Sleuthing, and a Little Help from Consumers, Helps FDA Track Down Bacteria in Flour

Posted on June 28, 2016 by FDA Voice

By: Stephen Ostroff, M.D., and Kathleen Gensheimer, M.D., M.P.H.

When many people buy flour, they empty it into a canister and throw out the bag. But three people at the center of a recent outbreak of foodborne illness didn’t do that. They kept their flour in the original packaging, and in so doing enabled the FDA to track down what was making people sick.

Stephen Ostroff, M.D., FDA’s Deputy Commissioner for Foods and Veterinary Medicine

The story of the recent recall of 10 million pounds of baking and cooking flour is one in which federal agencies, consumers and the food company – in this case, General Mills – all had a role in doggedly tracking down the source of an outbreak that has made dozens of people across the country sick and getting the suspect product off the market.

It all began with a signal, or more accurately, with multiple signals that were monitored byFDA’s Coordinated Outbreak Response and Evaluation (CORE) network. This team looks for “signals” that may point to a pending outbreak, including reports of human illness from the Centers for Disease Control and Prevention (CDC), FDA-collected data on food samples and inspections, and related information on illnesses and inspections from state and local public health and regulatory agencies.

The signals this time came from CDC, which in February identified a string of illnesses that began in December as an outbreak of infections caused by Shiga toxin-producing E. coli O121. This pathogen is a much less common cause of foodborne illness than its better-known cousin E. coli O157. Investigators began to interview patients about the foods they had eaten in the week before they became ill. But identifying flour as the source of the outbreak was not easy. Initially, it seemed that produce or other foods might be the culprit.

Kathleen Gensheimer, M.D., M.P.H., director of FDA’s Coordinated Outbreak Response and Evaluation (CORE) network

Then there was a break. By April, investigators had found that all of the people interviewed in depth had been baking at home, and many of them said they used Gold Medal flour. Multiple interviewees also mentioned eating raw cookie dough that had been made at home with the flour.

CORE was now faced with the daunting task of proving that specific batches of flour caused the majority of the illnesses. The reports from some patients could not initially be confirmed because key information about the brand and lot numbers was not available – it had gone out in the garbage with the flour bags.

But in the weeks that followed, investigators made two important discoveries:

Three people who had become ill still had the original flour package. Two of the labels showed that the Gold Medal Brand flour had been packaged at a General Mills facility in Kansas City, Missouri, and that they were packaged on consecutive days. The third was made at that plant within a week of the other two.

And the FDA team became aware of illnesses linked to restaurants that would supply balls of raw dough for children to play with. These illnesses were among children who had eaten different meals at restaurants in separate states. The CORE team learned that the flour used by the restaurants during the estimated time of the children’s exposure was supplied by the same General Mills production facility.

The FDA decided not to wait for laboratory confirmation that there was E. coli in the flour before contacting the company. On May 27, FDA and CDC investigators briefed General Mills leadership about the information they had received from patients and on May 31 the firm voluntarily recalled a massive amount of flour — 10 million pounds produced in the Kansas City plant over a three-week period in November and December of 2015.

The FDA continued its analysis of a sample of flour collected from the home of a patient who had provided one of the labels. Laboratory microbiologists at the agency confirmed the presence of E. coli O121 in that flour sample. On June 10, FDA’s whole genome sequencing analysis of that sample also confirmed that the E. coli O121 was closely related genetically to bacteria found in people who had become ill. The final piece of the puzzle was put into place, although the investigation continues to ensure that all contaminated product is off the market.

This was just one of the hundreds of voluntary recalls that the FDA facilitates every year. Going forward, the agency’s compliance and enforcement strategies, including recalls, will get even stronger with the recent establishment of a decision-making body of key senior leaders to identify timely and efficient measures to mitigate public health risks.

Laying the groundwork for a recall can be a complex and lengthy process, with only bits and pieces of information coming in at any one time. But tenacity, collaboration and a willingness to be proactive in protecting consumers, enabled the FDA, its federal, state, and local partners, and General Mills to quickly and efficiently work to recall a potentially dangerous product and keep even more people from becoming ill.

Stephen Ostroff, M.D., is FDA’s Deputy Commissioner for Foods and Veterinary Medicine

Kathleen Gensheimer, M.D., M.P.H., is the director of FDA’s Coordinated Outbreak Response and Evaluation (CORE) network