The state of Washington has a separate section on their site where they report
Breakthrough Cases among the fully vaccinated and boosted.
On page 6 at the above link there's an interesting graph that shows Breakthrough Cases among the fully vaccinated and boosted as a percentage of new cases.
The data is presented by week dating back to the beginning of vaccine rollout.
There's also a line showing the 7 day avg of breakthrough cases among the fully vaccinated and boosted as a pct of new cases each week.
The breakthrough cases among the fully vaccinated and boosted are indicated with blue shading, and the cases among the unvaccinated are indicated with gray.
If you look at the graph across the arc of the Pandemic you'll notice:
There were almost no breakthrough cases at first.
The first breakthrough cases began showing up in February, 2021.
By the midsummer 2021 about 30% of all new cases were breakthrough cases.
Since January, 2022 more than 50% of all new cases were breakthrough cases.
And since late March, 2022 more than two thirds of all new cases have been breakthrough cases.
clickable thumbnail below
-jp
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