Why eye protection might be a necessary precaution against COVID-19

As evidence mounts that the virus that causes COVID-19 can be transmitted through your eyes, researchers suggest that people in high-risk categories should wear eye protection, in addition to practicing social distancing and wearing a mask.

People in high-risk categories, as indicated by the Centers for Disease Control and Prevention, include older adults and people of any age who have serious underlying medical conditions, in addition to frontline workers.

The CDC has not issued formal guidance to the general public for eye protection wear, only for health care workers.

The agency website says that people should wear eye protection in "areas with moderate to substantial community transmission" but that in areas with little to no community transmission "eye protection is considered optional, unless otherwise indicated as part of standard precautions."

When it comes to coronavirus transmission through the eyes, it's not just touching your eyes that is potentially dangerous. Research suggests that the virus can also possibly transmit through the eyes, mouth and nose, from direct exposure of a droplet from coughing, sneezing or even yelling.

A recent study published in Lancet reviewed the risk of viral transmission with social distancing, face covering and eye protection. Although not conclusive, this large study suggests that you are three times less likely to get COVID-19 if you wear eye protection.

Specifically, the study shows that face shields, goggles and glasses were associated with a lower risk of infection compared to no eye covering, with a reduction of risk to 6% from 16%.

Hospitals and health care settings have different policies in place to protect individuals from COVID-19 transmission through the eyes, according to Dr. Todd Ellerin, chief of infection prevention at South Shore Health.

"It is my recommendation that for our patients, our universal precautions should include wearing a mask, a face shield, and hand hygiene," he told ABC News.

But what about outside of the hospital, in everyday life?

According to some researchers, it might be a good idea for everyday people to don eye protection in addition to a mask - especially if you have an underlying medical condition or you work in a job with a lot of interface with the public, such as at a grocery store.

"We know from feline and mouse models of other coronaviruses that infection through the eye is possible. However, given the above evidence, wearing eye protection in high-risk situations seems prudent," said Dr. Vincente Diaz, specialist in ocular immunology and infectious diseases and assistant professor of clinical ophthalmology at Yale University School of Medicine.

"If choosing between glasses and contacts, glasses can provide an additional protective barrier. If in a situation where one may come in contact with COVID positive patients, PPE with a shield can provide more protection."

We are still learning about COVID-19, but from what we do know, this highly contagious virus can introduce itself to the body through many entries. If worn, eye protection should be used with the other transmission-mitigating measures, including a face mask, social distancing and basic hand hygiene.

Ayodola Adigun, M.D., is a fellow in child and adolescent psychiatry at Yale University and contributor to the ABC News Medical Unit.