How many people need to be vaccinated for life to go back to normal?

In lieu of any other successful containment and mitigation strategies for the pandemic, Covid-19 vaccines have become the de-facto final hope for ending the pandemic. To return to pre-pandemic life, we first have to get to a point that researchers call “herd immunity,” explains Steven Singer, an immunologist at Georgetown University. Herd immunity occurs when enough people have gotten vaccinated against a disease to drastically reduce the spread of the virus to others—even to the point where it can’t happen at all.