Mad Cow not so easy to spot

Health News Article | Reuters.com: WASHINGTON (Reuters) - The agent that transmits mad cow and related diseases may spread further in the body of an animal suffering from certain illnesses, scientists said on Thursday.

Their finding raises the question of whether measures aimed at curbing the spread of mad cow disease, or bovine spongiform encephalopathy, are adequate, the researchers said.
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Scientists have believed that BSE-causing prions are limited to the brain, spleen, spinal cord and lymph tissue, although some tests have suggested blood and muscle tissue may also harbor the prions.
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People who eat BSE-infected beef products can develop a related human brain disease called variant Creutzfeldt-Jakob disease or vCJD. There is no treatment or cure. It has killed 148 Britons, and five Britons are alive with the disease, according to the British Department of Health's monthly report on the disease.

The World Health Organization says it has reports of six cases in France, one in Ireland, one in Italy, one in Canada and one in the United States.
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The study suggests that even symptom-free animals may also have prions in their livers, kidneys and pancreases.