There has been lots of speculation about the eyes being a source of COVID-19 infection. Some of this has come from a report by a virologist news reporter who claimed to have contracted the disease from his eyes on a plane flight. However, upon repeated testing the reporter never even had COVID-19!
On July 30, 2020 Dr. Fauci mentioned in a press conference the possibility of using eye shields to protect against COVID-19. Dr. Fauci said, "You have mucosa in the nose, mucosa in the mouth, but you also have mucosa in the eye," he continued. "Theoretically, you should protect all the mucosal surfaces. So, if you have goggles or an eye shield you should use it." He noted that goggles and eye or face shields are "not universally recommended" at this time, "but if you really want to be complete, you should probably use it if you can."
Luckily the mucosal linings of the eye are quite unique and have many features that make this route of transmission very improbable. There is going to be a bit of “doctor jargon” here, but we will sum it up for you at the end in layman’s terms.
For any mucosal lining to be an entry point for this virus, it needs Angiotensin-Converting Enzyme 2 (ACE2) receptors and TMPRSS2 proteins as portals on the surface of mucosal cells. However, the density of ACE2 receptors on the eye may be at least 50% lower than in other mucosal tissues. In addition to ACE2 and TMPRSS2 receptors, coronaviruses may need heparin sulfate coreceptors on the cell surface to facilitate viral binding. Such receptors have been detected on the eye. However, they lie beneath the ocular surface and are not immediately accessible to the virus. There also are proteins in human tears that can bind the virus, thereby potentially preventing its attachment to the ACE2 receptor. Finally, “The ocular surface may also be protected by the ‘good’ bacteria living there and comprising a unique microenvironment called the ocular microbiome.”
Whew... Now that we are through that, let’s sum it up:
Yes, the eyes have a mucosal lining and, yes, mucosal linings are where this virus attacks the body, but the mucosal lining of the eye is quite unique compared to the other mucosal linings of the body – thus giving it a natural defense mechanism to avoid infection from this bug. The eyes have been listed as a very improbable site of infection.
Dr. Fauci is correct when he says that to have “perfect” protection, eye shields could be used. However, the research shows that even if someone sneezes or coughs directly into your face, it is highly unlikely you will get the virus through your eyes. The choice is yours to make whether to use face shields or goggles. Hopefully this explanation is helpful in making that decision.
The Doctors at Brookside Optometric always appreciate the trust and honor that our patients bestow on us as they allow us to be their doctors and we are committed to help our patients understand this virus and to help them navigate their way through this pandemic.