“I am worried we’re not going to be able to just press a button and go from pandemic to no pandemic. It will take a lot of time, and it may not happen to quite the extent that we might imagine.”

Yonatan Grad, a professor of immunology and infectious diseases, is trying to temper expectations of how quickly normalcy may return after the approval of a COVID-19 vaccine.

According to Dr. Anthony Fauci, the director of the National Institute for Allergy and Infectious Diseases, “herd immunity” will only be achieved after at least 70 percent of the population has been exposed to the virus through a vaccine or prior infection.

CQ Roll Call health care reporter Emily Kopp breaks down why it may take longer than expected to return to normal once a vaccine is approved.

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