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A Break in the Case

Some critics of loyalty cards have decried them as an intrusion into consumer privacy or an unfair separation of shoppers into card holders and non-card holders. But recent applications of shopper cards have elevated them into a new realm that may prove more persuasive to critics: food safety. For example, a number of retailers now use card purchase data to contact shoppers who have bought products

Some critics of loyalty cards have decried them as an intrusion into consumer privacy or an unfair separation of shoppers into card holders and non-card holders. But recent applications of shopper cards have elevated them into a new realm that may prove more persuasive to critics: food safety.

For example, a number of retailers now use card purchase data to contact shoppers who have bought products subject to a recall. And more recently, shopper data has proved increasingly helpful to health officials trying to figure out the source of a foodborne illness.

The ability of shopper data to assist health investigators became dramatically clear in January when it enabled the Centers for Disease Control and Prevention (CDC), Atlanta, working with the Washington State Department of Health, to trace the source of a salmonella outbreak that infected 252 people in 44 states and the District of Columbia. The data was supplied by Costco, Issaquah, Wash.

As a club retailer, Costco requires consumers to sign up for a membership card, which allows the chain to collect data on all purchases. Costco has been sharing this data with state health departments for several years, said Craig Wilson, the company's assistant vice president of food safety and quality assurance. But the salmonella case was the first time Costco worked with both the CDC and state officials and the first time the CDC has used the data, he noted.

Conventional retailers also participated in the recent salmonella case and chains such as Wegmans Food Markets and ShopRite have made loyalty card data available to health authorities in other foodborne illness cases.

Last November, Washington was one of several states that began investigating a cluster of salmonella cases that first surfaced in July. As a result of this CDC-led investigation, in which ill people were extensively interviewed about foods they had consumed, salami was suspected to be a common source of the illness.

But that wasn't confirmed until, with the stricken individuals' permission, data was obtained from Costco that revealed that the majority had purchased packaged salami meats made by Daniele, a producer of Italian-style specialty foods, in Pascoag, R.I.

“Learning the specific brand and manufacturer provided a valuable break in the investigation,” said Kathryn MacDonald, an epidemiologist for the Washington State Health Department who was involved in the salmonella inquiry. “It's questionable whether the source would have been found without this assistance, as the investigation had gone on for some time, and the case interviews had not resulted in naming a particular product.”

Costco also provided information on when it received the Daniele products and when they went out on sale so that government officials “could do a reasonable traceback,” said Wilson.

Subsequent testing by the Rhode Island Department of Public Health found the Salmonella montevideo strain in samples of black and red pepper used in the production of Italian-style meats at Daniele. The company initiated a recall of its pepper-coated salame products, which encompassed 18 SKUs. It also acknowledged in a statement that “preliminary results” indicated 11 ill individuals had consumed salame products from its Daniele Italian Brand Gourmet pack.

The peppers used by Daniele were, in turn, traced to Wholesome Spice, Brooklyn, N.Y., and Mincing Overseas Spice Co., Dayton, N.J., both of which issued recalls. Two other companies supplied by Mincing — Dutch Valley Food Distributors and Frontier Natural Products Co-op — also announced recalls.

After these recalls were announced in January, Costco further leveraged its data to call all members nationally who purchased the recalled products, using an automated phone system. The same day a letter was mailed to the same members with more details on the recalls. Costco considers contacting members who purchased recalled products “a benefit of membership,” said Wilson.

Last month, the Washington, D.C.-based Center for Science in the Public Interest repeated its call for retailers to emulate Costco, Wegmans, Price Chopper Supermarkets, Kroger Co. and others that use card data to alert shoppers who bought recalled products. “If a retailer knows the address, phone number or email address of someone who has purchased contaminated peanut butter, spinach or salami, the company should take advantage of that opportunity to prevent future illnesses from recalled products,” said Sarah Klein, the CSPI's food safety attorney, in a statement on its website.


The value of shopper data in the salmonella case was that it filled in the gaps in information previously obtained by health officials during interviews with sickened individuals. “We found the majority of the ill people ate Italian-style deli meats like salami, but they had a hard time remembering brands or exact product details,” said Laura Bettencourt, epidemic intelligence service officer, CDC.

“It is very difficult to get complete and accurate food histories based on memory alone,” said MacDonald. “Often some time has passed between the illness and the outbreak investigation interview. Store receipts can be very helpful but are often not retained by the consumer.”

In some investigations, health officials have no idea what type of food may be involved. In those cases, comparing purchase records of affected individuals, if they shop at the same retailer, can be “a big clue,” said Kirk Smith, supervisor of the foodborne diseases unit for the Minnesota Department of Health. “You look at everything they bought over the previous two weeks and look for common items.”

In the salmonella case, Costco was contacted after the Washington State Health Department noticed that the majority of the sick people had shopped there. Local public health agencies received permission from “fewer than 10 ill shoppers” to ask Costco for their purchase data, said MacDonald. Bettencourt noted that in seeking the data, investigators only focused on “purchases of certain food items.” The department discovered that the majority of the ill people purchased the same product — the Daniele Italian-style deli meats — shortly before becoming sick, Bettencourt said.

Washington officials shared their results with the CDC, and in subsequent investigations of the salmonella outbreak in other states, more sick individuals were asked for permission to see their shopping data. Costco was again contacted and “gave everybody the same information” that was provided to Washington officials, said Costco's Wilson.

Meanwhile, the Food and Drug Administration, as well as the U.S. Department of Agriculture, “worked with other grocery stores on this case,” and their shopper data reflected what was determined at Costco, said Bettencourt, who could not name the stores.

CDC has attempted to use card data in the past in outbreak investigations, but this was the first time the agency was successful in “getting the exact product” that caused the illness from the card information, Bettencourt said. “It sped up the investigation.” She praised Costco for its cooperation and the prowess of its technology. “They have a very sophisticated system that allows them to pull specific product information very quickly.”

Bettencourt emphasized that the shopper data is treated with “the same confidentiality as medical records.” MacDonald added that public health agencies are required to keep all personally identified records collected in the course of a public health investigation confidential. “Confidentiality is a strict requirement for our employment, and we take that responsibility very seriously,” MacDonald said.

One of the lessons the CDC learned in the salmonella investigation is the need, in the case of club stores that issue different card numbers to individuals in the same family, to look at the shopper records of all family members, since any of them could have purchased the suspected product, not just the ill individual. “Once we realized that, we collected data on everyone who had a card number in a household with an ill person,” Bettencourt said.

Before the salmonella case, the Washington Health Department had sought shopper data from “a few retailers with varied responses,” said MacDonald. When shoppers have been asked for permission to see their data, most complied, but not all, she said. People who came down with a foodborne illness are usually “eager to assist efforts to determine the source of their illness and to prevent others from becoming ill.”

A few years ago, Costco provided shopper data that helped state authorities determine that almonds were the source of a large illness outbreak, said Wilson. “We get asked all the time.”


Minnesota only had a few cases of salmonella in the recent outbreak, said Smith of the Minnesota Department of Health. But his department, working through the state Department of Agriculture, also contacted Costco to obtain shopper records for one ill individual.

In this case, the individual was sickened by a different type of salmonella — Salmonella senftenberg, which was discovered with Salmonella montevideo in a four-pack deli tray made by Daniele after the initial link to Daniele was determined, Smith said. Costco's data confirmed that the sick person had purchased the same four-pack deli tray, he said, adding that the Salmonella senftenberg was “tangential to the main outbreak.”

Over the past few years, Minnesota, which is regarded as having one of the nation's best foodborne surveillance records, has leveraged shopper data in a few other outbreak investigations. Using shopper data is “such a great opportunity,” said Smith, “since we're interviewing people at least two to three weeks after they ate what made them sick.”

In one investigation involving two cases of an E. coli-induced illness, the sickened people lived in the same area and mentioned eating different kinds of steak. After getting permission to look at purchase data at a local Sam's Club, “we found they bought exactly the same kind of steak at the same store about three hours apart,” said Smith. The information was turned over to the USDA, which traced the steaks to their processing plant.

Wegmans, Rochester, N.Y., is another retailer that has shared shopper data with health departments, albeit on a small scale. In two separate cases, a single customer gave the chain permission to provide data on specific products consumed and the dates the products were purchased, in one case to a local health department, the other to the state, said Wegmans spokeswoman Jeanne Colleluori. “They were looking for verification of what they already had,” she said. “But it helped speed efforts to correct the situation.”

Wegmans is also one of the more proactive food retailers that alert loyalty card shoppers about recalled products. While most of these retailers do so for Class 1 recalls, Wegmans calls shoppers for both Class 1 and Class 2 recalls of its private-label products, said Colleluori. For national brands, it contacts shoppers for Class 1 recalls and Class 2 recalls involving gluten sensitivity. “Wegmans has a strong commitment to helping people with celiac disease,” she said.

Late last month, Wegmans issued a statement on its website describing its recall policies. To ensure that its Shoppers Club loyalty card database has current contact information in the event of a recall, “we encourage everyone to keep their contact information up to date, either on by clicking on Shoppers Club contact information, or by stopping at the service desk in our stores,” said Sherrie Diamond, the chain's recall coordinator, in the statement.

For more general outreach to consumers, Wegmans posts recall notices on its home page and even tweets about the recalls on Twitter. Its recall team briefs service desk employees and call center specialists so they can answer recall questions from customers.