The Agriculture Department says there's "no cause for alarm" in connection with the case of mad cow disease that has surfaced in a dairy cow in California.

Officials say the cow was not headed for the nation's food supply, and posed no danger. The department's chief veterinary officer, John Clifford, says U.S. meat and dairy supplies are safe.

This is the fourth such cow discovered in the United States the government began inspecting for the disease to keep the food supply safe. The first was in 2003.

Mad cow disease can be fatal to humans who eat tainted beef. Eating contaminated meat is linked to a rare and deadly nerve disease.

The World Health Organization says humans can't be infected by drinking milk from infected animals.

The disease is always fatal in cattle. An outbreak in the United Kingdom that peaked in 1993 was blamed for the deaths of 180,000 cattle and more than 150 people.


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