The first doses of the COVID-19 vaccine have been given out across the United States. A common question is: If you’ve already had the novel coronavirus, do you still need to get vaccinated? Scientists believe people previously infected do have some level of protection, likely a couple of months, but they’re still in the process of understanding it all, says
Thomas A. Russo, MD, professor of
medicine and chief of the
Division of Infectious Diseases. “We don’t really have a great test to sift out of all the people infected, who may be a greater or lesser risk for subsequent reinfection,” he says. “So, for those that we’ve known have been infected, it’s just easier to go ahead and vaccinate them.” He notes: “As a community, we want a critical number of individuals to get vaccinated so we can achieve what we call herd immunity, where if you get a critical mass that is not susceptible to infection, the virus has nowhere to go, and then subsequent incidence of disease is very, very low or zero.”