE2 receptors present in eyes also “allow for easy transmission of the virus into the conjunctiva”.

“As the number of Covid-19 cases with ophthalmic infection continues to rise, further research must be conducted into the specific pathophysiology of ocular manifestations. Physicians should be informed on how to treat these symptoms, should they come into contact with those patients presenting with ophthalmic manifestations of Covid-19,” the researchers wrote in the paper.

While there is no current cure for Covid, the study showed that Pfizer’s Paxlovid (nirmatrelvir/ritonavir) medication “may help treat Covid-19-positive patients with ophthalmic symptoms”.

The medication was approved by the US Food and Drug Administration in December 2021 for patients with mild to moderate Covid who are at risk of worse outcomes.

The medication can halt viral replication and reduce viral load in the body.