Nerve damage to vocal cords could be the reason why some people recovering from COVID-19 suffer mysterious bouts of shortness of breath for months after shaking off the coronavirus, researchers say. Vocal cords are meant to constrict across the airway while you're talking, vibrating in the air moving past to create the sound of your voice. When you're not talking, the vocal cords retract to allow air to more freely flow into your lungs. But, in some patients, COVID-19 appears to damage the nerve that regulates speech, causing their vocal cords to impede breathing even when they aren't talking, said Dr. Jonathan Aviv, an ear, nose and throat specialist at Mount Sinai Hospital in New York City.