Another case of “mad cow” disease may have been found in the United States, the U.S. Agriculture Department announced Thursday, Nov. 18.

Previous cases of the disease had a significant impact on truckers who haul cattle.

The Ag Department is sending samples from the test to USDA’s National Veterinary Services Laboratories, the lab that handles confirmation of tests for bovine spongiform encephalopathy – the formal name of mad cow disease.

“Early this morning, we were notified that an inconclusive BSE test result was received on a rapid screening test used as part of our enhanced BSE surveillance program,” Andrea Morgan, associate deputy administrator of the Animal and Plant Health Inspection Service, said in a prepared statement. “The inconclusive result does not mean we have found another case of BSE in this country.”

Morgan said test results that would confirm whether or not the cow had the illness were expected in four to seven days.

In 2003, a cow in the province of Alberta that was slaughtered in January was diagnosed with the illness. It led the U.S. government to cut off beef shipments across the U.S.-Canadian border, severely impacting the beef industry – and the truckers who haul the beef.

The first U.S. case was detected in Washington state in December of 2003. In response to that announcement, eight nations in Asia banned American beef imports, and some – including Japan, the No. 1 importer of U.S. beef, South Korea, the No. 2 importer and No. 3 U.S. beef customer Mexico – recalled what was already on the shelves.

Bovine spongiform encephalopathy is a chronic, degenerative disease affecting the central nervous system of cattle, according to the USDA Web site. Worldwide, more than 180,000 cases have been reported since it was first diagnosed in 1986 in Great Britain. More than 95 percent of all mad cow cases have been in that country.

There is no treatment, the USDA said, and all affected cattle die.

The human form of the disease is called Creutzfeldt-Jakob Disease. That illness is thought to be caused by people eating specific parts of an affected cow such as brain and spinal cord.