E. coli in Lettuce - A Study of Yuma Lettuce Production, 2006

With 29 confirmed and probable cases of E. coli O145 infection linked to Freshway brand romaine lettuce, investigators continue their search to confirm the lettuce's place of origin.   A possible answer is the farms in Yuma, Arizona:  "A potential location has been identified in Yuma," Kurt Nolte, Yuma County Cooperative Extension director and agriculture agent, said Friday.

The long history connecting leafy greens to outbreaks of pathogenic E. coli is well documented.  The potential for contamination of lettuce from the Yuma area was investigated previously.  At a conference in November, 2006, following on the heels of the Dole spinach outbreak, Jorge M. Fonseca, of the University of Arizona, Yuma Agricultural Center, Department of Plant Sciences, gave this informative presentation.

Among the issues looked at- soil quality; water source; wildlife intrusion; and proximity to cattle farms.  Mr. Fonseca noted that very few animals were noted in Yuma lettuce fields, with the exception of migratory birds.   It was also reported that the farms draw their water from the Colorado River, almost exclusively.  At the time of the report cattle farming in the area was apparently limited, although domestic cattle could be found in the area.

FDA to announce new produce safety rules

Largely due to a string of E. coli O157:H7 outbreaks linked to lettuce and other leafy greens, the FDA will soon announce new rules (as opposed to voluntary recommendations) for the production and packing of fresh produce.  See FDA Produce Rule Announcement.  The new rules will set enforceable standards for fresh produce safety at the farm and packing house.  The purpose of the proposed rule:

is to reduce the risk of illness associated with contaminated fresh produce. The proposed rule will be based on prevention-oriented public health principles and incorporate what we have learned in the past decade since the agency issued general good agricultural practice guidelines entitled “Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables” (GAPs Guide). The prtoposed rule also will reflect comments received on the agency's 1998 update of its GAPs guide and its July 2009 draft commodity specific guidances for tomatoes, leafy greens, and melons. Although the proposed rule will be based on recommendations that are included in the GAPs guide, it does not make the entire guidance mandatory. FDA’s proposed rule would, however, set out clear standards for implementation of modern preventive controls.

One positive thing to come from the produce-related outbreaks of the past several years is a lot of data--about, among other things,  the importance of traceability, how and why outbreaks happen, and measures to take at the farm and processing level to reduce the potential for proliferation of disease causing bacteria. 

Here are several accounts of severe foodpoisoning illnesses suffered by produce outbreak victims:

Kelly Cobb--developed hemolytic uremic syndrome (HUS) after consuming E. coli O157:H7 contaminated romaine lettuce.

Heather Whybrew--hospitalized three weeks after consuming E. coli O157:H7 contaminated romaine lettuce.

Regan Erickson--developed HUS after consuming E. coli O157:H7 contaminated Dole baby spinach.

Ashley Armstrong--developed HUS after consuming E. coli O157:H7 contaminated Dole baby spinach.

June Dunning, Betty Howard, and Ruby Trautz--women who died after consuming E. coli-contaminated Dole baby spinach. 

USDA-FDA joint statement on produce safety

Yesterday, the USDA and FDA released a joint statement on their intent to coordinate efforts to achieve better produce safety.  See Salinas Valley, Leafy Green Vegetables, and E. coli for a description and summary of the problem.  The joint statement reads as follows:

The U.S. Department of Agriculture (USDA) and the Food and Drug Administration are working together to achieve the goals of enhancing the safety and quality of fresh produce in ways that take into account the wide diversity of farming operations. We are committed to leveraging the expertise of our partner agencies and working together to ensure that our current produce safety and quality activities are complementary and consistent. While USDA’s Agricultural Marketing Service (AMS) is in the midst of evaluating a proposed marketing agreement for the leafy green industry, the FDA is currently developing a proposed produce safety regulation. It is our expectation that these products will take into account the diverse nature of farming operations and that any marketing agreement would conform to any regulations that may be promulgated by FDA.

The success of these efforts depends on the feedback and comments we receive from growers and other produce safety stakeholders. AMS will continue to review the comments that have been submitted to USDA on the proposed marketing agreement. To further inform its planned rulemaking, the FDA is announcing today the establishment of a docket to receive information about current practices and conditions for the production and packing of fresh produce and practical approaches to improving produce safety. The FDA will work with AMS to have the testimony from the AMS hearings placed in the FDA docket for consideration by the FDA. The FDA encourages all interested persons to submit information they believe will inform the development of safety standards for fresh produce at the farm and packing house, as well as strategies and cooperative efforts to ensure compliance with those standards.

Salinas Valley, Leafy Green Vegetables, and E. coli

On February 5, 2004, the FDA wrote a letter to the lettuce and tomato industries to voice its concern about the frequent outbreaks linked to those products. In the letter, the FDA counted 14 such outbreaks since 1996 that it had investigated. Among other things, the letter stated:

In view of continuing outbreaks associated with fresh lettuce and fresh tomatoes, we strongly encourage firms in your industries to review their current operations in light of the agency’s guidance for minimizing microbial food safety hazards in fresh lettuce and fresh tomatoes, as well as other available information regarding pathogen reduction or elimination on fresh produce. We further encourage these firms to consider modifying their operations accordingly, to ensure that they are taking the appropriate measures to provide a safe product to the consumer. Since the available information concerning some of the recent outbreaks does not definitively identify the point of origin of the contamination, we recommend that firms from the farm level through the distribution level undertake these steps.

On September 30, 2005, a year and a half after the FDA’s 2004 letter to the lettuce industry, the Minnesota Department of Health issued a press release stating that 11 Minnesota residents had been infected by E. coli O157:H7 from contaminated Dole romaine lettuce. Two days later, the FDA issued a nationwide public health alert regarding Dole pre-packaged salads. Further investigation indicated that 22,321 cases of potentially contaminated Dole romaine lettuce had been sent to market from a processing facility in central California. Ultimately, at least 32 people were sickened in the outbreak.

One month after the 2005 Dole lettuce outbreak, the FDA wrote the industry again. The November 4, 2005 letter began as follows: “This letter is intended to make you aware of the Food and Drug Administration's (FDA's) serious concern with the continuing outbreaks of foodborne illness associated with the consumption of fresh and fresh-cut lettuce and other leafy greens.” The letter continued:

FDA is aware of 18 outbreaks of foodborne illness since 1995 caused by Escherichia coli O157:H7 for which fresh or fresh-cut lettuce was implicated as the outbreak vehicle. In one additional case, fresh-cut spinach was implicated. These 19 outbreaks account for approximately 409 reported cases of illness and two deaths. Although tracebacks to growers were not completed in all 19 outbreak investigations, completed traceback investigations of eight of the outbreaks associated with lettuce and spinach, including the most recent lettuce outbreak in Minnesota, were traced back to Salinas, California.

After pointing its finger steadily at central California, the FDA closed its 2005 letter to the industry by encouraging action to correct the problems within the industry, specifically outlining certain steps that the industry needed to take.

September 2006 changed everything. It was the month that the word “outbreak” truly became part of everybody’s vocabulary. It was the month that E. coli O157:H7-contaminated spinach caused 204 confirmed illnesses nationally; left 102 people hospitalized, 31 with hemolytic uremic syndrome (HUS); and caused three deaths . . . at least by the CDC’s official count. Among the dead were an elderly Wisconsin resident; a two-year-old Idaho boy named Kyle Algood; 81-year-old Ruby Trautz; 86-year-old June Dunning; and 83-year-old Betty Howard. And for those who survived their acute HUS illnesses, many will require a life-time of medical care, including kidney transplants, that may cost well over one hundred million dollars in the end accounting.

The large-scale investigation that followed, complete with an armed FBI raid, ultimately proved that the spinach had been grown, packed, processed, and bagged in the Salinas Valley, California.

On the heels of this devastating outbreak, fresh spinach sales stopped entirely for almost two weeks while the nation was gripped by a panic bigger than any it had before seen with respect to a single food product. Sales over the next several months plummeted from pre-outbreak levels. Ultimately, spinach sales did not reach pre-recall levels until the end of January 2008.

But the heavy impact of California failures wasn’t over yet, not even for the year 2006. Before the year ended, at least two more major lettuce-associated outbreaks hit: one at Taco John’s restaurants in the Midwest, and one at Taco Bell restaurants in the East; both as a result of contaminated iceburg lettuce grown in California. The Taco John’s outbreak left 81 people ill, 26 hospitalized and two with HUS; and the Taco Bell outbreak caused 71 confirmed illnesses, 53 hospitalizations, and eight cases of HUS. Again, traceback investigation in both outbreaks proved that the lettuce had gone to Taco John from the Bakersfield area and to Taco Bell from near Huron in the Central Valley.

Out the other end of this vortex came the Leafy Greens Marketing Agreement (LGMA). The LGMA website, states as follows:

In 2007 California farmers came together to raise the bar for food safety. As a result the California Leafy Green Products Handler Marketing Agreement (LGMA) was formed. Members of the LGMA are working collaboratively to protect public health by reducing potential sources of contamination in California-grown leafy greens.

To date nearly 120 handlers, representing approximately 99% of the volume of California leafy greens, have joined the LGMA. These companies have committed themselves to sell products grown in compliance with the food safety practices accepted by the LGMA board. LGMA membership requires verification of compliance with the accepted food safety practices through mandatory government audits. These food safety practices were developed by university and industry scientists, food safety experts and farmers, shippers and processors. California leafy greens are now grown under a unique system that has become a model for leafy green growers in other states.

It is in everybody’s interests for Salinas Valley to produce a safer product. The area is one of the largest exporters of fresh produce anywhere, accounting for 570 million pounds of the world’s produce exports every year. http://www.salinaschamber.com/ag_industry.asp. Salinas Valley produce goes to consumers across the country, as well as many of the world’s other major economies, including Canada, Japan, Hong Kong, Taiwan, Mexico, and the European Union.

Critical questions remain unanswered on the efficacy of the LGMA, and Salinas area processors’ efforts to implement its principles. Has this 3.8 billion dollar a year agricultural Mecca come up with any solutions to its complex problems? How well have the LGMA, the many lawsuits that individual producers have faced, and the FDA-led governmental pressure really worked? If not, why not? And what is the price of failure? More to come on this major public health issue.

The Uglier Side of Lettuce

After a frightful two-year stretch in 2005 and 2006 that included two Dole spinach/lettuce outbreaks due to E. coli O157:H7 contamination, the resurgence of ground beef as a leading vector in E. coli cases must have caused lettuce to feel a little left out.  The last month, with the announcement of a major national outbreak linked to shredded lettuce and yesterday's announcement of a three-state outbreak also likely linked to lettuce, feels a bit like the wakening of a very mean jolly green giant. 

Here's a brief look at E. coli O157:H7 outbreaks linked to lettuce and other leafy greens over the past decade (or a little longer): 

- in October 2003, thirteen residents of a California retirement home were sickened, and two people died, after eating E. coli-contaminated, pre-washed spinach;

- in September 2003, nearly forty patrons of a California restaurant chain fell ill after eating salads prepared with bagged, pre-washed lettuce; and

- in July 2002, over fifty young women fell ill with E. coli O157:H7 at a dance camp after eating “pre-washed” lettuce, leaving several hospitalized and one with life-long kidney damage.

Here are a few more examples:

- Aug. 1993  E. coli O157:H7 outbreak linked to a salad bar; 53 reported cases in Washington State

- July 1995  Lettuce (leafy green; red; romaine) E. coli O157:H7; 70 reported cases in Montana

- Sept. 1995  Lettuce (romaine) E. coli O157:H7; 20 reported cases in Idaho

- Sept. 1995  Lettuce (iceberg) E. coli O157:H7; 30 reported cases in Maine

- Oct. 1995  Lettuce (iceberg; unconfirmed) E. coli O157:H7; 11 reported cases in Ohio

- May-June 1996  Lettuce (mesclun; red leaf) E. coli O157:H7; 61 reported cases in Connecticut, Illinois, and New York

- May 1998  Salad E. coli O157:H7; two reported cases in California

- Feb.-Mar. 1999  Lettuce (iceberg) E. coli O157:H7; 72 reported cases in Nebraska

- Apr. 2004  Spinach E. coli O157:H7; 16 reported cases in California

- Sep. 2005  Lettuce (romaine) E. coli O157:H7; 32 reported cases in Minnesota, Wisconsin, and Oregon

But we all know that the list does not end there. E. coli O21:H19 nearly killed two women at a Wendy's in Utah.  Also Taco Bell and Taco John's in late 2006.

2008 saw E. coli outbreaks linked to lettuce in Michigan and the State of Washington - Spinach too in Oregon.

National Salmonella Typhimurium Outbreak Linked to Lettuce?

Lynne Terry of The Oregonian reported this afternoon that Oregon health authorities have announced a suspected link between 124 Salmonella Typhimurium illnesses nationally and lettuce.  The illnesses began appearing in mid-July and trailed off about a month later.  Seven Oregon residents fell ill between Aug. 4 to 16, including three in the Portland metro area.

One of the Oregon residents who became ill suffered a particularly severe illness and was hospitalized for several weeks.  Doctors removed a portion of her gastrointestinal tract, which had become necrotic and non-functional as a result of her severe infection with Salmonella Typhimurium.  We represent this unfortunate woman, and are working hard to discover for her what the ultimate source of her illness was.

This would certainly not be the first time that contaminated lettuce or other leafy greens caused an outbreak of severe illnesses.  In addition to the infamous Dole spinach E. coli outbreak in 2006, here are a few others:

November-December 2006 - Taco Bell and Taco Johns E. coli shredded lettuce sickened hundreds in Mid-west and East

June 2005 - 30 sickened in three states by E. coli-tainted Dole Lettuce

October 2003 - thirteen residents of a California retirement home were sickened, and two people died, after eating E. coli-contaminated, pre-washed spinach

September 2003 - nearly forty patrons of a California restaurant chain fell ill after eating salads prepared with bagged, pre-washed lettuce

July 2002 - over fifty young women fell ill with E. coli O157:H7 at a dance camp after eating “pre-washed” lettuce, leaving several hospitalized and one with life-long kidney damage

August 1993 - E. coli O157:H7 outbreak linked to a salad bar; 53 reported cases in Washington State

July 1995 - Lettuce (leafy green; red; romaine) E. coli O157:H7; 70 reported cases in Montana

September 1995 - Lettuce (romaine) E. coli O157:H7; 20 reported cases in Idaho

September 1995 - Lettuce (iceberg) E. coli O157:H7; 30 reported cases in Maine

October 1995 - Lettuce (iceberg; unconfirmed) E. coli O157:H7; 11 reported cases in Ohio

May-June 1996 - Lettuce (mesclun; red leaf) E. coli O157:H7; 61 reported cases in Connecticut, Illinois, and New York

May 1998 - Salad E. coli O157:H7; two reported cases in California

February.-March 1999 - Lettuce (iceberg) E. coli O157:H7; 72 reported cases in Nebraska

July-August 2002 - Lettuce (romaine) E. coli O157:H7; 29 reported cases in Washington and Idaho

October 2003-May 2004 - Lettuce (mixed salad) E. coli O157:H7; 57 reported cases in California

April 2004 - Spinach E. coli O157:H7; 16 reported cases in California

September 2005 - Lettuce (romaine) E. coli O157:H7; 32 reported cases in Minnesota, Wisconsin, and Oregon

Lettuce recalled for Salmonella contamination

Tanimura & Antle, Inc. recalled one lot of romaine lettuce for Salmonella contamination yesterday after a Wisconsin Department of Agriculture test came back positive for the bacterium. According to a press release on the Tanimura & Antle website:

Within hours of being notified yesterday, Tanimura & Antle, Inc. traced back the entire lot of romaine and advised all customers who received the recalled product of the test result. Tanimura & Antle, Inc. has instructed these customers to destroy the product. Although the recalled product is past its shelf life, the company is issuing this voluntary recall out of an abundance of caution to ensure that any product purchased by consumers will also be destroyed. Consumers who have purchased the recalled romaine as described above should not consume it, and should destroy the product.

The cartons of bulk or wrapped romaine being recalled are marked with the lot code 531380 and were harvested June 25 - July 2. This recall includes only this single lot of romaine; no other products are involved.

The recalled romaine was sold to retail, wholesale and food service outlets in Canada, Puerto Rico and the following 29 states: Alabama, Arkansas, California, Colorado, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kentucky, Texas, Massachusetts, Louisiana, Pennsylvania, Tennessee, North Carolina,

Lettuce field - salmonella recall

 Michigan, Missouri, Nebraska, New Hampshire, New Mexico, Nevada, Ohio, Oregon, Utah, Virginia, Wisconsin, Wyoming.

Produce can become contaminated with Salmonella in a number of ways. Contaminated farm equipment can contaminate produce if it comes into direct contact with raw untreated manure, untreated compost, contaminated water, animals that shed Salmonella in their feces, or with people who somehow become contaminated. Fresh produce exposed to flood waters that carry Salmonella can become contaminated pre-harvest. Runoff water that could potentially carry Salmonella should be diverted from fields growing fresh produce and should not be used for irrigation. 

Fresh produce fields in rural areas next to wetlands or wildlands are particularly susceptible to exposure by wild animals such as deer and wild boars that harbor Salmonella and other pathogenic bacteria. Domestic animals and livestock that make their way into fields can also contaminate fresh produce, as can field workers who are shedding Salmonella in their stool if they do not use proper hand-washing techniques, or if proper toilet facilities are not available to them in the fields where they work.  

Produce E. coli Problems of a Different Variety

Most of the time when we're writing about, reading about, or representing people for illnesses suffered in an E. coli O157:H7 outbreak related to produce, we're looking at things retrospectively.  An outbreak of E. coli O157:H7 happened, we know it was linked to lettuce, spinach, or some other type of fresh, raw produce, but we are sometimes left digging for answers as to how the E. coli got onto (or even into) the lettuce or spinach leaves.

For once, we may have a glimpse, albeit a narrow one, of how these lettuce and spinach E. coli outbreaks actually get started.  The attached is an "incident alert" from the Food Safety and Defense organization.  It involves a modern day Bo Peep who apparently forgot what fences mean (actually, it's a little unclear who owned the property).  The sheepherders allowed their herd to invade a carrot growing field where the carrot behemoth Grimmway was actively growing carrots.

Sounds innocent enough, right?  I mean, they're just sheep, and they just wanted to eat a few carrots.  Probably just the tops of the carrots that nobody eats anyways.

Well, sheep are ruminant animals well-known to harbor E. coli O157:H7, and other pathogenic bacteria, in their gastrointestinal tracts.  I know nothing about any "problems" (i.e. linked e. coli illnesses) . . . yet.  Hey, just an aside here, but what's up with California lettuce?  Anybody know anything that we don't?

Listeria found in lettuce

Listeria monocytogenes, a potentially deadly foodborne pathogen, has been found in lettuce samples, according to a story published at monstersandcritics.com
WKMG-TV in Orlando reported Saturday that Listeria bacteria has been linked to lettuce imported from California and sold at a Fresh Market store. Store officials said late Friday the lettuce has been pulled and no reports of illness had been made.

"We will continue to monitor the situation to ensure our stores are taking all necessary precautions," Fresh Market said in a press statement.
Listeria monocytogenes (Listeria) is a pathogenic (disease-causing) bacterium that is food borne and causes an illness called listeriosis. It is frequently overlooked as a possible cause of illness due to its unique growth capabilities. First, it is somewhat difficult for laboratories to grow, and when they do so, Listeria can be confused with common harmless contaminants and disregarded. Second, most bacteria grow poorly when temperatures fall below 40°F, while Listeria survives in temperatures from below freezing (20°F) to body temperature and it grows best at 0°F to 50°F, including the temperature range that we use for refrigeration. As a result, Listeria may be transmitted in ready-to-eat foods that have been kept properly refrigerated. Its ability to grow in such diverse environments is just one of the many challenges presented by this dangerous bacterium.

It is estimated that Listeria causes approximately 1,600 cases of listeriosis annually, resulting in 415 deaths.

Listeriosis is the disease caused by Listeria monocytogenes. It is acquired by the ingestion of contaminated foods. Certain groups of individuals are at great risk for listeriosis. These are pregnant women (and their unborn children) and immunocompromised persons (e.g., transplant recipients). Among infants, listeriosis occurs when the infection is transmitted from the mother, either through the placenta or during the birthing process. These host factors, along with the amount of bacteria ingested and the virulence of the strain, determine the risk of disease.

Listeria can invade the body through a normal and intact gastrointestinal tract. Once in the body Listeria bacteria can travel through the blood stream, but are often found inside cells (they are "intracellular" pathogens). Listeria can co-opt the cell's machinery to its own advantage by manipulating the host cell genes, and then move directly from cell-to-cell, avoiding many of the host's defense mechanisms. The bacteria also produce toxins that damages cells.

For unknown reasons, in immune-deficient hosts Listeria invades and grows best in the central nervous system, causing meningitis and/or encephalitis (brain infection). In pregnant women, the fetus is most heavily infected, leading to spontaneous abortion, stillbirths, or sepsis in infancy.

Tests show Nunes lettuce OK, but Mexico bans U.S. imports

Foxy lettuceThe Monterey Herald reports that Mexico is banning U.S. imports. More countries to follow?

Mexico's Department of Health announced Monday that the country's 105 ports of entry would block all U.S. lettuce from coming through the border as a result of Nunes Co.'s precautionary recall.

The family-run company recalled the lettuce after water from a reservoir at one of its grower's fields tested positive for generic E.coli, many harmless strains of which live in human intestines.

But on Tuesday, further tests of the recalled lettuce showed that the E.coli in the irrigation water was not the 0157:H7 strain, the form of the bacteria responsible for the outbreak linked to spinach that killed three people and sickened 199 others.

FDA Statement on Nunes Lettuce Recall

Foxy lettuce recallOn October 8, 2006, the Food and Drug Administration (FDA) became aware that The Nunes Company, Inc., of Salinas, California initiated a voluntary recall of green leaf lettuce distributed under the Foxy brand.  The company reported to FDA that it initiated the recall because of E.coli contamination of water used to irrigate the lettuce plants in the field during growing. At this time, there has been no determination of whether the E. coli found is O157:H7—the highly infectious type that can cause life-threatening foodborne illness in humans—or the more common, generally harmless strains of E. coli that usually do not cause disease. Further, there has been no known human illness linked to this recall.

Based on current information about the scope of this E. coli contamination, FDA views the firm's prompt action as commendable, because it is better to be cautious than to potentially put consumers at risk of contracting a serious foodborne illness. As FDA becomes aware of additional information about the contamination of the water supply that triggered the current voluntary recall, including the results of additional ongoing tests, the agency will make this information available to the public immediately.