Ask the expert: How COVID-19 affects the eyes | Keck School of Medicine of USC

Annie Nguyen

Interviewed by Eric Weintraub, with additional expertise contributions by Dr. Brian Toy

Much continues to remain unknown about the constantly evolving coronavirus disease 2019 (COVID-19). However, more information has become available in the past 1.5 years regarding COVID-19’s effects on one of the most sensitive parts of our bodies: the eyes. To provide an update, Dr. Annie Nguyen, MD, assistant professor of clinical ophthalmology and Assistant Director of the Cornea & Refractive Surgery Fellowship at the USC Roski Eye Institute, answers frequently asked questions about whether our eyes are vulnerable to the novel coronavirus.

If COVID-19 droplets land in your eye, are you susceptible to infection?

The evidence of ocular transmission has not been well studied. However, mucous membranes, which line many body cavities and organs including the respiratory tract, are most susceptible to the novel coronavirus and viruses in general. The surface of the eye and inner eyelids are also lined by mucous membrane called the conjunctiva. Therefore, if infected droplets land in your eye, you are possibly susceptible to the infection. Published reports suggest that SARS-CoV-2 can possibly be transmitted by aerosol contact with conjunctiva.

The mode of COVID-19 transmission is still believed to be primarily through respiratory droplets from person-to-person. However, the virus can also live on surfaces up to a few days; therefore, touching an infected surface, then touching your eyes, nose or mouth without washing your hands may lead to infection, but this risk is generally considered to be low.

Can cleaning the eyes with water or over the counter eyedrops decrease the chance of infection?

The ocular surface has its own protective mechanisms, including antimicrobial proteins and natural lubrication. Therefore, routine cleaning or flushing of the eyes with water is not necessary and may actually strip away some of the ocular surface’s natural protective barriers, leading to increased risk of infection.

If your eyes become irritated or red, using over-the-counter artificial tears may help alleviate your symptoms. If symptoms are persistent, you should contact your eye care provider.

Is it true that contact wearers have a higher risk of infection for COVID-19?

With proper hygiene, there is no evidence that wearing contact lenses increases your risk of infection for COVID-19. However, contact lens wearers touch their eyes more often than the average person. If you tend to touch or rub your eyes, it may be best to switch to glasses temporarily, given risk of transmission from rubbing without proper hand hygiene. Also, glasses minimize risk of irritation from contact lens wear and serve as a barrier that forces you to pause before touching your eyes.

Although not that best protection, glasses can also serve as a partial shield from respiratory droplets. If you do continue contact lens wear, make sure you carefully adhere to contact lens hygiene and wash your hands. If you develop redness or irritation, please discontinue contact lens wear, and contact your eye doctor.

Is it true that pink eye is an early sign of COVID-19? What are some others ocular signs and symptoms?

Yes, pinkeye, or conjunctivitis, has been reported to be a possible sign of infection from COVID-19. It is still uncertain exactly what percentage of patients with COVID-19 have ocular manifestations and different sources are reporting different numbers. Although some studies have reported up to one-third of patients hospitalized with COVID-19 had ocular abnormalities, more studies are still needed. Of course, causes of conjunctivitis that are not COVID-19 related continue to persist.

Since the start of the pandemic, besides conjunctivitis, COVID-19 has been reported to be associated with other ocular problems including episcleritis, uveitis, lacrimal gland inflammation, changes to the retina and optic nerve, and issues with ocular motility. Although rare, some of these issues can lead to vision loss.

Can COVID-19 cause temporary or permanent damage to your eyes (perhaps from lack of oxygen)?

If a patient were in respiratory distress long enough, theoretically poor perfusion and oxygen deprivation could lead to possible damage to metabolically active tissues, such as the optic nerve or retina. In this instance, eye damage would be caused by decreased oxygen, rather than the virus itself. Perhaps the most devastating vision-related complication of severe COVID-19 infection is acute stroke affecting the parts of the brain that control vision.

Multisystem inflammatory syndrome in children (MIS-C) due to COVID-19 has been reported which can lead to increased intracranial pressure and vision loss.

Corneal nerve damage has been associated with “long COVID,” debilitating symptoms that persist more than four weeks after recovery from the acute illness.

Does the Delta variant affect the eyes any differently?

The Delta variant has been shown to be more contagious. Overall, the symptoms are similar to those seen with the original coronavirus strain and other variants; however, cough and loss of taste are less common, and fever, runny nose, headache and sore throat are more common. Like other variants of the coronavirus, delta may be able to cause certain eye-related problems, but we are not certain at this time.

Can COVID-19 be transmitted through tear droplets and is this something to worry about?

The potential of transmission through ocular secretions is currently unknown, and it remains unclear how SARS-CoV-2 accumulates in ocular secretions. Transmission through infected ocular tissue or fluid has been controversial. Novel coronavirus has been detected in tear samples in a small number of cases. Given the presence of viral particles, it is, therefore, possible to transmit COVID-19, although the risk is likely low. However, the infectivity or clinical significance is not known, and additional studies are needed at this time.

What precautions should you take if you are on immunosuppressive medications?

Patients who are immunosuppressed may be more vulnerable to COVID-19 infection, so it is important to adhere to physical distancing measures to minimize risk. Please discuss potential modification of your medication regimen with your physician (uveitis specialist or rheumatologist). In most cases of patients who are not ill, the risk of vision loss from uncontrolled eye inflammation is greater than the possible increased risk of acquiring COVID-19.

How do I protect myself from COVID-19?

Over a year and half into the pandemic, there is now more information available on how to protect yourself from COVID-19. Masking, hand-hygiene, and physical distancing remain effective tools to decrease rate of transmission. Above all, vaccination with one of the three currently available COVID-19 vaccines used in the United States — Pfizer, Moderna and Johnson & Johnson—has been shown to significantly reduce your risk of getting COVID-19 and reduce the severity of symptoms if you get a breakthrough infection. As of August 23, 2021, the FDA has granted full approval of the Pfizer vaccine. Please continue to follow evolving recommendations from the CDC and your health care provider.

Dr. Nguyen closed the interview by reminding us that the COVID-19 situation is always evolving and we are learning more about the virus every day. Please contact your primary care physician if you are experiencing symptoms of COVID-19. If you have irritation or pain in the eye or difficulty seeing, please reach out to an eye care provider.

Dr. Nguyen based much of the information from this interview on what she learned in the following sources: