Conjunctivitis, commonly known as pink eye, is an inflammation of the transparent membrane that lines the eyelid and covers the white part of the eyeball. While bacteria, allergens, and other viruses can cause this irritation, SARS-CoV-2, the virus responsible for COVID-19, has been identified as a direct cause of viral conjunctivitis. This ocular manifestation appears in a small percentage of cases, confirming the virus’s ability to affect the eyes. Understanding the nature of this infection and how symptoms should be managed is helpful.
How SARS-CoV-2 Causes Conjunctivitis
The ability of SARS-CoV-2 to infect the eye is directly linked to the presence of specific protein receptors on the surface of ocular cells. The virus primarily uses the Angiotensin-Converting Enzyme 2 (ACE2) receptor to gain entry into human cells throughout the body. Studies confirm that these ACE2 receptors are expressed in the human conjunctiva and the corneal epithelium.
The virus binds to these receptors, initiating a direct viral infection of the ocular tissue. This process is facilitated by a co-factor enzyme called TMPRSS2, which is also present in eye tissues and helps the virus enter the cell. Successful infection of the conjunctival cells triggers the inflammation and irritation characteristic of pink eye. This mechanism shows that ocular symptoms are a direct result of the viral presence, not just a secondary inflammatory response.
Key Symptoms of COVID-Related Conjunctivitis
The pink eye associated with SARS-CoV-2 infection presents similarly to other forms of viral conjunctivitis. The most common sign is redness or congestion of the conjunctiva, making the white part of the eye appear bloodshot or pink. Patients often report an uncomfortable sensation, such as feeling that a foreign object or grit is lodged in the eye.
Excessive tearing and a watery discharge are characteristic features. Unlike bacterial conjunctivitis, which produces a thick, pus-like discharge, the discharge from COVID-related pink eye is usually thin and clear. Some individuals also experience photophobia (increased sensitivity to light) and mild swelling of the eyelids.
These ocular symptoms can emerge at any point during the COVID-19 infection, sometimes appearing alongside systemic symptoms like fever and cough. In rare instances, conjunctivitis has been reported as the very first symptom. It is also possible, though uncommon, for it to be the sole manifestation of the infection, without accompanying respiratory symptoms.
Care and Management of Ocular Symptoms
In most cases, conjunctivitis caused by SARS-CoV-2 is a self-limiting condition, meaning it resolves on its own without needing specific antiviral medication. The duration is similar to other viral types, usually clearing up within one to two weeks. The primary goal of care is to manage discomfort while the body fights the infection.
Supportive home care can significantly relieve symptoms. This includes applying a cool compress to the closed eyelids several times a day. Over-the-counter lubricating eye drops, also known as artificial tears, help soothe irritation and wash away debris, reducing the foreign body sensation. Avoid wearing contact lenses until symptoms have fully resolved.
Strict hygiene practices are necessary to prevent the spread of the virus to others and to avoid infecting the other eye. Individuals should wash their hands thoroughly before and after touching their eyes and avoid sharing towels, bedding, or eye drops. Medical attention should be sought immediately if symptoms include severe pain, a significant change or loss of vision, or if the discharge becomes thick and consistently pus-like, which may indicate a secondary bacterial infection.