So what do we know about breakthrough infections —  cases where fully vaccinated people test positive for COVID-19? Well, the Centers for Disease Control and Prevention is reporting that the cases are more common than they initially reported — but still make up a small fraction of total cases, and even fewer illnesses and deaths.

So should the vaccinated be worried? What precautions are necessary? And do the breakthroughs represent a vaccine failure or evidence of the shots’ success?

Here & Now‘s Peter O’Dowd talks to virologist Angela Rasmussen from the Vaccine and Infectious Disease Organization at the University of Saskatchewan.

This article was originally published on WBUR.org.

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