An epidemic of African Swine Fever is sweeping through China's hog farms, and the effects are rippling across the globe, because China is a superpower of pork. Half of the world's pigs live in China — or at least they did before the epidemic began a year ago. "Every day, we hear of more outbreaks," says Christine McCracken, a senior analyst at RaboResearch, which is affiliated with the global financial firm Rabobank. McCracken and her colleagues now estimate that by the end of 2019, China's production of pork could be cut in half. "That's roughly 300 million to 350 million...