Dr. Joseph Fair, an epidemiologist and virologist, who has been hospitalized with COVID-19 in spite of being in good health and taking precautionary measures, said he believes that he might have contracted the virus through his eyes on a crowded flight.

Dr. Fair, who is the medical consultant for NBC and Today, got sick three days after the flight to his home in New Orleans.

Speaking from his hospital bed, he told TODAY, “I had a mask on, I had gloves on, I did my normal wipes routine … but obviously, you can still get it through your eyes. And, of course, I wasn’t wearing goggles on the flight.”

“That’s one of the three known routes of getting this infection that we just don’t pay a lot of attention to,” he added. “We tend to pay attention to the nose and mouth because that is the most common route. But you know, droplets landing on your eyes are just as infectious.”

Dr. Fair said that the airline had them packed in like “sardines” and that, “instinctively, I probably should have gotten off.” But he did not.

He explained that he had protected his mouth and nose during the flight and had not gone anywhere after the flight but straight to his home. He started feeling sick a few days later.

He suspects that the infection might have invaded his body through the eyes. “It’s the best guess I could give,” he said.

The U.S. Centers for Disease Control and Prevention (CDC) says COVID-19 spreads primarily “from person to person, mainly through respiratory droplets produced when an infected person coughs or sneezes.”

“These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs,” the CDC says. “The virus does not spread easily in other ways.”

However, the agency says, “It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes. This is not thought to be the main way the virus spreads, but we are still learning more about this virus.”

Dr. Fair went on to say, “I think there’s so much we don’t know about it.”

He did not immediately go to the hospital even after having flu-like symptoms and loss of appetite in an attempt not to overwhelm the situation. However, later, he called an ambulance when he could take in only 25% of the oxygen while he was trying to breathe.

Dr. Fair asked to be given oxygen rather than getting intubated. He started responding well to the oxygen and medications within a few days and was no longer in serious condition.

He said he was at the peak of health in his life and had a warning for healthy, younger people who might feel invincible. Dr. Fair, who is a runner, said, “If it can take me down, it can take anybody down.” “You don’t want to have it, that’s all I have to tell you,” Dr. Fair said. “You don’t want to spread it on to anyone that is at any point at high risk, because, you know, looking at me, healthy and exercising and all of that, I can’t imagine being someone with a high-risk condition.”