COVID-19 is the infectious disease caused by the coronavirus, SARS-CoV-2, which is a respiratory pathogen.
The most common symptoms of COVID-19 are: fever, dry cough, fatigue
Other symptoms that are less common and may affect some patients include: loss of taste or smell, nasal congestion, conjunctivitis (also known as red eyes), sore throat, headache, muscle or joint pain, different types of skin rash, nausea or vomiting, diarrhea, chills or dizziness.
Most people (about 80%) recover from the disease without needing hospital treatment. About 20% of those who get COVID-19 become seriously ill and require oxygen, with 5% becoming critically ill and needing intensive care.
Complications leading to death may include respiratory failure, acute respiratory distress syndrome (ARDS), sepsis and septic shock, thromboembolism, and/or multiorgan failure, including injury of the heart, liver or kidneys.
In rare situations, children can develop a severe inflammatory syndrome a few weeks after infection.
In most situations, a molecular test is used to detect SARS-CoV-2 and confirm COVID-19. Polymerase chain reaction (PCR) is the most commonly used molecular test. Samples are collected from the nose and/or throat with a swab. Molecular tests detect virus in the sample by amplifying viral genetic material to detectable levels. For this reason, a molecular test is used to confirm an active infection, usually within a few days of exposure and around the time that symptoms may begin.
Rapid tests (sometimes known as a rapid diagnostic test – RDT) detect viral proteins (known as antigens). Samples are collected from the nose and/or throat with a swab. These tests are cheaper than PCR and will offer results more quickly, although they are generally less accurate.
