Descriptions of pandemic scenarios at the time of initial COVID-19 vaccine availability
| Scenario | Description |
|---|---|
| 1 | The pandemic is still in progress, and sustained community-level COVID-19 outbreaks continue. |
| 2 | There is a possible new wave of the pandemic with COVID-19 activity rising again after a postpeak period. |
| 3 | The pandemic is in the postpeak period, and COVID-19 activity remains low. |
| 4A | The pandemic is considered over, but SARS-CoV-2 continues to circulate at low levels. There is evidence that the vaccine (or previous infection) provides long-term protection against COVID-19, but a routine vaccination program may be required for new cohorts that are immunologically naive. |
| 4B | The pandemic is considered over, but SARS-CoV-2 continues to circulate at low levels. There is evidence that the vaccine (or previous infection) does not provide long-term protection against COVID-19 and a routine vaccination program will be required for much of the population. |