The CDC stopped monitoring non-severe COVID-19 cases among vaccinated people in May.
It's hard to assess Delta's risk without knowing what mild breakthrough cases look like — or whether they're becoming more common.
COVID Vaccines still seem highly effective against the variant, though
The COVID vaccines reduce the severity of disease – at least for several months. The Definition of a vaccine is "a substance used to stimulate the production of antibodies and provide immunity against one or several diseases"
