E. coli in Qatar

Escherichia coli O157:H7, non-O157 E. coli, and Campylobacter spp. are among the top-ranked pathogens that threaten the safety of food supply systems around the world.

qatar.camelThe associated risks and predisposing factors were investigated in a dynamic animal population using a repeat-cross-sectional study design.

Animal and environmental samples were collected from dairy and camel farms, chicken processing plants, and abattoirs and analyzed for the presence of these pathogens using a combination of bacterial enrichment and real-time PCR tests without culture confirmation. Data on putative risk factors were also collected and analyzed.

E. coli O157:H7 was detected by PCR at higher levels in sheep and camel feces than in cattle feces (odds ratios [OR], 6.8 and 21.1, respectively). Although the genes indicating E. coli O157:H7 were detected at a relatively higher rate (4.3%) in fecal samples from dairy cattle, they were less common in milk and udder swabs from the same animals (1 and 2%, respectively).

Among the food adulterants, E. coli O103 was more common in cattle fecal samples, whereas O26 was more common in sheep feces and O45 in camel feces compared with cattle (OR, 2.6 and 3.1, respectively). The occurrence of E. coli in the targeted populations differed by the type of sample and season of the year.

Campylobacter jejuni and Campylobacter coli were more common in sheep and camel feces than in cattle feces. Most of the survey and surveillance of E. coli focused on serogroup O157 as a potential foodborne hazard; however, based on the PCR results, non-O157 Shiga toxin–producing E. coli serotypes appeared to be more common, and efforts should be made to include them in food safety programs.

 Risk of Escherichia coli O157:H7, non-O157 shiga toxin–producing Escherichia coli, and Campylobacter spp. in food animals and their products in Qatar

Journal of Food Protection®, Number 10, October 2015, pp. 1776-1924, pp. 1812-1818(7)

Mohammed, Hussni O.; Stipetic, Korana; Salem, Ahmed; McDonough, Patrick; Chang, Yung Fu; Sultan, Ali


Camera system detects foodborne toxin

Chemist Reuven Rasooly and his colleagues at the Agricultural Research Service’s Western Regional Research Center (WRRC) in Albany, California, have developed a simple and inexpensive system for detecting biologically active Shiga toxin, a product of pathogenic Escherichia coli serotype O157:H7. It is estimated that E. coli O157:H7 causes 73,000 cases of food poisoning and more than 60 deaths in the United States each year.

e.coli.O157.usda.detectThe new system involves the use of a camera and a light-emitting source to biologically determine active toxin. Affordable, sensitive devices like this are needed to reduce the sources and incidence of foodborne illness, says Rasooly, who works in WRRC’s Foodborne Toxin Detection and Prevention Research Unit. Current immunological tests, such as the ELISA, cannot distinguish between the active and inactive form of Shiga toxin.

“For example, in food processing, a heat-treatment method inactivates the toxin, but the ELISA cannot tell whether the toxin is active or inactive in the processed food,” Rasooly says. “Determining the activity of the toxin is very important, because the active form poses a threat to humans. The inactive form is nontoxic.”

Technology used to detect Shiga toxin and other pathogens is expensive and not a concern for resource-rich countries, he says. But equipment is typically too costly for developing countries, where the risk of foodborne illness and outbreaks is greatest. The camera system makes it easy and affordable for diagnostic labs that cannot afford a fluorometer, which is typically used to detect toxins.

“We demonstrated that our system is effective in measuring Shiga toxin activity compared with equipment costing 100 times more,” Rasooly says. “Afluorometer costs about $35,000, whereas the camera in this experiment costs $300.”

In the study, scientists constructed a fluorescence detection system using a camera and light source to measure GFP (green fluorescent protein) in a cell-based assay. A portion of a Shiga toxin-containing food sample was incubated with cells designed to produce GFP. The toxin in the sample inhibited the synthesis of GFP—reducing GFP production in relation to the amount of toxin present. The greater the toxicity, the less fluorescent the cells were.

Filters used with the light source and camera blocked wavelengths (signals) that would interfere with precise measurements of fluorescence. “We obtained these signal levels by taking a picture with a camera and analyzing the image with a free, available computer software that determines average pixel intensity,” Rasooly says.

The camera method, which can easily be adapted for detecting other foodborne toxins,was compared to a commercial fluorometer for detecting active Shiga toxin, Rasooly adds. Both instruments had the same level of toxin detection.

3 sickened: E. coli in Conwy county over

An E. coli O157 outbreak in the Conwy area of the UK, which affected three children has been declared over, health officials said.

e.coli.vaccine.beefA total of 83 other people were screened for E. coli O157 as part of the investigation by Public Health Wales and Conwy council but were given the all clear.

A childcare provider shut voluntarily during the outbreak but has reopened and is not believed to be the source.

Three affected children are recovering at home.

Use a thermometer? 5 sick in Vermont E. coli outbreak

A South Royalton restaurant voluntarily closed for several days recently and switched food vendors after being contacted by state officials who are investigating an E. coli “cluster” that has sickened at least five people.

worthy.burgerMeanwhile, state officials have released few details about their investigation, including the potential source of the contamination or how widespread the risk may be.

Jason Merrill, executive chef at Worthy Burger, said the Vermont Department of Health approached the restaurant’s leadership team last week and asked them to consider changing some of their food vendors out of precaution.

“They haven’t told me which ones they wanted me to change, so I changed pretty much all of my vendors,” Merrill said, noting he uses six or seven area farms to supply ingredients for the menu at Worthy Burger, which specializes in locally sourced food.

At least five people have contracted E. coli in what state officials have referred to as a “cluster,” according to the Vermont Department of Health. The locations of the five laboratory-confirmed cases, as well as a sixth case listed as “probable,” haven’t been divulged by health officials nor is it clear how the six cases are connected.

The health department is working on identifying the source of the contamination, spokesman Ben Truman said on Thursday.

Food safety silliness: 30-second food safety stories

There once was a dentist name Price.

He thought raw milk was all very nice.

miley.cyrus.tongueHe helped invent the Paleo diet.

And even, I’m told, Miley Cyrus likes it.

So it must be true.


But I want my food, like my medicine, to be based in 2015.

Not 1939.

30-second food safety stories.

Don’t get me started on microorganisms.

The evolution of dangerous E. coli

Enterohemorrhagic Escherichia coli (EHEC) is the causative agent of bloody diarrhea and extraintestinal sequelae in humans, most importantly hemolytic-uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP).

dangerBesides the bacteriophage-encoded Shiga toxin gene (stx), EHEC harbors the locus of enterocyte effacement (LEE), which confers the ability to cause attaching and effacing lesions. Currently, the vast majority of EHEC infections are caused by strains belonging to five O serogroups (the “big five”), which, in addition to O157, the most important, comprise O26, O103, O111, and O145.

We hypothesize that these four non-O157 EHEC serotypes differ in their phylogenies. To test this hypothesis, we used multilocus sequence typing (MLST) to analyze a large collection of 250 isolates of these four O serogroups, which were isolated from diseased as well as healthy humans and cattle between 1952 and 2009. The majority of the EHEC isolates of O serogroups O26 and O111 clustered into one sequence type complex, STC29. Isolates of O103 clustered mainly in STC20, and most isolates of O145 were found within STC32. In addition to these EHEC strains, STC29 also included stx-negative E. coli strains, termed atypical enteropathogenic E. coli (aEPEC), yet another intestinal pathogenic E. coli group. The finding that aEPEC and EHEC isolates of non-O157 O serogroups share the same phylogeny suggests an ongoing microevolutionary scenario in which the phage-encoded Shiga toxin gene stx is transferred between aEPEC and EHEC.

As a consequence, aEPEC strains of STC29 can be regarded as post- or pre-EHEC isolates. Therefore, STC29 incorporates phylogenetic information useful for unraveling the evolution of EHEC.

Highly virulent non-O157 enterohemorrhagic Escherichia coli (ehec) serotypes reflect similar phylogenetic lineages, providing new insights into the evolution of EHEC

Applied and Environmental Microbiology, October 2015, Volume 81, Number 20

Inga Eichhorn, Katrin Heidemanns, Torsten Semmler, Bianca Kinnemann, Alexander Mellmann, Dag Harmsen, Muna F. Anjum, Herbert Schmidtf Angelika Fruth, Peter Valentin-Weigand, Jürgen Heesemann, Sebastian Suerbaum, Helge Karchc, and Lothar H. Wieler


Diagnosis and management of foodborne illness

According to American Family Physician, the U.S. Centers for Disease Control and Prevention estimates that each year, one in six Americans will experience a foodborne illness.

vomit.2The most common causes in the United States are viruses, such as norovirus; bacteria, such as Salmonella, Escherichia coli, Campylobacter, and Listeria; and parasites, such as Toxoplasma gondii and Giardia. Resources are available to educate consumers on food recalls and proper handling, storage, and cooking of foods. Diagnosis and management of a foodborne illness are based on the history and physical examination. Common symptoms of foodborne illnesses include vomiting, diarrhea (with or without blood), fever, abdominal cramping, headache, dehydration, myalgia, and arthralgias. Definitive diagnosis can be made only through stool culture or more advanced laboratory testing. However, these results should not delay empiric treatment if a foodborne illness is suspected. Empiric treatment should focus on symptom management, rehydration if the patient is clinically dehydrated, and antibiotic therapy. Foodborne illnesses should be reported to local and state health agencies; reporting requirements vary among states.

Foodborne illness can be caused by a multitude of microorganisms such as viruses, bacteria, and parasites. Foodborne illness is a worldwide problem, and U.S. outbreaks often garner media attention and result in food recalls. Foodborne illnesses are becoming a greater challenge because of new and emerging microorganisms and toxins, the growth of antibiotic resistance, increasing food contamination caused by new environments and methods of food production, and an increase in multistate outbreaks.1 There are more than 250 identified pathogens that cause foodborne illness. The Centers for Disease Control and Prevention (CDC) estimates that one in six Americans (approximately 48 million) will become sick from a foodborne pathogen each year, resulting in 128,000 hospitalizations and 3,000 deaths.2 Most foodborne illnesses, hospitalizations, and deaths are caused by one of eight common pathogens: norovirus, nontyphoidal Salmonella, Clostridium perfringens, Campylobacter, Staphylococcus aureus, Toxoplasma gondii, Listeria monocytogenes, and Shiga toxin–producing Escherichia coli 2 (Table 13). E. coli is commonly divided into two broad types, Shiga toxin–producing—of which E. coli O157:H7 is the best studied—and non-Shiga toxin–producing, which includes enteropathogenic, enteroinvasive, enteroaggregative, and diffusely adherent E. coli. New pathogens emerge constantly, whereas others decrease in significance or disappear altogether. Predicting the emergence or disappearance of specific pathogens—other than in the setting of an identified outbreak—is difficult and has not significantly prevented or limited foodborne illnesses.


E. coli strikes in Missouri

Every time I go to Buffalo I want to barf.

Buffalo, Missouri, that is, and it’s next door to where Amy’s father lives and the roads are, um, adventurous.

5yrold-jpgThe Dallas County Health Department is investigating an E. coli outbreak, and the family of the affected children say they want to spread the word about the bacteria’s harmful effects.

“It was heartbreaking, I didn’t think my son to come through it,” says Sierra Sanford.

Sanford says her one-year-old son got sick from E. coli in early September. She says the bacteria led to hemolytic uremic syndrome, or HUS, which is a condition that caused his kidneys to fail. She says he was taken to a hospital in Springfield and then airlifted to a hospital in Saint Louis.

Angela Sanford, the child’s grandmother, says, “When we first saw him, it was horrible, my daughter had to literally set him up, lay him down, he couldn’t move.”

Angela Sanford says her five-year-old granddaughter got sick roughly a week after her grandson was sent to the hospital. She says E. coli made her sick, she contracted HUS, and her kidneys failed as well. The young girl is still in a Saint Louis hospital and Sanford says she has a long road to recovery, but she’s stable. Angela Sanford says her mother, the children’s great grandmother, also got sick from E. coli.

“I think the word needs to be out, people need to take precaution,” she says.

We went to the Dallas County Health Department and spoke with Administrator Cheryl Eversole.

She says, “We believe that this is a closed case, meaning this is a contained incident. We do not believe that this is anything that is going to affect a majority of the public. We feel that this may be just a localized incident within a family unit.”

UK toddler’s life turned upside down after HUS diagnosis

Just weeks ago Bobby Crosier was a happy, healthy two-year-old who was enjoying a bank holiday break with his mum and dad at a caravan in County Durham.

bobby.crosier.e.coli.sep.15Now, the Washington tot is in Newcastle’s Great North Children’s Hospital fighting off the illness which his worried parents are desperate to raise awareness of.

Mum Alex Crosier, 23, said: “When they told me, I was in a state of shock.

“I felt like someone has just grabbed our world and turned it upside down.”

The Crosier family, including dad Glen, 27, and three-year-old son Karl, had all been enjoying a weekend at a caravan in Witton-le-Wear during the August bank holiday weekend when Bobby started complaining of feeling unwell.

Alex said: “His eyes seemed a bit swollen and he wasn’t himself but we just thought it might have been a touch of hayfever.

“It turns out the problem was caused by E. coli, and the doctors told me it would just be a one-off case.

“When I heard that, I was so grateful. We had originally feared the situation might be a lot worse.”

Bobby has now started to recover on his own without the need for dialysis.

E. coli O157 more virulent when accompanied by beneficial bacteria

Scientists wonder why some people get so sick and even die after being infected by the foodborne pathogen E.coli O157:H7, while others experience much milder symptoms and recover relatively quickly. Now Penn State’s College of Agricultural Sciences researchers believe they have discovered an explanation.

e.coliO157H7Over the course of a four-year study, researchers co-cultured the pathogenic E. coli O157:H7 serotype with a nonpathogenic strain of the bacteria and inoculated mice. These mice got much sicker than mice that were infected with the pathogenic strain alone. The finding appears to be especially relevant because people normally have multiple strains of E. coli living in their intestines.

Most E. coli bacteria are harmless and are an important part of a healthy intestinal tract, noted co-author Edward Dudley, associate professor of food science. However, some E. coli are pathogenic, meaning they can cause illness by producing toxins that can result in bloody diarrhea, severe abdominal cramps or other more serious conditions, such as impaired kidney function.

“Within our intestines, each of us carries several hundred different types of bacteria, including E. coli, and E. coli comes in a large number of varieties. These range from organisms that just naturally colonize our intestines and provide us with benefits to organisms like the ones I focus on that have evolved to be very virulent,” he said. “This research suggests that some strains of harmless E. coli in our intestines can interact with pathogenic E. coli in ways that will either increase or decrease how much toxin the pathogen produces. And that may dictate how sick one gets with an E.coli infection, or even if an infection proves to be fatal.”

The study, which was published recently in Infection and Immunity, may be a significant step toward doctors being able to predict how an E. coli-infected patient will fare by evaluating a stool sample and analyzing the presence or absence of various strains of nonpathogenic E. coli. However, an advance like that would first require follow-on studies like those now being conducted in Dudley’s laboratory, aimed at determining which nonpathogenic strains of bacteria amplify the production of E.coli O157:H7 “Shiga” toxin.

“One of the issues with this particular pathogen is that by the time people are infected, we can’t do much for them,” said Dudley. “We can’t use antibiotics because antibiotics make E.coli O157:H7 more virulent — the only treatment is just to monitor the individual and make sure he or she doesn’t become dehydrated and be sure the kidneys stay functional.”

“What our findings suggest is that by looking carefully at the gut flora of someone who is sick — while we can’t necessarily treat them right away — we soon may be able to make a prediction about what the outcome of the disease is going to be. We can see if the patient is going to clear the organisms and have mild symptoms, or if they are likely to have something that is more serious.”

To test their hypothesis, lead researchers Kakolie Goswami and Chun Chen, recent Ph.D.s in food science, cultured multiple strains of E. coli, inoculated otherwise germ-free mice and followed the resulting infections. Researchers then examined the animals’ kidneys, intestines and livers after their demise, using molecular biology and DNA-sequencing techniques, along with biochemistry procedures. Goswami is now at Sample6,Cambridge, Massachusetts, and Chen is at Abbott Laboratories, Shanghai, China.

“These findings create a compelling argument to reconsider the appropriateness of assessing the virulence potential of E. coli O157:H7 strains solely by quantifying Shiga toxin production in pure cultures, because there are many strains of otherwise harmless E. coli present in the human intestine that have the potential to enhance Shiga toxin production,” Goswami said. “More research on the interactions between E. coli O157:H7 and the plethora of bacterial species present in the intestine is needed to appreciate how the gut microbiome affects virulence of this foodborne pathogen.”

The next step will be to study how pathogenic and nonpathogenic organisms communicate with each other and how modern medicine might use that information to minimize the course of disease, Dudley said. “We hope these findings have both a diagnostic potential and the promise of leading to information that will make the disease outcome less severe.”

The U.S Department of Agriculture supported this research.