Federal regulators have received reports of 25 people falling ill, most likely from raw almonds supplied by Paramount Farms in California. Paramount has voluntarily recalled 13 million pounds of raw almonds, and the size of the recall announced this week is likely to grow as federal investigators continue to identify distributors and repackagers of almonds that originated from Paramount.
The recall covers millions of packages sold under a variety of brand names across the country as well as almonds shipped to eight countries. The FDA has received reports of salmonella enteritidis, a type of food poisoning, in at least six states so far. No fatalities have been reported.
Salmonella in almonds is rare — this is only the second reported outbreak — and consumers have been stunned by the news.
"This is crazy. ... I'm shocked," said Mitra Muscarolas, a kindergarten teacher shopping Friday at a California Costco store. "I usually associate it with eggs and chicken. How do you get salmonella in almonds?"
So far, investigators have found no trace of salmonella in any of the recalled almonds or at Paramount. Experts say it is possible the outbreak may never be traced to its source.
"It wouldn't surprise me if they never find it," said Linda Harris, a food safety microbiologist and professor at the University of California, Davis. "It's likely even the product that had salmonella in it had it in very low levels. It may be that all the almonds that are positive have already been consumed. The chances of finding it under those circumstances are pretty slim."
An epidemiologist for the state of Oregon, Dr. William E. Keene, said the salmonella outbreak may have gone on for 18 months.
"This is an unusual outbreak ... because the cases were so few and far between," Keene said. "We are working with other states and countries now to establish just how far back this problem went."
Paramount Farms said all tests on its equipment and current crop have been negative for the presence of salmonella. The company said it also purchased some almonds from another source last year and is testing that as well.
"We're trying to trace this back to the source," Paramount spokesman Chris Tuffli said.
The first salmonella outbreak in almonds occurred in 2001. Traces of salmonella were found in almonds on store shelves and traced back to three farms, according to the Almond Board of California. Paramount was not involved.
"Prior to 2001, we had no knowledge of any salmonella or pathogen contamination," said Richard Waycott, president and chief executive of the Almond Board of California. "We've been trying to learn as much as we can on how this could happen and preventing it."
The industry has spent about $4 million to improve manufacturing and agricultural practices and has been examining technologies, including pasteurizing the almonds with low heat or gas, to prevent salmonella contamination, he said.
Heat, which can come from any kind of cooking, roasting or commercial processing of almonds, is usually sufficient to kill bacteria, experts said. Blue Diamond, a cooperative that represents about two-thirds of California's almond growers, began pasteurizing their almonds three years ago after the last outbreak.
Paramount Farms has not pasteurized raw almonds in the past, but two weeks ago began to use a gas method of pasteurization for all its raw almonds, the company said.
About 5 percent of all almonds consumed in the United States are consumed raw, according to the industry. The rest are processed and used in breakfast cereals, health bars, ice cream and other products.
California accounts for 100 percent of U.S. almond production and expects production to grow by at least 50 percent over the next five years. California also produces about 80 percent of the world's almonds. The next largest producer is Spain.
The industry does not expect the economic impact of the current recall to be overwhelming.
"We know the extent of this incident has a narrow scope to it," Waycott said. "We are doing all we can to ensure our consumers and customers they are perfectly safe to buy our product outside of the recall."
The almonds have been distributed in Mexico, Japan, Korea, Taiwan, Malaysia, France, England and Italy, the FDA said.
The initial recall covered 2.7 million packages of raw almonds sold under the brand names Kirkland Signature, Sunkist and Trader Joe's.
On Thursday, Kerry Inc. of Beloit, Wis., recalled almonds sold under its Pacific Seasonings' Gold Shield brand in Oregon, Washington, Idaho, Montana, Alaska, Northern California, Hawaii and Guam.
Seattle-based Metropolitan Market said it was recalling whole and diced raw almonds at its four stores in the Seattle area. The almonds were packed in 8-ounce and 16-ounce clear, square packages with the Metropolitan Market White Scale labels and sell-by dates of Feb. 1 to May 31.
Nationally, the FDA has ordered the recall of raw almonds with a best-before date of Aug. 21, 2004 or later.
Consumers who have the recalled almonds are asked to return them to the stores where they bought them. People with questions about the call can reach Paramount Farms at 800-496-5168.
The FDA has received reports of salmonella enteritidis, a type of food poisoning, in Alaska, Arizona, Oregon, Washington, Utah and Michigan. Symptoms of the illness include fever, diarrhea, nausea, vomiting and abdominal pain.
Scientifically, it is possible to treat the almonds, then return them to the marketplace. That was done after the 2001 outbreak, although in that case, most of the almonds had been shipped in bulk and had not yet made it to smaller packages.
It is not known yet if the recalled almonds will be treated and returned to store shelves.