The CDC says a total of 10,262 SARS-CoV-2 vaccine breakthrough infections have been reported from 46 states and territories as of April 30, 2021. A vaccine “breakthrough” infection is a confirmed COVID-19 diagnosis in a fully-vaccinated patient. As of April 30th, approximately 101 million Americans have been fully vaccinated against SARS-CoV-2, the CDC reported.

According to the CDC’s Morbidity & Mortality Weekly Report, 64% of the breakthrough infections (in which lineage was available) were identified as SARS-CoV-2 variants of concern,” including the UK variant B.1.1.7 (56%), two California variants B.1.429 (25%) and B.1.427 (8%), a Brazilian variant P.1 (8%), and the South Africa variant B.1.351 (4%).

Additional observations include:

  • Among these 10,262 cases, 6,446 (63%) occurred in females, and the median patient age was 58 years (interquartile range = 40–74 years).
  • Based on preliminary data, 2,725 (27%) vaccine breakthrough infections were asymptomatic, 995 (10%) patients were known to be hospitalized, and 160 (2%) patients died.
  • Among the 995 hospitalized patients, 289 (29%) were asymptomatic or hospitalized for a reason unrelated to COVID-19. The median age of patients who died was 82 years (interquartile range = 71–89 years); 28 (18%) decedents were asymptomatic or died from a cause unrelated to COVID-19.

Read the full MMWR report here.