An anonymous reader quotes a report from Ars Technica: Cases of COVID-19 are extremely rare among people who are fully vaccinated, according to a new data analysis by the Centers for Disease Control and Prevention. Among more than 75 million fully vaccinated people in the US, just around 5,800 people reported a "breakthrough" infection, in which they became infected with the pandemic coronavirus despite being fully vaccinated. The numbers suggest that breakthroughs occur at the teeny rate of less than 0.008 percent of fully vaccinated people -- and that over 99.992 percent of those vaccinated have not contracted a SARS-CoV-2 infection.
The figures come from a nationwide database that the CDC set up to keep track of breakthrough infections and monitor for any concerning signs that the breakthroughs may be clustering by patient demographics, geographic location, time since vaccination, vaccine type, or vaccine lot number. The agency will also be keeping a close eye on any breakthrough infections that are caused by SARS-CoV-2 variants, some of which have been shown to knock back vaccine efficacy. [...] The extraordinary calculation that 99.992 percent of vaccinated people have not contracted the virus may reflect that they all simply have not been exposed to the virus since being vaccinated. Also, there are likely cases missed in reporting. Still, the data is a heartening sign. As for the "breakthroughs," the agency says many of them occurred in older people, who are more vulnerable to COVID-19. There are some scattered through every age group, but more than 40 percent were in people ages 60 and above.
"We see [breakthroughs] with all vaccines," top infectious disease expert Anthony Fauci said in a press briefing earlier this week. "No vaccine is 100 percent efficacious or effective, which means that you will always see breakthrough infections regardless of the efficacy of your vaccine."
Read more of this story at Slashdot.