USA: 20% vaccine breakthrough in Snohomish County, Washington State “In May 2021, fewer than 5% of cases were among vaccinated individuals. More... August 25, 2021 Coronaheadsup.com B.1.617.2, Coronavirus, Delta, Infection, Janssen, Moderna, Pfizer/Biontech, Testing, Transmission, USA, Vaccine, Vaccine Breakthrough, Vaccine Waning, Washington State