You know it's never good when a public health scientist starts off a tweet with "HOLY MOTHER OF GOD"

[mnhtnbb]

4. Definition of a pandemic

A pandemic is an epidemic of disease that has spread across a large region; for instance multiple continents, or even worldwide.

Apply thermonuclear to that...

A thermonuclear weapon, fusion weapon or hydrogen bomb, is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation atomic bombs, a more compact size, a lower mass or a combination of these benefits

So I would interpret the phrase to mean this virus is going to spread faster, farther, and with greater mortality and morbidity consequences than we have seen with normal virus activity.

In other words, I am happy I have no air travel planned for at least another 5 weeks and I won't be headed to Asia.