So 80+%, unless quarantined, are asymptomatic and feel healthy enough to go about their normal daily life infecting other people. That's what is different from influenza virus. When young and healthy get flu, at least they are in bed at home, not in contact with the public. I really really hate this Covid-19 virus so much.
If I am understanding the data correctly it is 80% with mild to
moderate illness at the time of diagnosis and not 80% with only mild symptoms able to go about their daily life.
According to Dr. Wu's presentation from the CROI 2020 conference :
At diagnosis: approx. 80% are mild/moderate; 15% severe; 5% critical
Progression: approx. 10 -15% of mild/moderate cases become severe, and approx. 15-20% of severe become critical
An estimated 75% of 'asymptomatic' cases at the time of diagnosis soon progress to disease
Testing my math here.. out of 200,000 patients 80% of patients mild/moderate equals 160,000, 15% of 200,000 equals 30,000 severe leaving 5% or 10,000 critical.
Of those 160,000 mild/moderate 10 - 15% will progress to severe which at the lower 10% is 16,000 more patients with severe illness; 15 - 20% of the 30,000 severe patients progress to critical which now gives us 4,500 critical patients.
total of patients with severe and critical illness at the time of diagnosis and with progression gives us 46,000 patients with severe illness and 14,500 with critical illness. Leaving 139,500 patients with mild/moderate disease suffering from symptoms from a mild cold to serious enough upper respiratory infection to cause fever, fatigue, sore throat for a few to several weeks, not to mention the scarring in their lungs