Paul Sakuma / AP file
Members line up for registers at a Costco warehouse store in Mountain View, Calif. Purchase records are being used more frequently by public health officials investigating outbreaks of foodborne illness.
If you have a warehouse membership card in your wallet or a supermarket shopper tag on your key chain, you might regard it as a good way to save money. But public health officials say it may be an even better way to save lives.
More local health departments -- along with state and federal investigators -- are relying on the detailed information about what went in consumers’ shopping carts to track down outbreaks of foodborne illness, experts say.
Take the outbreak of E. coli O157:H7 bacteria in organic spinach and spring mix salad greens that sickened 33 people in five states last fall, including new mother Erica Duerr, 32, of North Tonawanda, N.Y., and her mother-in-law, Beth Duerr, 60.
Erica Duerr already had been sick for nine days when Beth Duerr was struck with gastrointestinal symptoms so severe she had to be rushed to a local emergency room. That’s when local health department officials called, seeking her shopper card numbers.
“They went to the hospital and they got her info,” says Erica Duerr, a nurse who had just given birth to her second child. “They were actually able to track down where it came from.”
Data from Beth Duerr and others pointed to contaminated greens sold by Wegmans, a small Northeast grocery chain, but produced by State Garden of Chelsea, Mass. Seattle food safety lawyer Bill Marler sued the firm on the Duerr families' behalf.
Identifying exactly which products were purchased by victims of food poisoning has become a standard tool for public health investigators, said officials with the Centers for Disease Control and Prevention.
“We are definitely supportive of the use of shopper cards during these outbreak investigations,” said Casey Barton Behravesh, deputy chief of the CDC’s outbreak and prevention branch of the division of foodborne, waterborne and environmental diseases. “The product, the flavor, the lot code, the best by date: That is all tracked with these purchases.”
The CDC estimates that 48 million Americans get foodborne illnesses every year, 128,000 of them are hospitalized and 3,000 die.
Store cards are a rich trove for epidemiologists, who often are trying to track down suspect food a month or so after it was consumed because of the lag between when an illness strikes and when it gets reported, said Bill Keene, a senior epidemiologist with the Oregon Public Health Division. His state has been a leader in using shopper card data, along with Minnesota, but others are joining in, Keene said.
“We rely on people’s memories, which are quite fallible, and on our interviews, which are quite fallible,” Keene told NBC News. “Shopper club cards are a good source of finding out what people ate.”
Identifying the source of an outbreak early and accurately can get product off the shelves faster and point doctors toward the best treatment for victims, experts said.
The push appears to have begun back in 2009, when investigators were stumped after an outbreak of salmonella linked to salami and other deli meats sickened 272 people in 44 states. It was only when officials with Costco warehouse stores cooperated with health officials to review membership data that the source was pinpointed: pepper-crusted Italian-style meats made by Daniele International Inc.
Costco has been notifying consumers about food and other products recalls for safety reasons since the late 1990s, said Craig Wilson, the company’s vice president for food safety and quality assurance. But now, they’re being called on by public health officials at every level.
“It happens a couple times a week,” said Wilson. “It’s getting to be more of a norm.”
Most recently, CDC officials say they have been using shopper cards to investigate an outbreak of salmonella Heidelberg that has sickened at least 128 people in 13 states since June. The illnesses appear to be tied to poultry products from Foster Farms, a West Coast poultry producer.
The reasons may be obvious. About 80 percent of U.S. consumers belong to a shopper loyalty card program, and the average household now participates in more than six shopper programs, according to a report by the Food Marketing Institute.
Nearly 60 percent of retail grocery stores now offer shoppers cards, said Hilary Thesmar, vice president for food safety programs at FMI. The group's members go out of their way to cooperate with public health officials.
“The hardest ones are when they are looking for that food and they have the illnesses and they’re finding it’s hard to detect the source of the illnesses,” Thesmar said. “I know our members receive a lot of requests and they frequently comply with those requests.”
But it’s not always easy, Keene says. Stores provide data only with the permission -- usually written consent -- of the consumer and a verified shopper card or membership number. And disclosure rules vary from state to state, making some information more difficult to obtain.
“We won’t just release data,” said Wilson.
Those concerned about the potential for privacy violations say it’s not nearly tough enough, however. Shopper cards and membership stores that track your groceries are essentially creating a “food registry” of every meal you eat, said Katherine Albrecht, founder and director of CASPIAN, Consumers Against Supermarket Privacy Invasion and Numbering.
She worries that the information one day could be used to control consumers’ health decisions, particularly once federal health care reforms take full effect.
“Once the federal government is paying for your health, it becomes a public health issue what you put in your mouth,” she said, adding later:
“Public health officials want to know exactly what’s on your shelf. Today it’s salmonella, but tomorrow it might be cholesterol, or ice cream.”
In the meantime, though, health officials like Keene say they safeguard the data carefully and use it only as a tool to keep more people from getting sick.
“We are the government, but we aren’t that part of the government,” he said. “We’re the good guys.”
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