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Topic: Mad cow disease

Mary Mallon(1870?-1938), known as "Typhoid Mary". She was the first person identified as a carrier of typhoid bacilli in the United States. Herself immune to the disease, she spread typhoid while working as a cook in the New York City area. She is pictured here after having been institutionalized on Brother Island where she stayed from 1914 until her death in 1938. (Getty Images/Bettmann)

Why finding patient zero matters

Mary Elizabeth Williams
In this photo taken on Tuesday, April 15, 2014, a Norwegian Red calf waits for food inside a farm in the village of Kozarac, near Bosnian town of Perijedor, 250 kms northwest of Sarajevo. Bosnian farmer Jusuf Arifagic invested eight million euro into the luxury farm that started four months ago with the import of 115 Norwegian Red Cows - a type of tough and hornless animal bred in Norway over the past 75 years to produce more and better milk than the usual cow known in the Balkans. He plans to expand into the biggest facility keeping this type of animal in Europe with 5,000 cows. In a country where half of the population is living in poverty, his animals sleep on mattresses in a barn with a computerized air condition and lighting system. They are bathed regularly, get a massage whenever they feel like it and receive the occasional pedicure.(AP Photo/Amel Emric) (AP Photo/Amel Emric)

Mad cow in the U.S.

Martha Rosenberg - Alternet
(Viktor1/Shutterstock)

Lindsay Abrams

Brad Jacobson