The Salmonella Outbreak of 2008-2009, Research Paper Example

Abstract

Spanning the years 2008 to 2009, a multistate outbreak of salmonella infections was linked to several brands of peanut butter available throughout the United States. The Centers for Disease Control (CDC) was at the forefront of tracking the spread of the outbreak and tracing the source of the contamination to the Peanut Corporation of America (PCA). At the core of the CDC investigation was the PulseNet system, a computer-linked network of laboratories that uses DNA to identify and “fingerprint” bacteria to combat foodborne illnesses. In 2014 a federal jury convicted the former owner of PCA on conspiracy can other charges related to the salmonella outbreak. The following paper follows the timeline of events from the initial outbreak to the subsequent trial, and examines the failures and successes of the nation’s food-related infrastructure and legal system as it responded to the outbreak.

Beginning in late 2008 and continuing into early 2009 an outbreak of Salmonella Typhimurium (hereafter referred to as Salmonella) was identified in states across the U.S., and reports of illness and death mounted quickly. The Centers for Disease Control (CDC) in coordination with the Food and Drug Administration (FDA) began to compile these reports and to mount a joint investigation into the source of the outbreak. By January 2009 several products containing peanut butter and other peanut products were identified as carries of the pathogen; among the first products named by the CDC and FDA was a budget-brand peanut butter distributed by King Nut, Inc. The supplier for this distributor was then identified as Peanut Corporation of America (PCA) of Blakely, Georgia. Products distributed by King Nut and other companies that used peanut products from PCA were placed on a national recall list, and PCA became the target of the CDC and other investigative and regulatory agencies. By 2009 PCA filed for bankruptcy, and is no longer in business. In 2013 the former owner of PCA was indicted on multiple charges, and was found guilty of conspiracy and other charges in 2014. The following paper provides an overview of the timeline of the outbreak, the response from the CDC, and the ensuing court cases and other legal actions related to the outbreak.

Background

The Peanut Corporation of America was originally founded in 1977 in the state of Virginia, and eventually grew into a large national company. The PCA maintained processing plants and distribution facilities in several states, including Georgia, a state well known at the time as the home of President Jimmy Carter, who had been a peanut farmer before entering politics. The PCA processing facility in Blakely, Georgia was primarily devoted to creating peanut butter, peanut paste, and other peanut-based products for use candies, cookies, and other products. Some of the peanut butter produced at the Georgia PCA plant was also sent to distributors who sold it at wholesale various budget-label and store-label brands. Many of the peanut-based products manufactured at the Georgia PCA plant were used for institutional purposes, such as in schools and prisons. Although the company focused on low-priced and budget-label products, it was one of the nation’s largest peanut processing companies, producing tens of millions of dollars in revenues annually in the 1980s and 1990s (Newman, 2014). This meant that PCA products were available to a broad cross-section of people across virtually every state in the country.

The Salmonella outbreak of 2008-2009 that was eventually traced to PCA was not the first time the company –or the Blakely plant in particular- had run into problems with the FDA and with state and local officials. The PCA was the target of a 1990 lawsuit by the American Candy Company, which had used peanut paste and peanut butter produced at the Blakely plant in several of its products. American Candy Company produced candies and other products for sale at stores such as Walmart, and a routine inspection of a larger order for the national retailer revealed that thousands of cases of peanut-based candies were contaminated with mold-related toxins. American Candy Company traced the source of the mold back to peanut products purchased from PCA, prompting the lawsuit. The following year another candy manufacturer, Zachary Confections, found the same mold-based toxins in several of its own products and in the peanut butter used to make them, which had come from PCA (Newman, 2014). Even before the outbreak of 2008-2009, PCA faced serious problems.

Along with the lawsuits from private organizations doing business with PCA, the company had been the target of regulatory agencies and inspectors on multiple occasions. The PCA plant in Georgia had been cited on numerous occasions for health and sanitation violations, and a sister plant in the state of Texas was also known to have similar issues. Despite the warnings and fines levied on the company in the 1990s and the 2000s, little was done to resolve the situation and the company continued to operate. When the 2008-2009 outbreak was traced back to the Blakely plant, subsequent investigations by federal, state, and local officials revealed a significant number and type of violations related to sanitation and safety issues. An FDA report on the Blakely plant found, among other things, that the facility was in disrepair, with holes in walls and ceilings where rats and other vermin could easily enter (fda.gov, 2009). Investigators also found mold growing on walls and on processing equipment, living and dead insects in the plant and in processing equipment, and other evidence that even the most routine sanitation methods and processes were ignored at the plant (fda.gov, 2009). It was clear for some time that the Georgia plant was an unhealthy and unsafe environment for processing food products.

Along with the sanitation issues uncovered at the Blakely facility, investigators found evidence in the company’s records that it had willfully ignored tests showing its products to be contaminated, and that it had often shipped products even after they had originally tested positive for contamination from Salmonella and other pathogens. According to FDA reports, the plant supervisors would often submit new samples for testing after receiving initial positive results, and if the subsequent tests came back negative they would sip the products. The FDA, CDC, and other oversight and regulatory agencies make it clear that salmonella and other contaminants can be dispersed throughout products like peanut butter, so a positive test from one sample should be used as a basis for disposing of the entire batch or shipment. Reports from the FDA and other agencies indicate that PCA was regularly using multiple tests as a means of getting around the need for disposing of products, and was willfully and purposefully shipping products that the company knew to be contaminated with Salmonella and other toxins.

Once the 2008 Salmonella outbreak was traced back to the Blakely plant, the FDA began a company-wide investigation into PCA’s other processing and distribution plants. Similar problems were found at PCA plants in Texas and Virginia, and the Texas plant was revealed to have never been properly licensed as food processing or handling facility. Like the Blakely plant, the Texas facility was found to have multiple and significant sanitation and health violations. Investigators found evidence of mold, insect and rat droppings, and processing equipment contaminated with bacteria and other toxins. A company-wide recall of products manufactured and shipped by all PCA plants in 2008 was ordered by the FDA, and the state of Texas went even further, ordering that all products ever produced by the Texas facility since it was opened several years earlier be recalled and destroyed. By February 2009 all three facilities –the Virginia, Georgia, and Texas plants- were shut down, and not long after the PCA filed for bankruptcy. It officially went out of business later the same year. Between the outbreak and the subsequent investigation there was nothing the company could do to survive.

The 2008-2009 Outbreak: Overview and Timeline

The first reports of the outbreak of Salmonella began coming in to state and federal agencies in late 2008. These initial reports did not necessarily indicate that a major outbreak was looming, and there was little evidence available at first to tie the Salmonella infections to any specific product. In early November 2008 the CDC began to identify small clusters of Salmonella outbreaks, but they did not immediately recognize them as part of a larger outbreak. By the end of the month, however, the CDC had identified 35 cases of Salmonella infections across 13 states, which indicated that a possible large-scale outbreak was looming (cdc.gov, 2009). With this information in mind, the CD began monitoring national reports of Salmonella infection to determine if a larger outbreak was imminent. The initial reports may not have been conclusive, but they were enough to spur the CDC to begin monitoring the situation.

The first step for the CD was to identify the particular strain (or strains) of Salmonella found in these infection clusters. There are numerous strains of Salmonella, and they can be found on a variety of food items. Salmonella contamination is typically associated with poor or inadequate sanitation procedures, and minor outbreaks can be linked to everything from local produce to manufactured products like PCA’s peanut butter. Further complicating the matter was the fact that the first signs indicating a more serious outbreak were reported in Minnesota, far from the Blakely, Georgia PCA plant that was eventually identified as the source of the contamination. Investigators in Minnesota originally sought a local cause, though the rapid uptick in reported infections across the country would soon make it clear that the outbreak was happening on a national scale. By identifying the specific strain, it was possible for the CDC and other organizations to expand the scope of their searches.

By early January 2009 there were over 400 reported infections of Salmonella in 42 states, all linked to the same strain of Salmonella Typhimurium. It was quickly becoming clear that this was a large-scale outbreak and was likely tied to a single source or a few linked sources. The Minnesota Department of Health was already out in front of the investigation, as it was the first state agency to determine that the reported infections in that state were part of a larger outbreak. The CDC, FDA, and the Minnesota Department of Health quickly began to coordinate their efforts to investigate the outbreak and to identify both the type and the source of the contamination. The swift rate at which people became ill was clearly alarming, but those numbers also made it possible for the CDC to focus their efforts.

One break in the investigation came when the Minnesota Department of Health was able to link outbreak clusters in that state to several institutions (cdc.gov, 2009). At roughly the same time, CDC studies were indicating that the specific strain of Salmonella associated with this outbreak was linked to peanut butter. This helped narrow the field of possible sources down for investigators, who were then able to look for links between peanut butter products and the institutions in Minnesota where clusters of Salmonella infections were being reported.  As a result of this investigation, the CDC and FDA were able to initially identify King Nut, Inc. as the source of the peanut butter products in the Minnesota institutions (fad.gov, 2009). Once identified, subsequent testing of the products from King Nut indicated that there were multiple instances of Salmonella contamination in the company’s peanut butter.

Once the FDA, CDC and Minnesota Department of Health had traced the Salmonella contamination to peanut butter from King Nut, Inc, it was only a matter of hours before the PCA was identified as the supplier of King Nut’s peanut butter. On January 9, 2009 the FDA launched a formal investigation into the Blakely, Georgia PCA facility; the following day King Nut issued a recall of its peanut butter. Six days later, while still under investigation by the FDA, PCA issued its first recall of its peanut butter and peanut paste. While most of the products containing PCA peanut butter were budget-label or institutional brands, the national Kellogg brand issued a recall of several product lines, including Keebler peanut butter crackers (fda.gov, 2009). Subsequent product recalls from other manufacturers followed in the coming days, and more products sourced from POCA were found to be contaminated. B February 2009 all products produced by PCA in Georgia and Texas since 2007 were recalled, and Texas later amended that recall all the way back to 2005. The initial identification of King Nut products as carriers of salmonella allowed researchers to trace the contamination to its source and to recall affected products.

Between November 2008 and February 2009, while the FDA and CDC were investigating the source of the outbreak and tracing it back to PCA, the number of infections was growing throughout those same months. The outbreak began with clusters of Salmonella infections in several states, as groups of a few dozen people reported getting sick. By January 2009 over 500 people had been infected with Salmonella as a result of this outbreak, with hundreds of those infected requiting hospitalizations (cdc.gov/mmwr, 2009). A CDC report from January indicates that at least seven, and possibly more, deaths had also been linked to the outbreak. A subsequent CDC report issued in May 2010 indicated that as many as 714 cases of Salmonella infection across 46 states were tied to the PCA-sourced outbreak (cdc.gov/mmwr, 2010).  In the brief window between late 2008 and early 2009 the contamination rate grew exponentially.

CDC and Pulsenet: How the Agency Identified and Tracked the Outbreak

Although the Salmonella outbreak of 2008-209 was investigated by the CDC and the FDA, not every case of foodborne illness receives the same level of attention and scrutiny. Most cases of foodborne illnesses are handled by local and state health care and regulatory agencies. Even in cases of outbreaks affecting clusters of people in a specific area or region, the responsibility of responding to and containing the outbreak is typically handled at the local or regional levels. Local hospitals and doctors treat patients who suffer from foodborne illnesses and local and state health departments and other agencies assume the task of identifying the source or sources of infection and taking necessary actions to stop the spread of the outbreak. Examples of such cases can include contamination found in restaurants and grocery stores; if a problem is found, it is up to the responsible agencies to issue citations, to close down facilities, or to take other appropriate actions. For every high profile case that receives a lot of attention, there are likely many others that go unnoticed or untraced.

When an outbreak of a foodborne illness spreads beyond a limited area, or appears to be linked to outbreaks in other areas, that is when the CDC begins to get involved. This is exactly what happened in the case of the 2008-2009 outbreak; as local and regional repots of infection by the same strain of Salmonella began to crop up in multiple states, the CDC quickly began to investigate these cases for possible links. While the CDC is responsible for monitoring and tracking more than just foodborne illnesses, the system it has in place for tracking a variety of diseases has become increasingly useful for monitoring the nation’s food supply. As the CDC notes, the U.S, food supply and distribution infrastructure is becoming more centralized, as large -scale producers and manufacturers are serving outlets and brands across the country. While this move towards centralization poses a greater risk for infections and contamination to spread quickly and across a larger area, it also means that the CDC can, at least in some instances, more quickly trace the source of contamination, as happened in the case of PCA. While the scale of PCA’s operation made it possible for the company to ship contaminated products to dozens of states and to multiple distributors, it also allowed the CDC to swiftly identify PCA as the source of the problem.

In order to effectively monitor for potential outbreaks of foodborne illnesses, the CDC maintains a number of different detection systems and communication networks. Hospitals and clinics across the country typically report instances of salmonella infections and other foodborne illnesses, and the CDC maintains a database of these reports. The CDC also coordinates its efforts with state and local health departments and federal agencies such as the FDA. This makes it possible for the FDA to report issues to the CDC and for the CDC to do the same with the FDA. In recent decades the advent of the Internet and other public and private computer networks has made it possible for this reciprocal system of communication and cross-reporting to become more effective, efficient, and responsive.

At the heart of the CDC’s detection system for foodborne illnesses and other potential pathogens is the Pulsenet system. Pulsnet is the name for a complex system of detection and identification technologies that allows the CDC to precisely indentify specific pathogens. Pulsenet utilizes a pulsed-field electrophoresis testing protocol; in simpler terms, Pulsenet produced a “DNA fingerprint” of each identified pathogen (cdc.gov, 2014). In the case of the PCA outbreak of 2008, Pulsnet was able to identify the DNA fingerprint of the Salmonella Typhimurium bacterium infecting people across the country. This means that the CDC could not only identify that it was the same basic strain of Salmonella Typhimurium; it could also determine that the Salmonella Typhimurium found in each cluster of outbreaks shared the same DNA fingerprint. By using Pulsenet, the CDC was able to quickly determine that each of the outbreak clusters was caused by a single source of Salmonella Typhimurium, which made it significantly easier for the agency to track the infection back to the source. Without the DNA fingerprint, it would have been more difficult to prove that each outbreak cluster was caused by the same original source of contamination, which would have had ramifications not just for tracking the source of the i8nfections, but for subsequent legal cases as well. By using Pulsenet, the CDC is able to coordinate and cross-check information in real time as food borne illnesses occur.

In addition to the communication networks and Pulsenet system, the CDC maintains an “OutbreakNet Team” which uses the information uncovered by Pulsenet to drive an investigation in the field. The OutbreakNet Team is responsible for federal-level oversight of large-scale, multi-state outbreaks of foodborne illnesses (cdc.gov, 2014). The OutbreakNet Team can conduct laboratory fieldwork and provide other investigative and research facilities during an outbreak, and it is responsible for directing the efforts of other federal, state, and local agencies during an outbreak. The effectiveness of the Pulsenet system and the OutbreakNet Team were clearly in evidence during the PCA outbreak of 2008-2009. Although the contaminated products shipped by PCA infected hundreds of people across dozens of states, the efforts of the CDC and the agencies working together with the CDC were able to swiftly identify the type of infection and trace it back to the source very quickly. Within days of the identification of a confirmed multi-state outbreak of a specific strain of Salmonella Typhimurium, the CDC and associated agencies had traced it to PCA and the process of recalling the tainted products was underway. The effectiveness of the Outbreak Team made it possible for the CDC to respond swiftly to the outbreak.

The Fallout of the PCA Outbreak

As noted earlier, the PCA had faced legal and regulatory issues in the past, but none as significant as the problems it faced once the company was identified as the source of a national outbreak of Salmonella.  While the company declared bankruptcy a few months after the initial outbreak, that was only the beginning of the company’s legal troubles. Despite the bankruptcy proceedings, a flurry of civil lawsuits followed from companies whose business had been affected because they purchased and distributed tainted peanut products sourced from PCA. Along with the cases brought by businesses, several individuals have sued PCA as well. One such case involves the family of Shirley Almer, who was one of the people who was killed by the outbreak of Salmonella. Almer’s son Jeff Almer is leading his family’s wrongful-death suit against PCA. Jeff Almer has been an outspoken public critic of PCA since the death of his mother, and has testified before Congress about the impact her death had had on him and his family (Newman, 2014).  In addition to these and other civil cases, the federal government issued a series of indictments against top company officials. The effort to hold officials from the company criminally liable for the illnesses and deaths related to the outbreak was virtually unprecedented, and it would eventually result in convictions for a number of former employees and the owner of PCA.

The criminal case against PCA began at the state level in Georgia, where state law enforcement agencies considered leveling charges against the company owner and other employees. This case stalled when the state determined that it could only charge the company with misdemeanors; subsequently, the Federal Bureau of Investigation took up the case against PCA (Newman, 2014). The FBI collected thousands of pages of documents from the Blakely plant and for other company sites, and combed through them for evidence of possible criminal wrongdoing. The investigation of PCA and company officials dragged out for several years, and critics such as Almer and others expressed concerns that nothing would ever come of the investigation. That changed in early 2013 when the U.S. Justice Department issued indictments against the former owner of PCA, Stewart Parnell, and several other company officials.

The trial involving Parnell relied on a variety of evidence, including testimony from former PCA employees, impact statements from Jeff Almer and others affected by the outbreak, reports from the CDC and the FDA, and on extensive company records. The case against Parnell was the first of its kind, as no company owner has ever been held criminally liable for causing an outbreak of salmonella or other foodborne illnesses. At the heart of the case was a virtual mountain of evidence that indicated Parnell was aware of the company’s sanitation problems for years, and that he ordered employees to ship product he knew to be contaminated. The case for this argument was based largely on a series of reports from the FDA and state agencies in the years leading up to the outbreak, the findings of the FDA and the CDC after the outbreak, and the company’s own email and other records that demonstrated Parnell’s knowledge of the problems. This combination of evidence from different sources would prove damning to the defendants.

Before the trial process began, Parnell and other company officials were called to testify before Congress in the same series of hearings in which Jeff Almer testified. Parnell and the other company officials invoked their 5^th amendment rights, refusing to testify (Newman, 2014). During these hearings several members of Congress referred to the same documents that would later for the basis of the criminal prosecution against the company, including emails in which Parnell ordered tainted products to be shipped. At one point during the hearings, a Congressman offered Parnell some of POCA’s own peanut butter, and asked Parnell if he would like to sample it. Not surprisingly, Parnell declined the offer. The hearings did little to quell the problems that PCA faced.

As the trial got underway, Parnell and his brother Michael, who also worked for PCA, faced a total of 76 charges. These charges included conspiracy, mail fraud, wire fraud, and the introduction of adulterated food into interstate commerce with intent to defraud or mislead (justice.gov, 2014). According to the indictment, both Stewart and Michael Parnell were aware that the company had a long history of sanitation and health violations and were further aware that the products responsible for causing the 2008 outbreak had tested positive for Salmonella. Other company officials named in the indictment included Samuel Lightsey and Mary Wilkerson, both of whom worked as supervisors and managers sat the Blakely plant. Samuel Lightsey was identified as the Operations Manager of the Blakely Plant, while Mary Wilkerson was identified as a senior administrative assistant. The indictment claimed that Michael Parnell, along with Lightsey and Wilkerson, reported directly to Stewart Parnell. Further, the indictment claimed that all four individuals named were aware of the problems at the plant related to sanitation issues, and were in the loop regarding the decision by Stewart Parnell to ship products he knew to be tainted. The indictment also listed a number of unindicted coconspirators who were presumably going to be called to testify. While there were only three people from the company charged in the indictment, those charges were serious, and carried potentially serious punishments.

Before the trail began, Lightsey agreed to a plea deal with prosecutors in exchange for his testimony against the Parnell brothers and Wilkerson.  Lightsey became a key witness for the prosecution, and he explained how the company used a number of methods to get around the rules and regulations related to testing food samples. The company created false Certificates of Analysis (COAs) for some shipments, and also ran repeated tests on different samples from the same product batches in order to secure negative test results. Lightsey claimed that he spoke up to company officials about the false COAs and fraudulent testing procedures, but was rebuffed. Lightsey further identified Wilkerson as the individual responsible for coordinating the COAs, and testified that she would have been aware that they were falsified. His decision to accept a pleae deal made it possible for the prosecution to draw out first hand testimony from Lightsey about the activities and decisions being made at PCA.

Along with the testimony of Lightsey, the prosecution relied on internal company emails and memos related to the COAs and the testing procedures for salmonella. One email written by Stewart Parnell directly ordered employees to ship products despite the fact that they had received a positive result after being tested for Salmonella. Other emails and memos indicated that dates for testing did not align with shipment dates, indicating that the company was shipping products without waiting for test results. The prosecution argued that this was a repeated patter of behjavior, and that the company regularly used falsified tests and COAs instead of waiting for test results. Michael Parnell testified that the company had only received one negative test result, though evidence shown at trial demonstrated that this was not true.  The prosecution then offered the jury a look at a number of key pieces of evidence, including reports from the FDA and the CDC produced after the investigations into the outbreaks. This combination of testimony and documentation provided the foundation for a strong case from the prosecution.

The combined weight of this evidence clearly convinced the jury that Stewart Parnell, Michael Parnell, and Mary Wilkerson were guilty of numerous crimes. In September 2014 the jury returned guilty verdicts against all three defendants on multiple charges, including conspiracy and intent to defraud. Despite the deaths that were directly caused by the salmonella outbreak, however, no one from PCA was charged with the illnesses or deaths of any of the victims, and the jury was instructed not to consider those deaths during their deliberations. The jury took only one hour to find the defendants guilty. Each of the three face potential fines totaling in the millions of dollars along with significant jail terms, though the sentencing phase of the trial has yet to occur as of this writing.

Immediately after the convictions were announced, the three defendants were taken into custody, though they later posted bond and were released pending sentencing. It is unclear exactly when they will be sentenced or what sentences they will receive, but the message sent by the jury was clear: the people responsible for the decisions at PCA were responsible for causing the 2008 salmonella outbreak. The trial and subsequent verdict represent the culmination of an extraordinary effort by state and federal investigators and the federal criminal justice system.  It remains to be seen whether the case against the Parnells and Wilkerson will establish a new precedent of holding business criminally accountable for their actions, but the seriousness of this case convinced at least one jury that such actions were necessary.

Conclusion

While it is too soon to tell if the PCA case will lead to a new era of criminal prosecutions, it does demonstrate that the system of communication and interaction among the CDC, FDA, and local and state agencies can effectively identify and deal with outbreaks of foodborne illness. It is only in recent years that such an investigation has become possible, as technological advances in the laboratory the CDC to fingerprint pathogens, while communication and computer technology allows multiple agencies to coordinate their efforts. At the same time, it must be acknowledged that the safety net in place that should have prevented this outbreak did not function properly, as state and federal agencies failed to force PCA to live up to regulatory standards. The PCA case reveals the strengths and flaws of the nation’s food safety system, and serves as an example of what is working and what needs to be improved.

References

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