Scientists first discovered the fungus that is turning banana plants into this rotting, fibrous mass in Southeast Asia in the 1990s. Since then the pathogen, known as the Tropical Race 4 strain of Panama disease, has slowly but steadily ravaged export crops throughout Asia. The fact that this vicious soil-borne fungus has now made the leap to Mozambique and Jordan is frightening. One reason is that it’s getting closer to Latin America, where at least 70% of the world’s $8.9-billion-a-year worth of exported bananas is grown.

But the bigger difference now is that, compared its 20th-century cousin, Tropical Race 4 is a pure killing machine—and not just for Cavendishes. Scores of other species that are immune to Race 1 have no defenses against the new pathogen. In fact, Tropical Race 4 is capable of killing at least 80%—though possibly as much as 85%—of the 145 million tonnes (160 million tons) of bananas and plantains produced each year, says Ploetz.

And at $8.9 billion, bananas grown for export are only a fraction of the $44.1 billion in annual banana and plantain production—in fact, bananas are the fourth-most valuable global crop after rice, wheat, and milk. Where are the rest of those bananas sold? Nearly nine-tenths of the world’s bananas are eaten in poor countries, where at least 400 million people rely on them for 15-27% of their daily calories. And that’s the really scary part. Since the first Panama disease outbreak, bananas have evolved from snacks into vital sustenance. And this time there’s no back-up banana variety to feed the world with instead.