While evaluating data of COVID-19 patients, researchers in China made an interesting observation. They noticed that very few of the hospitalised patients regularly wore glasses.

According to a New York Times report, in one hospital in Suizhou, China, 276 patients were admitted for 47 days. Of these, only 16 patients - less than 6 percent - wore glasses for more than eight hours a day. This was surprising, considering an earlier research had shown that more than 30 percent of similarly aged people in the region needed glasses for nearsightedness.

Eyeglasses may act as a complementary blockade to protect eyes from the droplets released when a person coughs or sneezes. Bespectacled people are also less likely to touch their eyes with contaminated hands.

The study, published in JAMA Ophthalmology, was conducted on a small scale and examined less than 300 cases of COVID-19.

Dr Lisa Maragakis, Infectious Disease Specialist and Associate Professor of Medicine at Johns Hopkins School of Medicine, recommended caution in interpreting the results of the study. Besides the small sample size, another concern is that the data for the comparison group was taken from a study that occurred decades earlier, and therefore is susceptible to bias.

“It’s one study,” Dr. Maragakis said. “It does have some biological plausibility, given that in health care facilities, we use eye protection,” such as face shields or goggles. But healthcare workers require protective gear for their eyes in order to prevent droplets from coughs, sneezes and other such aerosols emanated during medical procedures from entering their eyes. For the vast majority of people, wearing a mask and maintaining physical distance may offer sufficient precaution.

She remarked that any number of factors could have skewed the data. For instance, It might be that those who wear glasses tend to be older in age, which increases their likelihood of staying safely at home during the pandemic. It could also be that persons who can afford glasses have the economic means to take more precautions and avoid crowded places.

There may also be a possibility of increased risk when wearing glasses. Some people tend to touch their faces more often rather than less when wearing glasses, noted Dr Maragakis.

More research is necessary to assess whether this trend is applicable across populations, said Dr Thomas Steinemann, a spokesman for the American Academy of Ophthalmology and Professor of Ophthalmology at MetroHealth Medical Center in Cleveland.

The results of this research also raise questions about eyes acting as the point of entry for the virus. A small percentage of COVID-19 patients are exhibiting eye conditions such as conjunctivitis or pink eye, suggesting that the pathogen may be invading the body through the eyes.

Although eye symptoms for COVID-19 are not as common as other symptoms like fever or cough, a few studies have suggested that eye complaints can also serve as indicators of the infection.

(With inputs from The New York Times)