A California dairy cow has been found to be the host of “mad cow” disease–otherwise known as bovine spongiform encephalopathy–and has been destroyed. Officials say there is no need to panic as a single case does not necessarily spell out an outbreak, but they did say that the form of the disease found in this particular cow was “atypical”; the cow tested positive for a “very rare form of the disease not generally associated with an animal consuming infected feed,” according to the USDA.

No parts from the infected animal were distributed for human consumption, but that hasn’t stopped the U.S. cattle markets from plunging today as word got around, as people no doubt were reminded of the 1993 outbreak in the U.K. that claimed 150 human lives and more than 180,000 cows. And while the U.S.D.A. is still trying to trace the origin of this case, there will no doubt be many Americans who keep beef off the dinner table.