Inexplicably the CDC only counts breakthrough cases, in which a vaccinated person contracts Covid, when they result in hospitalization or death. If that standard had been in effect during the entire pandemic, case counts probably would have been cut at least 50 percent. From Megan Redshaw at childrenshealthdefense.org:
As the number of breakthrough COVID cases continues to climb, there is growing concern fully vaccinated people may be more vulnerable to serious illness than previously thought — and some fully vaccinated people now sick with the virus are speaking out.
According to the most recent data from the Centers for Disease Control and Prevention (CDC), there were 9,716 breakthrough cases resulting in hospitalization or death as of Aug. 16. However, the agency states those numbers are underreported. On May 1, the CDC made a decision to stop tracking all breakthrough cases and instead only track cases in the fully vaccinated that resulted in hospitalization or death.
In an interview with PBS News Hour, Jessica Malaty Rivera, an infectious disease epidemiologist and research fellow at Boston Children’s Hospital and former science communications lead at the COVID Tracking Project, said not tracking breakthrough data with as much granularity as we would hope is “basically creating blind spots in our understanding of the true impact of the virus, especially the variants that are circulating so widely in the United States.”
Rivera said she has yet to see an explicit explanation for why the CDC stopped tracking all breakthrough cases. “I’ve heard rumors of things like lack of resources, lack of funding, lack of staff. But to me, it seems pretty, from an epidemiology standpoint, not defensible,” she said.