The Centers for Disease Control and Prevention has identified approximately 5,800 people who have been fully vaccinated who have contracted COVID-19 so far, a fraction of the 66 million Americans who have been vaccinated.
Why it matters: The infections, called ‘breakthrough cases’, are rare. The findings are consistent with previous studies suggesting that positive coronavirus cases are extremely unlikely among vaccines, and that the vaccines prevent serious diseases.
- “As seen with other vaccines, we expect thousands of breakthrough cases through vaccines to occur, even if the vaccine works as expected,” the agency said in a statement Thursday.
By the numbers: About 40% of the infections were in people older than 60, but breakthrough cases occurred among all age groups.
- 65% were female and 29% of the breakthrough infections were reported asymptomatically.
- It is known that 7% of people with breakthrough infections were hospitalized, and 1%, or 74 people, died.
The state of affairs: Vaccine cases occur when the body does not have an adequate immune response, or if immunity fades over time, NIAID director Anthony Fauci said on Monday.
- “We see it with all vaccines in clinical trials,” Fauci said. “And in the real world, no vaccine is 100% effective or effective, which means you will always see breakthrough infections, regardless of the effectiveness of your vaccine.”
- Two studies published in the New England Journal of Medicine over the past month, percentages of breakthrough cases among fully vaccinated health workers have shown just as small.
What to look for: The CDC said it collects genomic sequences on respiratory samples from breakthrough patients to further understand whether any of the variants affect the effectiveness of a vaccine.
- To date, it has not identified any unexpected patterns in terms of demographics or vaccine characteristics.