'Mad cow' case confirmed by USDA

A South Korean employee displays local beef at a Lotte Mart as the store suspended sales of all US beef in Seoul on April 25, 2012. Two major South Korean retailers suspended sales of US beef after a new case of mad cow disease in California, and the government said it would tighten inspection of imports. AFP PHOTO / JUNG YEON-JE (Photo credit should read JUNG YEON-JE/AFP/Getty Images)
A South Korean employee displays local beef at a Lotte Mart as the store suspended sales of all US beef in Seoul on April 25, 2012. Two major South Korean retailers suspended sales of US beef after a new case of mad cow disease in California, and the government said it would tighten inspection of imports. AFP PHOTO / JUNG YEON-JE (Photo credit should read JUNG YEON-JE/AFP/Getty Images)

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    'Mad cow' case confirmed by USDA

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Elizabeth Cohen reports on the confirmed case of "mad cow" disease in California.