The first new case of mad cow disease in the U.S. since 2006 has been discovered in a dairy cow in California, but health authorities said Tuesday the animal never was a threat to the nation’s food supply.
Agriculture Secretary Tom Vilsack said the finding posed “no risk to the food supply or to human health”, and swiftly assured consumers and global importers that there was no danger of meat from the California dairy cow entering the food chain.
There is no evidence that humans can catch mad cow disease — Bovine Spongiform Encephalopathy (BSE)– from drinking milk from an infected cow. The risk of transmission generally comes when the brain or spinal tissue is consumed by humans or another animal, which did not occur in this case.
The cow is not believed to have contracted the disease by eating animal feed, which is a scarier scenario because of the greater chance of spread of the disease to other cows.
The carcass of the cow is under examination and quarantine, and will be destroyed following an investigation, which includes tracing the history of the animal.
BSE is a fatal neurodegenerative disease in cattle that causes a spongy degeneration in the brain and spinal cord. BSE has a long incubation period, about 30 months to 8 years, usually affecting adult cattle at a peak age onset of four to five years, all breeds being equally susceptible.
BSE is transmitted to human beings by eating food contaminated with the brain, spinal cord or digestive tract from infected carcasses.
The human form of the disease is known as Creuzfeldt-Jakob disease or CJD, which is incurable and fatal. BSE in cows is believed to be the cause of CJD in humans.