On Jul. 27, 2021, the National Institutes of Health announced that the COVID-19 vaccine AZD1222, when delivered into the nose of research hamsters and macaques infected with SARS-CoV-2, protected their lungs from disease andﾗmost importantlyﾗreduced virus shedding from the nose.

NIAID researchers and colleagues published the work in Science Translational Medicine. Various COVID-19 vaccines in use are delivered into the arm and may not reduce virus shedding, which is believed to be the primary route of person-to-person virus transmission.