This weekend we are marking one of the most significant anniversaries in recent history.

Three years ago, March 11, 2020, the World Health Organization made this chilling announcement.

WTO has been assessing this outbreak around the clock and we're deeply concerned

both by the alarming levels of spread and severity

and by the alarming levels of inaction. We have therefore met the assessment

that COVID-19 can be characterized as a pandemic.

That was the Director General of the WHO, Tedros Audenham Gibriasis.

You were on to say that this pandemic was the first ever sparked by a coronavirus.

Now, there are many different kinds of viruses, right? But coronaviruses belong to a small

but important club, one for viruses with, quote, pandemic potential. Meaning they've got certain

characteristics that a pathogen needs in order to go global. I'm Rachel Martin, this is up for Sunday.

My colleagues on our global health and development team here at MPR are just wrapping up a series

called Hidden Viruses, how pandemics really begin. Their stories look at efforts to track these viruses

with pandemic potential, study them and hopefully stop them. Joining me now to talk about their work

is science reporter Ari Daniel. Hey, Ari. Hi, Rachel. It's great to be here.

I'm so glad that you're here. I have so many questions. I want to hear about this series,

but we're just going to put a spoiler alert at the top because I think this is the question

on everyone's minds. Are we any closer to being able to predict and possibly stop a future pandemic?

Well, Rachel, you know, if you ask a simple question, you're going to get a complicated answer.

I mean, I guess I could say that in some ways, yes, but in many ways, no, is that at all helpful?

No, it's not. Flush that out for me. Okay, so let me put it like this. We are getting better

at understanding what sets some of these viruses up to become pandemic level viruses.

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