Those numbers are from CDC planned scenarios for outbreak or some shit like that.
https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scenarios.html
The parameters in the scenarios:
- Are estimates intended to support public health preparedness and planning.
- Are not predictions of the expected effects of COVID-19.
- Do not reflect the impact of any behavioral changes, social distancing, or other interventions.
https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scenarios.html
The parameters in the scenarios:
- Are estimates intended to support public health preparedness and planning.
- Are not predictions of the expected effects of COVID-19.
- Do not reflect the impact of any behavioral changes, social distancing, or other interventions.