How Effective Is AstraZeneca’s COVID-19 Vaccine? Here’s What Experts Know So Far

Stories quote John A. Sellick Jr., DO, professor of medicine in the Division of Infectious Diseases, on the effectiveness of AstraZeneca’s COVID-19 vaccine. “Potentially, the first dose of the vaccine gives a lot of protection, but you’re going to need the second dose to get good, durable protection,” said Sellick.