CDC ReportsA new report from the Centers for Disease Control and Prevention (CDC) has important findings about COVID-19 breakthrough cases among fully vaccinated individuals:

  1. It’s extremely rare for a breakthrough case to lead to severe outcomes.
  2. When a severe outcome such as intensive care admission does occur from a breakthrough case, the individual is almost certain to have at least one risk factor such as advanced age, suppressed immune system, or chronic disease. 
  3. In the extraordinarily rare instance of a breakthrough case resulting in death, several risk factors usually are involved. 

It certainly isn’t pleasant to discuss breakthrough cases that result in severe outcomes. But this study, which involves patients seen at 465 U.S. healthcare facilities from December 2020 to October 2021, is yet another example of the protection offered by COVID-19 vaccines. 

Among more than 1.2 million fully vaccinated adults in the study, just 327 of them were hospitalized due to COVID-19. Of those hospitalized, 189 of those (1.5 per 10,000) had severe outcomes that included acute respiratory failure, the need for noninvasive ventilation, or intensive care unit admission. The case data showed that all of those who experienced severe COVID-19 outcomes had at least one of these risk factors:

  • age 65 and older
  • suppressed immune system
  • pulmonary disease
  • chronic kidney disease
  • neurologic disease
  • cardiac disease

Of the 36 fully vaccinated individuals in this group who died (0.3 per 10,000), about three-quarters of them had at least four of these risk factors.

If you have one or more of these risk factors, this research offers another reason to get your COVID-19 booster dose if you haven’t already done so. A booster dose, which helps make sure your vaccine protection is up to date, is important for everyone but is especially so for people who have weakened immune systems and other risk factors. The findings also speak to the need for at-risk individuals to reduce exposure (and for others to reduce the chances of exposing them to COVID-19), manage chronic diseases, and receive pharmaceutical therapies like monoclonal antibodies or antivirals to protect against severe outcomes.

COVID-19 vaccines and boosters continue to prove their value at preventing severe disease and reducing the risks when there is a breakthrough case. Our most recent analysis of outcomes by vaccination status found that those who weren’t vaccinated were 31.1 times more likely to die from COVID-19 and 4.9 times more likely to test positive.

If you aren’t already vaccinated or have yet to receive your booster dose, I encourage you to find a provider at and roll up your sleeve as soon as possible.