6 sickened; Salmonella-contaminated blueberries from Georgia in 2010 tracked down by Minn. health types using GTINs and shopper cards


In August 2010, the Minnesota Department of Agriculture and Minnesota Department of Health investigated an outbreak of six cases of Salmonella Newport infection occurring in northwestern Minnesota, which identified fresh blueberries as the cause. Initially, traditional traceback methods involving the blueberryreview of invoices and bills of lading were used to attempt to identify the source of the outbreak. When these methods failed, novel traceback methods were used. Specifically, supplier-specific 12-digit Global Trade Item Numbers (GTINs) and shopper-card information were used to identify a single blueberry grower linked to cases, corroborating the results of a case-control study in which consuming fresh blueberries was statistically associated with illness (5 of 5 cases versus 8 of 19 controls, matched odds ratio [MOR] undefined, P = 0.02). Consuming fresh blueberries from retailer A was also statistically associated with illness (3 of 3 cases versus 3 of 18 controls, MOR undefined, P = 0.03). Based on initially incomplete evidence in this investigation, the invoices pointed to wholesaler A and grower A, based on first-in-first-out product rotation. However, when point-of-sale data were analyzed and linked to shopper-card information, a common GTIN was identified. This information led to an on-site record evaluation at retailer A, and the discovery of additional records at this location documented the supply chain from grower B to wholesaler C to retailer A, shifting the focus of the investigation from grower A to grower B. This investigation demonstrates the emerging concepts of Critical Tracking Events (CTEs) and Key Data Elements (KDE) related to food product tracing. The use of these shopper-cased data and the event data that were queried by investigators demonstrates the potential utility of consciously designed CTEs and KDEs at critical points in the supply chain to better facilitate product tracing.

Use of Global Trade Item Numbers in the investigation of a Salmonella newport outbreak associated with blueberries in Minnesota, 2010

Journal of Food Protection®, Number 5, May 2013, pp. 744-918 , pp. 762-769(8)

Miller, Benjamin D.; Rigdon, Carrie E.; Robinson, Trisha J.; Hedberg, Craig; Smith, Kirk E.


Fail: Hi, I’m from government, here to help; but shopper cards may actually help food safety efforts

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.

JoNel Aleccia of NBC News reports that more local health departments — along with state and federal investigators — are relying on the detailed 20100610_124707_bz10shopcard_200information about what went in consumers’ shopping carts to track down outbreaks of foodborne illness, experts say.

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.”

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.”

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.”

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.

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.”