We can compare #COVID19 1% infection fatality rate with an expected >80% attack rate (R0 of ~3) to seasonal influenza with 0.1% IFR and yearly attack rate of ~10%. Simple math would put unmitigated spread as >80X worse than a typical flu season.https://t.co/uLHDQz0Fqq

— Trevor Bedford (@trvrb) April 23, 2020