In addition, eight more Canadian cows apparently came into the United States in 2001 with the 74 that contained the cow in Mabton, Wash., that tested positive for mad cow on Dec. 23, the U.S. Department of Agriculture said in a news briefing Monday.
"The additional eight (cows) came on a subsequent shipment," USDA's chief veterinary officer Ron DeHaven said.
"We don't know at this point where those animals are," DeHaven said. "It's our understanding all of them did come into the state of Washington," he said, adding that authorities are currently trying to locate their whereabouts.
The woman, who lives in Williams, Ore., told United Press International the meat was purchased and consumed before the mad cow case or the recall was announced.
She declined to give her name because her family has business contacts with many ranchers but said she purchased the meat from a small grocery store in Murphy, Ore., on Dec. 20 and she and her husband ate it the next day. The mad cow case was not announced until Dec. 23 and the recall was not initiated until Dec. 24.
The USDA recalled 10,000 pounds of beef that may have contained meat from the Holstein cow in Mabton. The agency said Sunday the meat went to Guam and eight states -- California, Nevada, Oregon, Washington, Alaska, Hawaii, Idaho and Montana.
Officials said Monday new information indicated the meat may have been distributed to 42 additional facilities.
The vast majority of the additional product -- at least 80 percent -- was distributed to the states of Oregon and Washington, said Kenneth Petersen of USDA's Food Safety and Inspection Service.
The mad cow pathogen, known as a prion, can infect humans and cause a fatal condition called variant Creutzfeldt-Jakob disease that deteriorates the brain and typically kills the person within a year of developing symptoms.
The Oregon woman said she was concerned about the possibility she or her husband had acquired vCJD from eating the beef. She still has some of it saved in her freezer and is trying to find out if it is possible to test it for the presence of mad cow prions.
USDA officials said the recall was initiated out of an abundance of caution and the meat probably did not pose a risk to consumers because the most infectious parts of the animal -- the brain, spinal cord and lower intestines -- had been removed.
The watchdog group Public Citizen, however, warns consumers to avoid certain cuts of meat because they can contain nervous tissue, such as the brain and spinal cord. These cuts of meat include beef cheeks, neck bones, T-bone steaks and any meat that comes from the head or spinal column.
Public Citizen also advises consumers to avoid ground beef, hog dogs, salami and bologna because they are sometimes made from meat processed by advanced meat recovery machines that can contaminate the meat with nervous tissue.
USDA's Petersen said AMR machines were not used to process any of the recalled beef.
Dalton Hobbs, spokesman for the Oregon Department of Agriculture, told UPI, "There's a good likelihood that people have consumed some of this recalled product" because much of the meat was turned into ground meat, which is typically consumed shortly after purchasing. The infected cow was slaughtered on Dec. 9 and distributed to commercial establishments a few days after that.
The Oregon Department of Agriculture has received calls from consumers worried about whether they consumed some of the recalled beef. But Hobbs said his department cannot confirm whether the consumed beef was subject to the recall because the USDA has not provided state officials with a list of retailers or products involved.
The recall came from the federal level and is being "managed and overseen by the USDA," Hobbs said. "We wouldn't really have any role in that unless asked by the USDA to assist and we have not been asked by them to assist," he said.
So far, the large supermarket chains of Albertson's, Safeway, WinCo and Fred Meyer are known to have received some of the recalled beef, Hobbs said. Some smaller stores, so-called "mom and pop shops," also may have received the beef, he said.
The Oregon woman said in light of the mad cow case she would only purchase beef from organic producers. "This is the end of the big cattle producers, at least in our family," she said.
The USDA investigation has also confirmed the age of the infected cow as 6.5 years old, DeHaven said. This is important, he said, because it means it was born before Canada imposed its ban on feeding cattle tissue back to cows and shows that ban is effective in preventing the spread of the disease.
Feeding infected cow tissue back to cattle is thought to amplify the disease and both the United States and Canada imposed a ban on the practice in August 1997. This indicates the animal was born approximately a few months before the ban.
However, Canadian officials told UPI in July after a case of mad cow was discovered in an Alberta cow that some feed manufacturing firms had violated the feed ban in recent years and some had probably violated the ban when it first went into effect.
Sergio Tolusso, feed program coordinator at the Canadian Food Inspection Agency, told UPI that about 3 percent of Canada's commercial feed manufacturers were in violation in 2001-2002.
Compliance rates were not available for 1997 to 1999, but he said the agency "didn't really get geared up to doing inspections" until 1998 and officials did not begin doing routine inspections until 1999.
In addition, Dr. Robert Hills with Health Canada, said some farmers in Canada probably feed tissues from cows to other cattle.
Steve Mitchell is UPI's medical correspondent. E-mail firstname.lastname@example.org
Notable deaths of 2014 [PHOTOS]