Signs and symptoms in order of prevalence table
|Anosmia (loss of smell)||30-66%|
|Shortness of breath||18.6%|
|Muscle pain or joint pain||14.8%|
|Nausea or vomiting||5.0%|
Symptoms of COVID-19 are non-specific and those infected may either be asymptomatic or develop flu-like symptoms such as fever, cough, fatigue, shortness of breath, or muscle pain. The typical signs and symptoms and their prevalence are shown in the corresponding table. The Centers for Disease Control and Prevention (CDC) lists emergency symptoms including difficulty breathing, persistent chest pain or pressure, sudden confusion, difficulty waking, and bluish face or lips; immediate medical attention is advised if these symptoms are present.
Further development of the disease can lead to severe pneumonia, acute respiratory distress syndrome, sepsis, septic shock and death. Some of those infected may be asymptomatic, returning test results that confirm infection but show no clinical symptoms, so researchers have issued advice that those with close contact to confirmed infected people should be closely monitored and examined to rule out infection. Chinese estimates of the asymptomatic ratio range from few to 44%.
The usual incubation period (the time between infection and symptom onset) ranges from one to 14 days; it is most commonly five days. In one case, it may have had an incubation period of 27 days.