Category: food poisoning

Investigators Need A Break In St. Louis E. coli O157:H7 Outbreak

Local, state and federal investigators are scratching their heads and hoping for a break as they try to identify the source of an outbreak of E. coli O157:H7 that has sickened at least 26 people in and around St. Louis, Missouri since October 25th. At least 19 outbreak victims have been hospitalized.

According to the Washington Post, the outbreak victims range in age from 1 to 94, and live in St. Louis city and four surrounding counties – St. Louis, Jefferson and St. Charles counties in Missouri, and St. Clair county in Illinois. The Illinois Department of Public Health acknowledged on October 28th that it was investigating a single illness in St. Clair County that might be linked to the Missouri outbreak.

The Missouri Department of Health and Senior Services is testing samples from an additional 25 suspect cases as part of the investigation into the outbreak, which appears to be linked to food sold from supermarket salad bars. At least some of the suspect salad bar components were supplied by distributors or processors outside of the state of Missouri, and FDA has been called in to assist in the inspection of the individual links in the distribution chain.

Initial patient interviews appeared to point to Schnucks Markets, Inc. salad bars as a common link. Schnucks is a regional supermarket chain headquartered in St. Louis, with Schnucks stores located in Missouri, Illinois, Indiana, and Iowa, and Logli/Hilander stores located in Rockford, Illinois and Janesville, Wisconsin.

Based on the initial information obtained from patients, Schnucks removed certain items from all of its salad bars, and replaced the items with products obtained from other suppliers. None of the items sampled so far from Schnucks salad bars or from the homes of patients have yielded E. coli.

After an additional round of patient interviews, a further 38 food samples have been collected from five Schnucks stores and submitted to the State lab for testing. These new samples include Bistro Salad Dressing, broccoli florets, deviled eggs, diced hard-boiled eggs, honey Dijon dressing, Italian dressing, pineapple chunks, red wine vinaigrette, shredded carrots, shredded radishes, shredded zucchini, and sliced red onions. In addition, six packaged salads that contain salad bar ingredients were submitted for analysis: Bistro Chopped Salad, Fresco House Salad, Fried Chicken Salad, Garden Salad, Italian Salad, and Turkey Cobb Salad.

The U.S. Centers for Disease Control and Prevention (CDC) has been called upon to assist in the epidemiological investigation, and is carrying out a case control study. The study will compare foods eaten by confirmed outbreak patients with foods consumed by a control group of healthy individuals living in the same area. With judicious questioning – and with some luck – the case control study might be successful in identifying one or more probable food sources for the outbreak.

Salad bar-related outbreaks can be especially difficult to trace to a source, due to the sheer number of different items present, and the potential for cross-contamination from serving utensils or the dropping of one salad bar item into another. Small salad ingredients, such as sliced vegetables, cherry tomatoes, and sprouts are especially susceptible to landing in the wrong bin. And people often don’t remember every vegetable or garnish that they selected.

Another complication in this outbreak investigation is the short shelf life of salad ingredients. The contaminated component may no longer be in the distribution chain. The longer it takes for a possible food to be identified via patient interviews and the case control study, the less likely it becomes that the contaminated food will be identified.

The State has not provided any time-related breakdown of the reported cases, so it’s difficult to tell whether or not the outbreak has reached its peak. Consumers in the St. Louis metropolitan area and surrounding counties should be especially careful in purchasing and handling salad items while this outbreak continues.

Public health officials in Missouri are urging anyone experiencing gastrointestinal symptoms, such as severe stomach cramps, diarrhea or nausea to seek medical attention.

Fresh Basil Suspected In Norway Shigella Outbreak

Fresh basil imported from Israel is the prime suspect in an outbreak of shigellosis, according to Norway’s Food Safety Authority (NFSA).

On October 10th, NFSA announced that several residents of Tromsø were suffering from shigellosis after becoming infected with Shigella sonnei – a microbe that usually is transmitted through contaminated water or food. As of today (November 1st), 46 outbreak cases have been confirmed – 42 in Tromsø and 4 in Østfold.

Most of the illnesses were reported in early October, with the last onset date having been recorded in mid-October.

Shigella outbreak onset dates

When interviewed, 36 of the outbreak patients reported having eaten pesto, and an additional three victims said that they had been served fresh basil – an ingredient in pesto. Patient interviews pointed to pesto made by a Tromsø catering company as a possible source of the infections.

Basil imported from Israel by Bama and supplied to the Tromsø company was used to make the pesto. Bama also supplied basil from the same batch to an Østfold restaurant where three of the four Østfold outbreak victims had eaten a few days before becoming ill.

Based on the epidemiological and tracing results, Bama has halted all sales of Israeli basil until further notice. Basil has a short shelf life, and the shipment that was implicated in this shigellosis outbreak is no longer in the marketplace.

Pine Nuts From Turkey Behind New Salmonella Outbreak

Pine nuts imported from Turkey by Sunrise Commodities (Englewood Cliffs, NJ) and sold in Wegmans supermarkets have been identified as the source of a strain of Salmonella Enteritidis that has infected 42 people in six US states.

CDC reports that the illnesses, which began on August 20, 2011, have been reported in Arizona (1), Maryland (1), New Jersey (2), New York (26), Pennsylvania (8) and Virginia (4). Two people were hospitalized.

Sixty-three percent (63%) of the 30 outbreak victims for whom information is available reported having eaten Turkish pine nuts, or products containing them, during the week before they became ill. Among the prepared foods identified as containing the contaminated pine nuts were Caprese salad or asparagus with pine nuts, sold at Wegmans stores. The CDC report is unclear whether these prepared foods were purchased ready-made from Wegmans stores, or whether they were home-prepared using pine nuts purchased at Wegmans.

The Salmonella Enteritidis outbreak strain was recovered by the Virginia Division of Consolidated Laboratory Services from Turkish pine nuts purchased from a Wegmans bulk bin and collected from a patient’s home, and from samples of Turkish pine nuts obtained directly from a Wegmans store. New York found Salmonella Enteritidis in two separate samples of homemade pesto containing the implicated pine nuts, as well as from a Wegmans store in that state and from pine nuts collected from a New York patient’s home. The Salmonella recovered from the pesto samples is identical to the outbreak strain.

Today, Wegmans Food Markets Inc. (Rochester, NY) recalled approximately 5,000 pounds of Turkish Pine Nuts sold in the bulk food departments of Wegmans stores in New York, Pennsylvania, New Jersey, Virginia and Maryland between July 1, and October 18, 2011.

Pine nuts have a fairly long shelf life, and may linger in consumers’ homes – either plain or as an ingredient in a pesto or prepared meal – for a long time after the retail recall is complete. CDC offers the following advice:

  • Consumers should check their homes, including refrigerators and freezers, for Turkish pine nuts purchased from bulk bins at Wegmans stores between July 1, 2011 and October 18, 2011 and not eat them. Consumers should also not eat any foods prepared with the recalled product, including pesto, salads, and baked goods.
  • Restaurants and food service operators should not serve the recalled product.
  • Consumers, retailers, and others who have any of the recalled product should dispose of it in a closed plastic bag placed in a sealed trash can. This will prevent people or animals from eating it.
  • Persons who think they might have become ill from eating possibly contaminated recalled products should consult their health care providers. Infants, older adults, and persons with impaired immune systems are more likely than others to develop severe illness.