A case of so-called “mad cow disease” was found in a California dairy cow last week. The disease, known to veterinary scientists as bovine spongiform encephalopathy (BSE), is fatal, and can be transmitted from cow-to-cow or cow-to-human through the ingestion of contaminated tissue. There is no evidence BSE spreads to humans — the human form of the disorder is called Creutzfeldt-Jakob disease — through drinking milk. As such, authorities claim that the infected animal (which is being held and will be destroyed) posed no risk to humans.