Shayanne Gal/Business Insider
The severity of COVID-19 cases is a spectrum. Cases are categorized as "asymptomatic," "mild," "severe," or "critical." "Mild" is something of a misnomer, though, because it clinically refers to patients who don't need to be hospitalized.
Patients with severe cases are more likely to have shortness of breath, difficulty breathing, and fluid in their lungs. Usually, they'll require care from a medical professional. (Mild cases can develop into severe cases if infections worsen.)
Critical cases will need medical care from a hospital, often in the Intensive Care Unit. These patients can exhibit respiratory failure, septic shock, and organ failure. And of course some people don't seem to exhibit any symptoms.
COVID-19 patients might experience different symptoms as well. Fever presents in 99% of COVID-19 patients, according to a study of nearly 140 patients at the Zhongnan Hospital of Wuhan University. So almost all mild cases involve a high temperature.
A cough occurs in between 60 and 80% of COVID-19 patients, arriving in tandem with a fever at the onset of the disease. It's usually a dry cough.