Listen: A 90 Percent Effective Vaccine

Pfizer announced this week that early data show its vaccine to be “more than 90 percent effective.” But what does that actually mean? And does it change the timeline for a return to “normal life”?

Stephen Thomas, the chief of infectious disease at SUNY Upstate Medical University and the lead principal investigator of the Pfizer vaccine trial, answers questions on the podcast Social Distance from staff writer James Hamblin and producer Katherine Wells.

Listen to their conversation here:

Subscribe to Social Distance on Apple Podcasts, Spotify, or another podcast platform to receive new episodes as soon as they’re published.

What follows is a transcript of their conversation, edited and condensed for clarity:

James Hamblin: Your hospital is one of many sites for the clinical trial of the Pfizer COVID-19 vaccine. Could you lay out the basic facts here?

Stephen Thomas: Pfizer and BioNTech have partnered to develop a COVID-19 vaccine. There is a Phase III trial going on globally—about 140 sites around the globe. And SUNY Upstate in Syracuse, where I work, is one of those sites. We’ve been enrolling volunteers since July.

Hamblin: And now you are the lead principal investigator for this global trial.

Each of those 140 or so sites will have a principal investigator: the