Much greater testing capacity is capturing mild and asymptomatic disease that would have never been diagnosed in March/April.

This, combined with better treatment protocols, is driving down both Case Fatality Ratio (confirmed positive cases) and Infection Fatality Ratio (actual estimated infections).

CDC’s “best estimate” currently is an IFR of 0.003% for the under-20 demographic, 0.02% for 20-49, 0.5% for 50-69, and 5.4% for 70+ year olds.