Day: December 24, 2021

Doctors think in terms of how your lungs and other organs are doing and what treatments might be required.

"SARS-CoV-2 is a respiratory virus that causes COVID, and the designations refer largely to how well a patient's lungs are able to oxygenate and what treatment is necessary to keep the illness from progressing," says Stanford University infectious disease physician Dr. Abraar Karan.

"So when we move from mild to severe, we mean how easy or how difficult is it for you to breathe and maintain certain oxygen levels in your blood, and what treatments, if any, should we be using."

Patients, meanwhile, think in terms of how horrible they might feel. This is an important distinction because some patients can have very low oxygen levels without many other symptoms or could have bad symptoms such as high fever and a painful headache but have normal oxygen levels.