On @ThisWeekABC today I shared some estimates on the number of infectious people in FL. Here are estimates for AZ, CA, GA, TX...

AZ: Cases as of 7/4 (94.6K); cases as of 6/20 (49.8K). Increase of 44.8K over 2 weeks. Assuming case ascertainment of 20%, true number of cases = 220K. Population of AZ = 7.3M, so roughly 3% of population is currently infectious.

CA: Cases as of 7/4 (254.7K); cases as of 6/20 (169.3K). Increase of 85.4K over 2 weeks. Assuming case ascertainment of 20%, true number of cases = 427K. Population of CA = 40M, so roughly 1% of population is currently infectious.

GA: Cases as of 7/4 (93.3K); cases as of 6/20 (63.8K). Increase of 30K over 2 weeks. Assuming case ascertainment of 20%, true number of cases = 150K. Population of GA = 10.6M, so roughly 1.4% of population is currently infectious.

TX: Cases as of 7/4 (191.8K); cases as of 6/20 (107.7K). Increase of 84K over 2 weeks. Assuming case ascertainment of 20%, true number of cases = 416K. Population of TX = 29M, so roughly 1.4% of population is currently infectious.

Masks are important, but not enough. “We conclude that the effectiveness of any one intervention in isolation is likely to be limited, requiring multiple interventions to be combined to have a substantial impact on transmission.” See: https://www.imperial.ac.uk/media/imperial-college/medicine/sph/ide/gida-fellowships/Imperial-College-COVID19-NPI-modelling-16-03-2020.pdf

What are the hundreds of thousands of infectious people in these states doing right now? Isolating? Are their family members quarantining themselves? How many days does it take for them to notify people with whom they have been in close contact? Are they even notifying others?