COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. It can affect the lungs, but it may also involve other body systems.
Common symptoms
Symptoms can include fever, cough, sore throat, congestion, fatigue, headache, body aches, loss of taste or smell, nausea, diarrhea, or shortness of breath.
Why severity varies
Some people have mild illness, while others develop pneumonia, blood clots, worsening chronic disease, or long-lasting symptoms. Risk is higher for older adults and people with certain health conditions.
Breathing trouble, chest pain, confusion, bluish lips, or severe weakness should be treated as urgent.