I'm Steve Strogatz, and this is The Joy of Why, a podcast from Quantum Magazine that takes you into some of the biggest unanswered questions in math and science today.

In this episode, we're going to talk about the science behind vaccines, specifically those developed to work against COVID-19, and what we can learn from this experience

of going through the pandemic. In the face of shutdowns and social isolation, researchers around

the globe went into overdrive to make a vaccine to battle SARS-CoV-2, the virus that causes COVID-19.

The accelerated efforts involved two new ways to make vaccines, one of them being the

mRNA vaccine that you probably heard of.

As with flu shots, developing vaccines for the coronavirus is tricky because it's a moving

target.

It's always evolving.

We make vaccines based on the versions of viruses that we see now, not on the versions that we think might evolve in the future.

My guest today, Dr. Anna Durbin, is a professor of International Health in the Bloomberg School of Public Health and the School of Medicine at Johns Hopkins. She also directs

their Center for Immunization Research. Dr. Durbin studies experimental vaccines for SARS-CoV-2,

but also for dengue, Zika virus, malaria, and more. She's also involved with vaccine safety

efforts through the CDC.

Dr. Durbin joins me now to share her insights into the science behind vaccines,

including some areas where we might consider focusing our efforts, both today and for future outbreaks.

Welcome, Dr. Anna Durbin.

Thank you so much. It's my pleasure to be here today.

Could we begin with kind of looking back first?

You know, we've been making and testing and approving and distributing vaccines for decades.

Tell us a little about that old system of vaccine making.

Let's begin with the strengths.

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