As the country faces yet another recall of lettuce due to possible E. coli O157:H7 contamination, it is apparent that federal and state health officials and the lettuce industry have not taken adequate measures to prevent contamination.

Professor Daniel Fung, a food microbiology professor at Kansas State University, has spent 30 years studying and teaching students about E. coli and other foodborne pathogens. In an interview with Channel 49 (Topeka, Kansas), Professor Fung states, “When this strain [E. coli O157:H7] occurs, it is very serious, because many people can get very sick and children can die.”

The interview of Professor Fung continues:

Professor Fung said no matter if the latest E.Coli outbreak reaches Kansans, consumers should be concerned.

”Every death is too many,” he said.

It isn’t his job to find out what caused this latest recall of Dole’s packaged lettuce. However, he teaches his students where the FDA should start looking.

“Make sure that the manure didn’t go into the field at the same time,” he said. “If you can control the water supply better, then you will have a better chance of controlling the micro-organisms.”

To watch the interview of Professor Fung, please click here.

If Professor Fung is correct—and we think he is—the E. coli-contamination problem is resolvable:

1. Lettuce and other leafy greens should not be grown near cattle ranches (this is being done) or in areas where there is frequent flooding (this is also being done).


2. Irrigation water should be frequently tested for E. coli O157:H7.


3. Farmers not complying with the above should be fined and/or face criminal charges.

Pritzker | Ruohonen is a leading E. coli litigation law firm. To contact an E. coli lawyer at the firm, please call toll-free at 1-888-377-8900 or submit the firm’s online consultation form.

The Step-by-Step Process for Tracing a Food Implicated in an E. coli Outbreak:

1. A person experiencing the symptoms of E. coli (watery and/or bloody diarrhea, abdominal cramps, nausea, fever, vomiting, and/or body aches) goes to the doctor. The doctor makes an initial diagnosis, and stool cultures from the patient are sent to a clinical laboratory.
2. Medical lab tests are done on the stool culture. If the presence of E. coli is determined by the local clinical lab, an isolate of that bacterial culture is sent to the state health department lab for further testing, including PFGE (pulse-field gel electrophoresis). The state health department lab sends the PFGE results electronically to the Centers for Disease Control and Prevention (CDC).
3. The DNA "fingerprint" (PFGE result) of the E. coli isolate is compared at CDC with other "fingerprint" samples. If is a match, CDC notifies - via an automated e-mail - the state health departments, along with the Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA).
4. When there are several isolates with the same PFGE pattern, state health departments investigate to identify a common exposure, such as a common food that was eaten. Local health department representatives, generally epidemiologists, use standard questionnaires to interview both sick and well persons. First, they want to find out where the sickened people ate, such as at home, a picnic, or a restaurant. Then they look for a common food that was eaten.
5. If health officials find a sample of suspected food, testing is done to determine if the food is contaminated with E. coli and, if so, the PFGE pattern of the E. coli. If the PFGE matches those of the outbreak victims, that food is considered the source of the outbreak.
6. If it is determined that the foodborne illness was due to a food item that was served at a public eating establishment, such as a restaurant, health officials interview the food workers. They use questionnaires to find out what and how foods were prepared. If there was a sick food worker on the job when sickened people ate at the restaurant, etc., health officials will get stool cultures from the food worker. If his or her PFGE matches those of the sickened people, health officials consider the worker to be the source of the contamination.
7. If food found at a restaurant tests positive for E. coli and the PFGE matches the outbreak pattern, that food is considered the source of the outbreak. Even if health officials do not find food that tests positive for E. coli, a restaurant can be found liable for any illness associated with eating its food.

If a common food is identified , federal health officials use trace-back techniques to determine where the food came from. If the food is produce, the goal is to find the field where it came from. If the food is meat, the goal is to find the animal it came from. The trace-back stage of the investigation is the responsibility of the FDA (produce) or USDA (meat).

8. Once the traceback investigation has determined the source of the outbreak, steps are taken to prevent further exposure or spread of the infection. For example, if the source is a specific food being distributed, a recall of that food will be implemented. If the source is an infected food worker, that person will be removed from any food-service duties until they have recovered and tested negative for that bacteria.

In recent years, uncovering and tracking foodborne outbreaks involving bacterial pathogens has become vastly easier with PulseNet. The following is from the CDC PulseNet site:

PulseNet is a national network of public health and food regulatory agency laboratories coordinated by the Centers for Disease Control and Prevention (CDC). The network consists of: state health departments, local health departments, and federal agencies (CDC, USDA/FSIS, FDA).

PulseNet participants perform standardized molecular subtyping (or “fingerprinting”) of foodborne disease-causing bacteria by pulsed-field gel electrophoresis (PFGE). PFGE can be used to distinguish strains of organisms such as Escherichia coli O157:H7, Salmonella, Shigella, Listeria, or Campylobacter at the DNA level. DNA “fingerprints,” or patterns, are submitted electronically to a dynamic database at the CDC. These databases are available on-demand to participants—this allows for rapid comparison of the patterns.

Pulsed Field Gel Electrophoresis (PFGE) is a methodology that digests bacterial DNA into fragments which can be run on gels, which produces unique patterns. Like human fingerprints, each bacteria and its offspring have a unique PFGE pattern. If two bacteria are found with an indistinguishable pattern, it is likely that they have a common source and may be part of an outbreak.

A national computer database of PFGE patterns is housed at CDC. States submit PFGE patterns of pathogens that have made people sick to the database over the Internet. The computer then automatically scans previously submitted patterns searching for matches, i.e., indistinguishable DNA fingerprint patterns of pathogens that have made other people sick. If a match is found, a signal is given to the submitter that duplicate patterns are present and where they came from, so that an investigation can begin to look for a common source.

PulseNet is an invaluable resource that identifies outbreaks that would have most likely gone unnoticed. In the 2006 E. coli outbreak linked to bagged, fresh spinach, state epidemiologists uncovered the outbreak using PulseNet technology and quickly alerted the CDC. Within a short period of time, the FDA issued a warning regarding fresh, bagged spinach that may have prevented many more illnesses and deaths.

Pulse-field gel electrophoresis (PFGE) is the DNA "fingerprinting" method that scientists use to determine the source of bacterial foodborne outbreaks.

How Does PFGE Work?

The DNA of the bacterial pathogen responsible for a foodborne illness is digested into pieces by reacting the isolated DNA with enzymes that are able to specifically break the DNA molecule into individual pieces. The digested DNA is placed at one end of the gel. A pulsing electric field applied across the gel drives the DNA pieces into the gel over a period of hours. The smallest pieces slip through the pores of the gel more quickly, so the pieces are separated as distinct bands in the gel, based on size. The resulting pattern of 30 to 50 bands, which resembles a bar code is the "fingerprint."

What are the Food Safety Implications of PFGE?

Like human fingerprints, each bacteria and its offspring have a unique PFGE pattern. If two bacteria are found with an indistinguishable pattern, it is likely that they have a common source and may be part of an outbreak. A national computer database of PFGE patterns is housed at CDC as part of PulseNet. States submit PFGE patterns of pathogens that have made people sick to the database over the Internet. The computer then automatically scans previously submitted patterns searching for matches, i.e., indistinguishable DNA fingerprint patterns of pathogens that have made other people sick. If a match is found, a signal is given to the submitter that duplicate patterns are present and where they came from, so that an investigation can begin to look for a common source.

What are the Legal Implications of PFGE?

For someone who has been diagnosed with E. coli to be considered part of an E. coli outbreak, the DNA fingerprint of the E. coli bacteria that sickened the person has to be indistinguishable from the DNA fingerprint of the E. coli bacteria that sickened at least one more person. If a food item can be found with the same DNA fingerprint, that food item is considered the source of the outbreak. This connecting of DNA fingerprints between people and food is used to establish legal liability. For example, if 2 or more people ate at a restaurant and contracted E. coli infections, and the DNA fingerprints of those 2 people and a food item at the restaurant were indistinguishable, the restaurant would be liable to the sickened people for all damages related to the E. coli infections, including illness that develop as a result of the E. coli infections, including hemolytic uremic syndrome (HUS).

Even if a food item is not found at the restaurant with the same DNA fingerprint as the bacteria that sickened outbreak victims, the restaurant can still be held liable to the sickened people. In a recent case, we represented people sickened at a restaurant in a situation where: 1. no food item was found with the same DNA fingerprint and 2. more than one food item could have been the vehicle for transmission of the foodborne pathogen. Even so, we negotiated a settlement with the restaurant, and our clients were fairly compensated.

To contact us, please call toll-free at 1-888-377-8900 or submit our online consultation form. Our law firm, Pritzker | Ruohonen has a national practice representing victims of foodborne illness, including E. coli.

An E. coli outbreak is an incident in which 2 or more cases of E. coli result from the same source. To determine if 2 or more people contracted E. coli from the same source, health officials conduct DNA fingerprinting of E. coli isolates from the victims' stool samples. Health officials then compare the DNA fingerprints, looking for similarities. E. coli victims sickened by genetically similar E. coli bacteria contracted the E. coli from the same source.

E. coli outbreaks are often foodborne. Food can cause E. coli outbreaks when the food is contaminated internally or becomes contaminated during harvesting, processing, or preparation. When there is a foodborne E. coli outbreak, public health scientists use epidemiological, microbiological, and trace-back technologies to control the outbreak and remove the food from the distribution channels.

In some cases, an E. coli outbreak is linked to a restaurant, deli, or other establishment that serves food. Even if the food product that caused the illnesses is not found, victims of the E. coli outbreak can pursue a claim against the eating establishment. In a recent foodborne illness case handled by our firm, health officials linked the illness to a restaurant but could not pinpoint the food that caused the illness. Epidemiological evidence pointed to the source of the outbreak being one of several possible food items. Even so, we obtained a settlement for our clients.

To contact an E. coli lawyer at Pritzker | Ruohonen, please call toll-free at 1-888-377-8900 or submit the firm's online consultation form.

FoodNet is a joint effort by the CDC, FDA, USDA, and state health departments to monitor trends in the occurence of foodborne illness. The CDC funds cooperative agreements with some state and local health departments to conduct population-based surveillance and research that go beyond the routine functions of health departments. There are currently sites in 10 states: California, Colorado, Connecticut, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon, and Tennessee.

The CDC FoodNet website lists the following as the objectives of the program:

• Determine the burden of foodborne illness in the United States
• Monitor trends in the burden of specific foodborne illness over time
• Attribute the burden of foodborne illness to specific foods and settings
• Develop and assess interventions to reduce the burden of foodborne illness

FoodNet monitors the occurrence of illness related to nine different pathogens: Campylobacter, Cyclospora, Cryptosporidium, E. coli (both O157:H7 and other strains of E. coli), Listeria monocytogenes, Salmonella, Shigella, Vibrio, and Yersinia enterocolitica. FoodNet also conducts hemolytic uremic syndrome (HUS) surveillance. HUS is an illness that can develop from an E. coli O157:H7 infection.

For each case of illness, FoodNet reviews the case and collects and analyzes strains. Special case-control studies are conducted across FoodNet sites in order to identify the major risk factors for sporadic illness, and community surveys are conducted to help determine the overall burden of foodborne illness.

The Center for Disease Control and Prevention (CDC) works with state and local health departments to conduct ongoing surveillance of cases of foodborne illness and to investigate disease outbreaks. The CDC uses both surveillance data and results of outbreak investigations to identify the factors responsible for illness so that immediate control measures can be taken and longer term prevention strategies can be developed. The CDC's role in measuring the success of interventions is to see whether they translate into reductions in the incidence of human cases of foodborne illness.

Chronology of CDC Involvement in an E. coli Outbreak

1. The first response in an E. coli outbreak is usually from the state or local health department.
2. If the outbreak warrants, the state health department will invite the CDC to participate in the investigation. This is warranted if an outbreak is very large or significant, is thought to involve an unusual pathogen or unexpected food vehicle, affects multiple states or countries, or preliminary investigations do not reveal a source.
3. The CDC, working with state and local health officials, combines laboratory diagnostic techniques and epidemiologic investigative methods to determine the causative agent of the illness, the food vehicle responsible for transmission, and the environmental factors that contributed to the outbreak.
4. If a food is identified as the source of illness, the CDC collaborates with the FDA or USDA on the investigation and control of the outbreak, based upon which agency regulates the suspected food.

In September of 2006 epidemiologists in Wisconsin identified several cases of E. coli O157:H7 that they suspected were associated with the consumption of fresh spinach. During this time, epidemiologists in Oregon noticed the same thing. The spinach-E. coli outbreak had begun. The following is a CDC-recount of events surrounding the spinach-E. coli outbreak of the fall of 2006 which sickened hundreds of people and resulted in at least 3 deaths:

On September 13, 2006, CDC officials were alerted by epidemiologists in Wisconsin and Oregon that fresh spinach was the suspected source of small clusters of Escherichia coli serotype O157:H7 infections in those states. On the same day, New Mexico epidemiologists contacted Wisconsin and Oregon epidemiologists about a cluster of E. coli O157:H7 infections in New Mexico associated with fresh spinach consumption. Wisconsin public health officials had first reported a cluster of E. coli O157:H7 infections to CDC on September 8. On September 12, CDC PulseNet had confirmed that the E. coli O157:H7 strains from infected patients in Wisconsin had matching pulsed-field gel electrophoresis (PFGE) patterns and identified the same pattern in patient isolates from other states. This report describes the joint investigation and outbreak-control measures undertaken by state public health officials, CDC, and the Food and Drug Administration (FDA). This investigation and additional case finding are ongoing.

As of September 26, a total of 183 persons infected with the outbreak strain of E. coli O157:H7 had been reported to CDC from 26 states (Figure 1). Among the ill persons, 95 (52%) were hospitalized, 29 (16%) had hemolytic uremic syndrome (HUS), and one person died. The deaths of two other patients possibly related to this outbreak are under investigation. Eighty-five percent of patients reported illness onset from August 19 to September 5 (Figure 2). Fresh spinach was identified as the source of the outbreak. One hundred twenty-three of 130 patients (95%) reported consuming uncooked fresh spinach during the 10 days before illness onset. In addition, E. coli O157:H7 with a PFGE pattern matching the outbreak strain has been isolated from three open packages of fresh spinach consumed by patients (one from New Mexico, one from Utah, and one from Pennsylvania).

On September 14, FDA advised consumers by press release and press conference to not eat bagged fresh spinach. On September 15, a California company that bags spinach under several brand names announced a voluntary recall of all fresh spinach-containing products. On September 16, FDA expanded its warning and advised consumers to not eat fresh spinach or fresh spinach-containing products. On September 21, FDA informed consumers that only spinach grown in three California counties (Monterey, San Benito, and Santa Clara) was implicated in the outbreak.

A confirmed case is defined as a culture-confirmed E. coli O157:H7 infection in a person residing in the United States, with illness onset from August 1 to the present (or, if date of onset is unknown, E. coli O157:H7 isolated from August 15 to the present) and a PFGE pattern identified by the XbaI restriction enzyme that matches the pattern of the outbreak strain. August 1 was selected as the earliest illness onset date in the case definition to ensure that the earliest cases in the outbreak were identified and investigated. However, the first six confirmed cases (with illness onsets during August 2--15) were in persons who did not report fresh spinach consumption during the week before illness onset. The first date that illness onset was reported by a person who recently consumed fresh spinach was August 19.

Infections with this outbreak strain of E. coli O157:H7 (one of 3,520 unique E. coli O157:H7 strains reported to CDC PulseNet since 1996) have been reported sporadically to CDC PulseNet since 2003 (an average of 21 cases per year during 2003--2005). This finding suggests the occasional presence of this strain in the environment and food supply; however, it has not been associated with a recognized outbreak in the past.

The time from illness onset to confirmation that a case of E. coli O157:H7 is part of an outbreak is typically 2--3 weeks, including the time required for an infected person to seek medical care and for health-care providers and public health officials to obtain a culture, transfer the bacterial culture to a public health laboratory, perform PFGE testing, and submit the PFGE pattern into the national database at CDC. In this outbreak, the average time from illness onset to PFGE pattern submission to the national database at CDC has been 15 days; additional information is available at http://www.cdc.gov/foodborne/ecolispinach/reportingtimeline.htm.

Parallel laboratory and epidemiologic investigations were crucial in identifying the source of this outbreak. Timely PFGE testing by state public health laboratories, PFGE pattern submission by states to CDC PulseNet, and analysis of PFGE patterns in the CDC PulseNet national database resulted in rapid detection of the outbreak. Concurrent collection of case exposure information by epidemiologists in affected states and sharing of exposure information among states and CDC led to rapid identification of the suspected food source and public health action.

Source: “Ongoing Multistate Outbreak of Escherichia coli serotype O157:H7 Infections Associated with Consumption of Fresh Spinach --- United States, September 2006,” Morbidity and Mortality Weekly Report, September 29, 2006, Vol. 55, No. 38:1045-1046.

For information about E. coli, please see the following:

• E. coli symptoms


• E. coli treatment


• E. coli Lawsuit


• E. coli Lawyer


• Hemolytic Uremic Syndrome (HUS)

Pritzker | Ruohonen has a national practice and represents E. coli victims throughout the United States. To contact the firm, please call toll-free at 1-888-377-8900 or submit the online contact form.

Each year hundreds of people are sickened by E. coli and about 60 die. Until fairly recently, it was difficult tracking an E. coli outbreak. The Centers for Disease control (CDC) now has a system of genetic fingerprinting for E. coli bacteria (and other foodborne bacteria) called PulseNET. Here is the CDC explaination of PulseNET:

PulseNet is a national network of public health and food regulatory agency laboratories coordinated by the Centers for Disease Control and Prevention (CDC). The network consists of: state health departments, local health departments, and federal agencies (CDC, USDA/FSIS, FDA).

PulseNet participants perform standardized molecular subtyping (or “fingerprinting”) of foodborne disease-causing bacteria by pulsed-field gel electrophoresis (PFGE). PFGE can be used to distinguish strains of organisms such as Escherichia coli O157:H7 (E. coli O157:H7), Salmonella, Shigella, Listeria, or Campylobacter at the DNA level. DNA “fingerprints,” or patterns, are submitted electronically to a dynamic database at the CDC. These databases are available on-demand to participants—this allows for rapid comparison of the patterns.

If someone goes to the doctor with symptoms of E. coli, a sample of the stool may be tested for E. coli bacteria. If E. coli bacteria is found, further testing may be needed to determine if the E. coli bacteria is E. coli O157:H7. If the stool samples test positive for E. coli O157:H7 or another virulent strain of E. coli bacteria, a culture of the E. coli bacteria may be sent to the CDC for genetic fingerprinting as part of the PulseNET system. Not every case of E. coli O157:H7 has this testing done. This is one reason why it is imperative that anyone diagnosed with E. coli contacts a lawyer immediately. At Pritzker | Ruohonen, we have a process for getting the needed testing done.

Each E. coli outbreak involves a genetically-unique E. coli bacteria. This means that the genetic fingerprint of the E. coli O157:H7 bacteria for one outbreak is genetically unique from the E. coli O157:H7 bacteria of a different outbreak. For example, in the fall of 2006, there were two E. coli outbreaks involving Mexican fast food restaurants, Taco Bell and Taco Johns. The CDC knew that these outbreaks were two, unrelated outbreaks because the genetic fingerprint of the E. coli O157:H7 involved in the Taco Bell outbreak was different from the E. coli O157:H7 in the Taco Johns outbreak.

Once the PulseNET system identifies an outbreak (generally two or more cases of E. coli with identical genetic fingerprints), epidemiologists interview the people who contracted the E. coli infections to try determine the source of the outbreak. Obviously, if the cases are children, people who are too sick to be interviewed, or people have died, family members and others are interviewed.

Pritzker | Ruohonen has a national practice and represents E. coli victims throughout the United States. To contact the firm, please call toll-free at 1-888-377-8900 or submit the online contact form.