It’s on the CDC site but

Low Transmission: <10 per 100k cases in the past week and <5% positive test results in the past week
Moderate: 10-49 cases per 100k or 5-7.99% positive
Substantial: 50-99 cases per 100k or 8-9.99% positive
High: >100 cases per 100k or >10% positivity

Replies:

Where did they get those numbers? - mintirish 2021-08-02 13:20:28
- "percent of hospitalizations to cases has gone way down - ufl 2021-08-02 14:27:31
  - Thanks for posting the data - mintirish 2021-08-02 14:55:57
  - On your part b question - OrangeJubilee 2021-08-02 14:38:02
    - I certainly expect (hope) that this will work with deaths - ufl 2021-08-02 14:43:01
      - It is evident in the UK data, but not in the Florida data - Father Nieuwland 2021-08-02 14:56:24
        Also evident in the NL data - ndhouston 2021-08-02 15:36:30
        I expect a smart quant guy will probably construct a formula - Father Nieuwland 2021-08-02 15:42:03
        You'll need to account for vax distribution as well - ndhouston 2021-08-02 15:49:27
        Where may one find U.K. hospitalization data over time? * - ufl 2021-08-02 15:11:33
        . (link) - Father Nieuwland 2021-08-02 15:15:47
        Thanks * - ufl 2021-08-02 15:18:59
      - Yeah it's all supposition right now - OrangeJubilee 2021-08-02 14:56:16
        Testing is way down - mintirish 2021-08-02 14:58:35
- Hospitalizations are a lagging indicator. - ndroman21 2021-08-02 14:03:12
  - As I said - but you can't use last year's case numbers - mintirish 2021-08-02 14:10:22
    - Do we have data on Delta in a partially vax'd populace? - ndroman21 2021-08-02 14:29:47
- We used those numbers as well. - ewillND 2021-08-02 13:46:35
- Probably via a committee of public health experts - vermin05 2021-08-02 13:33:16
  - They are not new - mintirish 2021-08-02 14:12:02
    - Since the vast majority of cases are amongst the unvax'd.... - ndroman21 2021-08-02 14:31:51
      - but we are talking about vaccinated people wearing masks - mintirish 2021-08-02 14:53:55