I wonder how accurate those numbers are. If breakthrough cases are more likely to be asymptomatic among younger demographics, it's possible that those infections were never caught or recorded, skewing the data towards those who are more likely to see symptoms and get tested.
Yes, that's an important point, and they're aware of that. They do mention somewhere that they know that these numbers underestimate the true infection rate, and that may be why they stopped recording infections and concentrated on the more accurate measurements of hospitalizations and deaths. Many of these were not actually hospitalized FOR covid, but for something else, and they got tested in hospital, so this did catch some asymptomatic infections.
Here's their latest data
Hospitalized or fatal vaccine breakthrough cases reported to CDC as of July 6, 2021:
5186 cases, 75% are >65 years old.
988 deaths, though 255 were not considered deaths due to covid.
https://www.cdc.gov/vaccines/covid-19/health-departments/breakthrough-cases.htmlAll breakthrough infections reported Jan 1- April 30:
10,262 cases, median age was 58 years.
At that earlier time, 160 patients had died, and their median age was 82.
https://www.cdc.gov/mmwr/volumes/70/wr/mm7021e3.htmI had started recording the early breakthrough cases, but the CDC seemed to be doing a better job, so I stopped.
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