Talk of mad cow disease tends to make people nervous - with reason - even when the risk is low. Such concern has led to a recent recall of beef products.

Deaths tied to mad cow disease are incredibly rare, but they still can and do occur — a fact US health officials and the public are being reminded of this week.

A case of mad-cow disease has been located in a cow in California, but the USDA has announced that the discovery poses no risk to human health or the food supply.