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Blog Update: Multistate E. coli outbreak- Source Found: Chopped Romaine Lettuce


Infections Linked to Chopped Romaine Lettuce

This is an update of our previous blog 

The CDC and the FDA reported that their information indicated that chopped romaine lettuce grown in Yuma Arizona is probably the cause of the contamination with E. coli O157: H7. A common grower had not yet been identified.
As of April 12, 2018, 35 people from 11 states (Connecticut 2; Idaho 8; Illinois 1 Michigan 1; Missouri 1; New Jersey 7; New York 2; Ohio 2; Pennsylvania 9; Virginia 1; and Washington 1) were infected with the outbreak strain of E. coli O157:H7. Twenty-two ill people have been hospitalized, including three people who developed hemolytic uremic syndrome.
Epidemiologic data collected to date indicates that chopped romaine lettuce was the probable source of this outbreak. Twenty-six (93%) of 28 ill people that were interviewed reported consuming romaine lettuce in the week before their illness started. This percentage is significantly higher than results from common healthy people in which 46% reported eating romaine lettuce in the week before they were interviewed. Most of the interviewed people reported eating a salad at a restaurant, and romaine lettuce was the only common ingredient identified among the salads eaten. The restaurants reported using bagged, chopped romaine lettuce to make salads. At this time, ill people are not reporting eating whole heads or hearts of romaine.
Investigations are being conducted to find the source of the chopper romaine lettuce involved in the outbreak. A common grower or brand has not yet been identified. However, the data indicates that the chopped romaine lettuce was from the Yuma, Arizona growing region.  The Yuma region supplies romaine to the U.S. during November-March each year.
The current outbreak is not related to a recent multistate outbreak of E. coli O157:H7 infections linked to leafy greens reported in January this year. People in the previous outbreak were infected with a different DNA fingerprint of E. coli O157:H7 bacteria.

Multi state E. coli outbreak- Source unknown and Investigation Underway


The Outbreak

The CDC, the FDA, several states,  and U.S. Department of Agriculture’s Food Safety and Inspection Service are investigating a multistate outbreak of Shiga toxin-producing E. coli O157:H7 infections.
The investigation started by the New Jersey Department of Health, working together with the CDC and FDA. In New Jersey, ill people included in the outbreak had test results showing the presence of E. coli bacteria. Laboratory testing is ongoing to link their illnesses to the outbreak using DNA fingerprinting.
In this outbreak, there are currently 17 cases in 7 states: Connecticut (2), Idaho (4), Missouri (1), New Jersey (6), Ohio (1), Pennsylvania (2), and Washington (1). The 17 illnesses occurred until March 31, 2018. Six of those infected have been hospitalized, one of the hospitalized patients developed hemolytic uremic syndrome. Illnesses started on March 22, 2018, and data include cases that were diagnosed until March 31, 2018. The states associated with the outbreak are not clustered together, making a common source more difficult to find.
The investigation of the E. coli outbreak is still ongoing. To date, no specific food item, grocery store, or restaurant chain has been identified as the source of infections.  People that became ill are being interviewed by State and local public health officials, to determine what they eat and what they could have been exposed to in the weeks before getting ill.
PulseNet (the national sub-typing network) is being used to identify illnesses that might be part of this outbreak. E. coli bacteria isolated from ill people it tested using Pulse-Field-Gel (PFGE) and Whole Genome Sequencing (WGS). The DNA fingerprints obtained by PulseNet are used to identify possible outbreaks, and WGS gives a more detailed DNA fingerprint of the organisms. Some people may not be included in CDC’s case count because no bacterial isolates are available for the DNA fingerprinting needed to link them to the outbreak.

The Lawsuits are coming

Marler Clark from the Food Safety Law firm reports that his firm was retained by three patients affected in the multi-state E. coli outbreak. The clients reside in Idaho, New Jersey, and Pennsylvania. One client was hospitalized for three weeks after developing hemolytic uremic syndrome. Since the source of the outbreak is unknown, it is not clear who will be the target of the lawsuit.

Salmonella in Kratom causes FDA to Orders Mandatory Recall


Triangle Pharmanaturals mandatory Recall

The U.S. Food and Drug Administration (FDA) announced a mandatory recall for all food products containing powdered kratom manufactured, processed, packed, or held by Triangle Pharmanaturals LLC, (Las Vegas-based company) after several products were found to contain salmonella.
The products involved in the recall include Raw Form Organics Maeng Da Kratom Emerald Green, Raw Form Organics Maeng Da Kratom Ivory White, and Raw Form Organics Maeng Da Kratom Ruby Red.
Triangle Pharmanaturals manufacture, process, pack and/or hold additional brands of food products containing powdered kratom, including powder and encapsulated powder forms.   The forced recall follows Triangle Pharmanaturals, refusal to cooperate and voluntarily pull its products after they tested positive for Salmonella, the FDA said.
The agency statement said “This is the third time the FDA has started the process of using its mandatory recall authority, but the first time” it’s issued such an order due to a company rejected the voluntary recall request.
“Our first approach is to encourage voluntary compliance, but when we have a company like this one, which refuses to cooperate, is violating the law and is endangering consumers, we will pursue all avenues of enforcement under our authority,” FDA Commissioner Scott Gottlieb said.
“This action is based on the imminent health risk posed by the contamination of this product with salmonella, and the refusal of this company to voluntarily act to protect its customers and issue a recall, despite our repeated requests and actions,” said Dr. Gottlieb, M.D. “We continue to have serious concerns about the safety of any kratom-containing product and we are pursuing these concerns separately. But the action today is based on the risks posed by the contamination of this particular product with a potentially dangerous pathogen.”
The mandatory recall is the FDA’s first since it was given the authority to issue such an order for food products in 2011. Under the FDA Food Safety Modernization Act, the FDA has the authority to order the recall of food products when it determines that there is a reasonable probability that the article is adulterated and that its use could cause serious adverse health consequences or death to humans or animals.  Under the federal law, Dietary supplements are considered foods, not drugs. Two samples of kratom products manufactured by Triangle Pharmanaturals, and collected by the Oregon Public Health Division, tested positive for salmonella, as did four additional samples of various types of kratom product associated with the firm collected by the FDA.

What is Kratom?

Mitragyna speciosa, commonly known as kratom, is a plant that grows in Thailand, Malaysia, Indonesia and Papua New Guinea. The leaves of Kratom are used as an herbal drug by people of Southeast Asia.  Kratom leaves in low doses are used as a stimulant and at high doses as a sedative, recreational drug, pain killer, medicine for diarrhea, and treatment for opiate addiction.
The leaves can be chewed, dried and smoked, or powdered and consumed as a tea or in supplements. The product is promoted in the US as a way to treat muscle pain, diarrhea, and opiate withdrawal. Although it’s legal in the US, it’s illegal in some Southeast Asian countries.
The FDA would like people to avoid kratom or its psychoactive compounds, mitragynine, and 7-hydroxymitragynine, because there is substantial evidence that kratom affects the same opioid brain receptors as morphine and appears to have properties that expose people who consume it.

NutriZone recall Kratom

The FDA announced that NutriZone, LLC of Houston, Texas is recalling four different dietary supplements containing kratom due to contamination with Salmonella. The products were sold in Pennsylvania, Oklahoma, Washington, Missouri, Florida, Mississippi, California, and Texas.
The potential for contamination was noted after routine sampling and testing by the FDA revealed the presence of Salmonella. No illnesses have been reported to date in connection with this problem.

A multi-state outbreak of Salmonellosis linked to kratom

FDA Investigates Multistate Outbreak of Salmonella Infections Linked to Products Reported to Contain Kratom. On March 22, 2018, PDX Aromatics of Portland, Oregon, issued their second expanded recall in due to additional positive Salmonella samples associated with PDX Aromatics’ products. On March 23, 2018, Tamarack Inc.voluntarily recalled Eclipse kratom-containing powder products. These recalls are in addition to NutriZone, LLC of Houston and Triangle Pharmanaturals.
According to the Centers for Disease Control and Prevention (CDC), since late last month, 87 cases, in 35 states linked to kratom products have resulted in 27 hospitalizations. Epidemiological and laboratory data indicates the Kratom is the likely source of this outbreak. CDC reported a total of 87 people infected with outbreak strains of Salmonella I 4,[5],12:b:- (50), Salmonella Javiana (5), Salmonella Okatie (16), or Salmonella Thompson (16). Of 69 people with available information, 27 (39%) have been hospitalized. No deaths have been reported. Recent data showed additional strains including Salmonella Okatie, Salmonella Javiana, and SalmonellaThompson.
Of the 55 people interviewed, forty (73%) reported consuming kratom in pills, powder, or tea. Most people remembered consuming the powder form of kratom. The information collected about the purchasing location of kratom by the ill people, a single common brand or supplier of kratom has not been linked to the outbreak.
Most people infected recover without treatment, though the FDA said an unusually high number of people linked to the outbreak involving kratom were hospitalized.
Tests showed 26 different kratom products, from multiple manufacturers, were contaminated.

Detection of bacterial growth and Biofilm formation in pipelines made easy

By Giovanni Pavanello

The Biofilm Problems

On the surfaces that are in contact with water, a “biofilm” layer of microorganisms that are contained in a matrix (slime layer) can be formed. It is as a complex community of microorganisms, embedded in self-created extracellular polymeric substances (EPS). The biofilm is a microbial population adherent to each other and to the surfaces or interfaces enclosed in the matrix. Their presence in manufacturing pipelines can be responsible for a wide range of water quality and operational problems.
A Biofilm layer can form on any surface, even in extreme conditions (e.g., very high and very low pH values and temperature, in radioactive waters, even in space stations), and it causes a variety of problems:
  • Increase in the risk of pathogens – biofilm is the ideal environment for the proliferation of harmful bacteria by offering shelter and food;
  • Decrease in thermal efficiency of heat exchangers – for example, the biofilm is more insulating than calcium carbonate;
  • Microbiologically influenced corrosion (MIC) – also known as bacterial corrosion, it accounts for billions of dollars of industrial damages all over the world.
Large amounts of chemical substances (sanitizers, biocides, and disinfectants) are usually employed to prevent biofilm development in industrial piping systems. However, often they do not provide the expected results. In most cases, Clean-In-Place (CIP) and sanitation treatments are applied out on a regular basis (daily, or weekly) or when visible problems arise. The real need for neither the treatment nor its effectiveness is verified.
It is important to note that it is usually hard to take representative samples (“swabs”) from internal pipe surfaces. Standard plate counts applied to water samples are of limited use. Indeed, it is well known that bacterial growth on pipe surfaces is mostly unrelated to the presence/number of bacteria in the water. Planktonic (free-floating) bacteria attach to the pipes by the production of ESP; they multiply and form a mature biofilm, stabilizing the microcolony from environmental stress. Therefore, most bacteria live in biofilms, not free in the water.
Bacteria embedded in the biofilm are more difficult and expensive to eliminate, than free-floating planktonic bacteria. The extracellular substances (EPS) increase the bacterial resistance to external agents, by up to 1000x. As the biofilm matures, the ESP matrix becomes thicker. Thus it is much more resistant than an early-stage one. Sanitation and cleaning treatments should be applied on early-phase biofilm, to obtain the best results.
Moreover, when the biofilm is mature, its outermost layers tend to detach and float away. In these cases, it increases the likelihood of biofilm formation in other areas of the piping system.

The ALVIM Biofilm Monitoring System

Innovative technology for the detection of biofilms was developed by ALVIM, an Italian Company, in collaboration with the Italian National Research Council.
By measuring bacteria bio-electrochemical activity (a phenomenon known as “ennoblement” or “cathodic depolarization”), the ALVIM technology detects biofilm formation since its first phases, online and in real time. The technology allows checking the effectiveness of CIP and sanitation treatments, without the need for water sampling and lab analyses.   An example, from a reverse-osmosis (RO) system, is illustrated in the graph on the right. As it can be seen in the figure, the user can decide when to apply CIP, checking in real time if biofilm was actually removed.
The system helps in keeping track of bacterial settlement and growth inside water lines, tanks, and other surfaces in contact with the water and other liquids allowing checking, simultaneously, the efficacy of sanitation treatments.
The ALVIM probes are more specific than other sensors since they detect bacterial fouling (biofilm formation), not other kinds of deposit, such as minerals, proteins, fats, etc. This is extremely important since different fouling types require different treatments. It is important to emphasize that the ALVIM sensors are very sensitive to the detection of biofilm in its initial colonization phase, the best time to apply CIP and sanitation treatments.
ALVIM biofilm probes are currently used worldwide, in applications ranging from Cooling Towers to Food and Beverage, Paper Production, Oil and Gas and others, including large international Companies like Total, GDF Suez (ENGIE) and Danone.
The Massachusetts Institute of Technology (MIT) used ALVIM probes, in a Project regarding water distribution systems, and the European Defence Agency (EDA) indicated ALVIM Technology as a promising solution to the cleaning of biofilms. Overall, the ALVIM Technology allows for a simple and flexible approach to biofilm monitoring, considering different applications such as:
  • Analysis and characterization of biofilm growth;
  • Assessment and comparative evaluation of different chemical biocides, CIP and sanitation treatments;
  • Real-time, continuous monitoring of water treatment systems;
  • Automatic and/or remote control and optimization of sanitation treatment;
  • Effective prevention of pathogens, like Legionella, Listeria and Staphylococcus
More info available at: 

Precedence-setting Food Safety Case: Foster Chicken Farm found Liable in Salmonella Case

Meatingplace reported that a jury in Arizona returned a precedent-setting verdict in favor of 5 ½ years old boy (Noah Craten)   who had brain surgery in 2013, as a result of a massive brain abscess. The doctors determined that the abscess had been caused by bacterial meningitis due to Salmonella Heidelberg infection from what was believed to be chicken meat produced by Foster Poultry Farms.
Although the USDA does not consider Salmonella an adulterant in raw chicken, and even though cooking the chicken will kill the bacteria, the case establishes that chicken producers can be held liable for Salmonella contamination.
The jury on March 1 returned a verdict in the amount of $6.5 million in favor of Noah. The jury concluded that Foster Farm was negligent was based on microbiological and epidemiological evidence alone. Fluid removed from the abscess during surgery showed that the Salmonella bacteria present in the abscess matched one of the strains in the Foster Farm’s outbreak.
The jury seems to reject the argument that Salmonella contamination is natural to raw chicken. In a verdict that is a first of its kind, the jury found Foster Farm to be negligent in producing Salmonella Heidelberg contaminated product. It is a first to have the verdict based solely on epidemiological and microbiological evidence.
The jury attributed 30% of the fault to Foster Farms and 70% to family members for their preparation of the chicken. The net verdict against the family was $1.95 million.
Eric Hageman, the lead trial attorney for Noah Craten, claimed that the verdict established a precedent that could change the poultry industry. “Traditionally, Foster Farms and other poultry producers have argued that they are under absolutely no obligation to address even pervasive Salmonella contamination. The jury, in this case, said enough is enough. Clean up your act.” The jury’s verdict, Hageman said, “showed that Foster Farms could not simply hide behind USDA ‘approval’ of its chicken” and was “a rejection of the argument that poultry companies can produce contaminated product and then blame consumers who get sick from eating it.”
Noah Craten case was part of an extensive Salmonella Heidelberg outbreak investigated by the Centers for Disease Control (CDC) from March 1, 2013, to July 11, 2014. In this outbreak, 634 persons were infected with seven outbreak strains of Salmonella Heidelberg from 29 states and Puerto Rico, from March 1, 2013, to July 11, 2014. 38% of the sick persons were hospitalized, but no deaths were reported. The outbreak strains of Salmonella Heidelberg were resistant to several commonly prescribed antibiotics, as was the strain isolated from the abscess.
This case is groundbreaking and sets a precedent for food safety in the poultry industry.
According to Meatingplace  Foster Farms issued the following statement in response to the verdict: “Since 2013, Foster Farms has instituted a multi-hurdle Salmonella control program and committed to a company-wide Salmonella prevalence level of 5 percent in whole body chickens and parts. This compares to the USDA permissible level of 9.8 percent for whole body chickens and 15.4 percent for parts. Foster Farms’ current food safety performance record is recognized as being among the best in the US poultry industry, and the company is committed to advancing food safety for the benefit of consumers, customers, and the poultry industry.”

A Single Genetic Code Change Makes African Salmonella More Deadly

A new study has identified a single genetic code change that allows Salmonella Typhimurium (ST313) to play a significant role in human bloodstream infections in sub-Saharan Africa.  The study was published in Proceedings of the National Academy of Sciences, 2018 (PNAS) [Role of a single noncoding nucleotide in the evolution of an epidemic African clade of Salmonella Disa L. Hammarlöf, Carsten Kröger, Siân V. Owen, Rocío Canals, Lizeth Lacharme-Lora, Nicolas Wenner, Anna E. Schager, Timothy J. Wells, Ian R. Henderson, Paul Wigley, Karsten Hokamp, Nicholas A. Feasey, Melita A. Gordon and Jay C. D. Hinton; PNAS 2018] 
Invasive non-typhoidal Salmonellosis (iNTS) is killing approximately 390,000 people annually in sub-Saharan Africa. iNTS is caused by Salmonella that enters the bloodstream and spreads through the body. The African iNST is caused by a variant of Salmonella Typhimurium (ST313) that is antibiotic resistant, and affect people with deficient immune system. This Salmonella strain seems to be very similar to the Salmonella Typhimurium that causes gastrointestinal illness.
The team of scientists, led by Professor Jay Hinton at the University of Liverpool, used advanced genetic techniques to switch various single-nucleotide polymorphism (SNPs) to find the one responsible for the difference in the Salmonella strain between the antibiotic-resistant strain that can enter the bloodstream, and the one causing gastroenteritis.
The team analyzed hundreds of Salmonella genomes and showed that the Salmonella Typhimurium ST313 is closely related to the ST19 strains that cause gastroenteritis. The core genome of the two strains share over 4,000 genes, varies by only ~1,000 SNPs. They hypothesized that one or more of these SNPs are accountable for the difference between the ST313 and ST19.  A single nucleotide difference that was unique to the African ST313, was identified as the cause of the virulence of the strain and its ability to grow in the bloodstream.
Using transcriptomics (a type of RNA analysis), the scientists identified SNPs that affected the level of expression of important Salmonella genes. After studying 1000 different SNPs, they found the single nucleotide difference that is unique to the African ST313 strain which causes high expression of a virulence factor called PgtE that prevents Salmonella being killed in the bloodstream.  The virulence factor PgtE is an outer membrane protease Salmonella that causes diseases ranging from gastroenteritis to severe enteric fever.
There are thousands of SNP differences between different types of Salmonella; therefore it is surprising that a change of just one letter in the DNA sequence will cause such a profound difference in the disease-causing ability of the organism. Until now it has been hard to connect an individual SNP to the bacterial ability to cause a disease.
The researchers used animal models (chicken) to infect with bacteria with altered SNP to show that by removing it the organism lost its ability to cause the disease.


The research team from the Universities of Birmingham and Liverpool has identified a single-nucleotide polymorphism (SNPs), which helps the African Salmonella to survive in the human bloodstream.  SNPs represent a change in a single DNA letter between the two Salmonella strains. It seems to be the first link between an individual SNP and a disease.
The single SNP responsible for high levels of expression of the PgtE in the outer membrane protease was linked to the virulence of African S. Typhimurium ST313. The study has implications for bacterial genome-wide association studies, which they claim should clearly include a focus on noncoding regions of the genome. The study findings also emphasize the value of identifying all gene promoters in bacterial pathogens, to allow nucleotide differences to be correlated with the process of transcriptional initiation.