A virus never before seen in the U.S. has killed millions of baby pigs in less than a year, and with little known about how it spreads or how to stop it, it's threatening pork production and pushing up prices by 10 percent or more.
Scientists think porcine epidemic diarrhea, which does not infect humans or other animals, came from China, but they don't know how it got into the country or spread to 27 states since last May. The federal government is looking into how such viruses might spread, while the pork industry, wary of future outbreaks, has committed $1.7 million to research the disease.
The U.S. is both a top producer and exporter of pork, but production could decline about 7 percent this year compared to last—the biggest drop in more than 30 years, according to a recent report from Rabobank, which focuses on the food, beverage and agribusiness industries.
Already, prices have shot up: A pound of bacon averaged $5.46 in February, 13 percent more than a year ago, according to the U.S. Bureau of Labor Statistics. Ham and chops have gone up too, although not as much.
Farmer and longtime veterinarian Craig Rowles did all he could to prevent PED from spreading to his farm in Iowa, the nation's top pork producer and the state hardest hit by the disease. He trained workers to spot symptoms, had them shower and change clothing before entering barns and limited deliveries and visitors.
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Despite his best efforts, the deadly diarrhea attacked in November, killing 13,000 animals in a matter of weeks, most of them less than 2 weeks old. The farm produces about 150,000 pigs each year.