Table 3.

Incubation period and onset of symptoms of SARS-CoV-2. Reprinted with permission from Ref. [28]. Copyright 2021 Copyright Elsevier.

	Clinical Features	Population Experiencing (%)
1 to 3 day(s) Onset of symptoms	Fever generally appears on the first day Cough, sore throat may appear by 3 days	80% of patients get these mild symptoms
4 to 9 days In the lungs	The virus may reach lungs between 3 to 4 days Difficult breathing may start by 4 to 9 days Acute respiratory distress syndrome due to lungs inflammation between 18 to 25 days	14% of those infected experience these severe symptoms
8 to 15 days In the blood	From the lungs, the infection may enter the blood By the end of 1 week, sepsis may develop	5% of those infected need admissions to an intensive care unit