Last May, scientists met in Geneva, Switzerland, to update the World Health Organization’s plans for pandemic preparedness. It looks like a crisis could arrive sooner rather than later. Thanks to climate change and drug resistance, a handful of deadly organisms are spreading across the globe; some are poised to make a comeback in the U.S. after decades of absence.

Growth in international travel and increasing urbanization around the world are sure to make this century’s inevitable pandemic much worse, and experts at the Centers for Disease Control and Prevention (CDC) say we’re not at all prepared for what’s to come. But although bird flu has gotten most of the press (it’s still a threat to those in North America, as birds regularly migrate here from areas in Asia where the virus is firmly entrenched), here are five other diseases that deserve your attention.

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