Even though this was test-tube research and the new strain has not yet been shown to be infectious in animals, the scientists involved say it offers important clues as to how prion diseases cross between species.

BBC: NEWS | Health | How BSE may have infected humans

You are given the following information. (a) In random testing, you test positive for a disease. (b) In 5% of cases, this test shows positive even when the subject does not have the disease. (c) In the population at large, one person in 1, 000 has the disease.

ECONOMIST: Getting the goat

Even some experts who have helped test Fosamax say this broader group is being overtreated.

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