The U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) announced that it had identified the fourth case of Bovine Spongiform Encephalopathy (BSE) in an animal that was sampled for the disease in a facility in central California. APHIS has continued the investigation in collaboration with California public health professionals. The U.S. Food and Drug Administration (FDA) is working to investigate feed for the time period leading to the infection.

BSE, colloquially known as mad cow disease, is described by the U.S. Centers for Disease Control and Prevention (CDC) as a progressive neurological disorder of cattle that results from infection by an unusual transmissible agent called a prion. The nature of the transmissible agent is not well understood. Currently, the most accepted theory is that the agent is a modified form of a normal protein known as prion protein.

ABC WEAR News notes that there have been four human cases of mad cow in the U.S., with the most recent in Texas. Mad cow is a rare brain disorder that is believed to be caused by consumption of contaminated beef products. In each of the three prior cases, infection likely occurred outside the U.S.

The most recent patient is no exception. Extensive travel in Europe and the Middle East lead to the conclusion that an infection may have occurred outside the U.S. Unfortunately, there is no cure for mad cow and the disease is inevitably fatal.