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Salmonellosis Outbreak
-Questions & Answers for Consumers and Industry

Salmonella Found in Basil Grown in Mexico, FDA Says (Update2)
By Catherine Larkin
Source of Article:
July 11 (Bloomberg) -- Salmonella, the bacteria that has sickened more than 1,000 Americans who ate tainted produce since April, has also been found in Thai basil grown in Mexico. The U.S. Food and Drug Administration identified salmonella during random testing of basil imported by Lucky Green Trading Inc., a family-run company based in Garden Grove, California, the agency said today in a statement on its Web site. The product has been recalled from Southern California, Arizona and Nevada, where it was distributed directly and sold at retail stores.
FDA officials have boosted inspections of Mexican exports as they look for the origin of the Salmonella Saintpaul outbreak that has spread to 42 states since mid-April. While the focus has been on certain types of tomatoes grown in Mexico and Florida, officials said this week that jalapenos caused some illnesses and that Serrano peppers and cilantro also are under investigation.
``Every importer from Mexico has to go through the inspection,'' said Tony Ton, whose family runs Lucky Green, in a phone interview today. ``That's a new thing. Every year, we used to have one or two occasions where FDA has to do a random inspection.''
No illnesses have been linked to Lucky Green's herbs. Their Thai basil comes from the town of Santa Rosa Tapachula in Nayarit, a state on the central-west coast of Mexico. The company doesn't sell any other products this time of the year, Ton said.
Three shipments of Thai basil from the same Mexican grower passed inspection last week, so Lucky Green is looking to see whether the latest batch may have been contaminated by another grower in the same area, Ton said.
Kimberly Rawlings, a spokeswoman for the FDA, didn't immediately return e-mail or voice-mail messages seeking comment.

Tomatoes, Jalapeno Peppers, Serrano Peppers and Cilantro Still Under Salmonella Saintpaul Suspicion
Posted on July 10, 2008 by Salmonella Attorney
Again, according to the CDC, since April, 1065 persons infected with Salmonella Saintpaul with the same genetic fingerprint have been identified in 42 states, the District of Columbia, and Canada. These were identified because clinical laboratories in all states send Salmonella strains from ill persons to their State public health laboratory for characterization. One new state, Mississippi, reports ill persons. The number of ill persons identified in each state is as follows: Alabama (2 persons), Arkansas (14), Arizona (49), California (9), Colorado (15), Connecticut (4), Florida (2), Georgia (25), Idaho (5), Illinois (104), Indiana (16), Iowa (2), Kansas (17), Kentucky (1), Louisiana (1), Maine (1), Maryland (29), Massachusetts (26), Michigan (8), Minnesota (18), Mississippi (2), Missouri (12), New Hampshire (4), Nevada (11), New Jersey (9), New Mexico (99), New York (30), North Carolina (14), Ohio (8), Oklahoma (24), Oregon (10), Pennsylvania (12), Rhode Island (3), South Carolina (2), Tennessee (8), Texas (408), Utah (2), Virginia (29), Vermont (2), Washington (11), West Virginia (1), Wisconsin (11), and the District of Columbia (1). Four ill persons are reported from Canada; three appear to have been infected while traveling in the United States, and one illness remains under investigation.

Among the 762 persons with information available, illnesses began between April 10 and June 26, 2008, including 315 who became ill on June 1 or later. Many steps must occur between a person becoming ill and the determination that the illness was caused by the outbreak strain of Salmonella; these steps take an average of 2-3 weeks. Therefore, an illness reported today may have begun 2-3 weeks ago. Patients range in age from <1 to 99 years; 46% are female. The rate of illness is highest among persons 20 to 29 years old; the rate of illness is lowest in children 10 to 19 years old and in persons 80 or more years old. At least 205 persons were hospitalized. One death in a man in Texas in his eighties has been associated with this outbreak. In addition, a man in his sixties who died in Texas from cancer had an infection with the outbreak strain of Salmonella Saintpaul at the time of his death; the infection may have contributed to his death.

Lukewarm Indictment of Jalapenos: Solving Outbreak Requires Thinking Outside the Box
Source of Article:
The bottom line is that the more the CDC and FDA speak, the more obvious it becomes that three months into this outbreak they do not have a rational explanation or even a reasonable theory to explain this Salmonella Saintpaul outbreak.
The latest announcement adds more smoke than light to the outbreak:
An initial epidemiologic investigation in New Mexico and Texas comparing foods eaten by persons who were ill in May to foods eaten by well persons identified consumption of raw tomatoes as strongly linked to illness. A similar but much larger, nationwide study comparing persons who were ill in June to well persons found that ill persons were more likely to have recently consumed raw tomatoes, fresh jalapeno peppers, and fresh cilantro. These items were commonly, though not always, consumed together, so that study could not determine which item(s) caused the illnesses.
Recently, many clusters of illnesses have been identified in several states among persons who ate at restaurants. Most clusters involve fewer than 5 ill persons. Three larger clusters have been intensively investigated. In one, illnesses were linked to consumption of an item containing fresh tomatoes and fresh jalapeno peppers. In the other two, illnesses were linked to an item containing fresh jalapeno peppers and no other of the suspect items. The accumulated data from all investigations indicate that jalapeno peppers caused some illnesses but that they do not explain all illnesses. Raw tomatoes, fresh Serrano peppers, and fresh cilantro also remain under investigation.
Basically the CDC is scrambling for highly unlikely explanations. On today¡¯s conference call, the CDC suggested a search for a farm that had been growing tomatoes and then, perhaps started growing jalapenos midway through the outbreak.

A few key points:
1) This suspicion of jalapenos and Serrano peppers is still just another epidemiological theory ? much as CDC had a theory about tomatoes a month ago. With thousands of samples taken, they still haven¡¯t found Salmonella Saintpaul on any jalapenos or anywhere jalapenos were served.
2) CDC hasn¡¯t given the date of the three restaurant clusters, so we don¡¯t know the relevance to public health today.
3) Although illnesses in two of the clusters were linked to items containing jalapeno and no other SUSPECT item, that does not mean they contained only jalapenos. If the outbreak was caused by a non-suspect item, such as tortillas, those items could still be at fault.
4) Note the advisory refers only to those with impaired immune systems ? that is always prudent. Note that this is much ¡°softer¡± than a recall or ¡°recommendation not to consume¡±? which probably indicates lower confidence in its finding by the CDC.
We think we need an approach that might not show up on the surveys. We want to suggest looking at two other possible vectors for this outbreak:
A) Chicken ? via cross-contamination
Chicken is commonly used in Mexican cuisine and is a common carrier of Salmonella. The CDC hasn¡¯t looked at chicken because the surveys don¡¯t show disproportionate consumption by sick people.
What if, though, the chicken is carrying the pathogen but, because it is properly cooked, the chicken itself doesn¡¯t get people ill?
Instead, the raw chicken is improperly handled; it contaminates the produce in the restaurant and that is how people get sick. This would never show up in the CDC surveys as a chicken issue ? but it would be.
We think we need to do some swabs at chicken-processing facilities looking for this relatively rare form of Salmonella.
B) Employees ? via inadequate hand washing
With over a thousand people sick and a multiplier of over 30 to account for sick people who aren¡¯t counted, we are talking about around 35,000 people estimated to be carrying or have carried this Salmonella Saintpaul strain. Many of these people must work in foodservice.
In the midst of the spinach crisis of 2006, we ran a piece about a Salmonella outbreak at a Wal-Mart store in Indiana. The story included this note from the Indiana Department of Health: ¡°We believe food handlers who didn¡¯t have any symptoms may have contaminated the deli and bakery products.¡±
How ever this started ? what if it is being spread by those 35,000 sick people, many, perhaps, asymptomatic? There has been zero mention of doing stool samples and health histories on the restaurant workers. We should do both.
When you listen to these calls, one doesn¡¯t get any sense of confidence that the government is on the way to solving this problem. CDC seems to be very caught up in certain standard operating procedures and, perhaps, when an outbreak is this different, it requires thinking outside of one¡¯s training and experience.
It is not obvious that the system set up by CDC and FDA is conducive to this type of creative thinking.


WASHINGTON, July 11, 2008 - Secretary of Agriculture Ed Schafer today announced that beginning next month, USDA will begin listing retail stores receiving meat and poultry products involved in Class I recalls - those of the most serious concern to public health. For some recalls, specific product information useful to consumers is not available to help identify recalled products that may still be in their home. Today's announcement provides a 30 day notice after the rule is published in the Federal Register before the process of listing retail stores takes effect.
"The identity of retail stores with recalled meat and poultry from their suppliers has always been a missing piece of information for the public during a recall," said Schafer. "People want to know if they need to be on the lookout for recalled meat and poultry from their local store and by providing lists of retail outlets during recalls, USDA's Food Safety Inspection Service will improve public health protection by better informing consumers."
USDA's Food Safety Inspection Service (FSIS) will post on its Web site a list of retail stores that receive products subject to Class I recalls, the highest risk category, generally within three to ten business days of issuing the recall release. A Class I recall is one that involves a reasonable probability of serious health consequences or death for those with weakened immune systems. Retail stores include supermarkets or other grocery stores, convenience stores, meat markets, wholesale clubs and supercenters. FSIS will not identify distribution centers, institutions or restaurants, since they prepare food for immediate consumption without packaging that is identifiable or available to consumers.
During the recall process, FSIS personnel verify that the recalling firm has been diligent and successful in notifying its customers of the need to retrieve and control recalled products and that the customers have responded accordingly. During the recall effectiveness checks, FSIS compiles a list of subsequent recipients as the recalled products are traced through each level of distribution to the retail level. The list of retail stores and locations compiled by FSIS personnel during this process will be posted on the FSIS Web site and shared with State and local public health officials where the retail stores are located.

Recall announcements from FSIS always include the name of the establishment recalling the meat or poultry, the reason for the recall, a description of the recalled product, any identifying product codes, the recall classification and contact information at FSIS and the company involved. The additional information releasing the names of retail stores receiving recalled meat and poultry will improve the consumers' ability to identify and discard or return the products they may have purchased and may still have in their home by checking the list of stores and locations. For further technical information on the final rule, contact Philip Derfler, Assistant Administrator, Office of Policy and Program Development, at (202) 720-2709 or by fax at (202) 720-2025
NOTE: Access news releases and other information at FSIS' Web site at

E. Coli Warnings and Recalls Seriously Delayed
Date Published: Monday, July 14th, 2008
Reports in central Ohio began emerging in mid-June that residents were falling ill from E. coli. Meanwhile, on June 9, the US Department of Agriculture (USDA) told Nebraska Beef executives that samples of Nebraska Beef were among those from a group of processing companies whose meat tested positive for E. coli. Dozens were sickened in Michigan and Ohio, many were hospitalized, and at least one person developed hemolytic uremic syndrome (HUS), a kidney disorder responsible for most deaths linked to E. coli O157:H7 infections.
The lag times prompted Ohio Agriculture Director Robert Boggs to announced he will no longer wait until other agencies or companies are ready to announce tainted products identified through lab tests run by his department. In this case, Ohio had test results confirming E. coli-contaminated meat on June 23; however, two days passed before that information was publicly released and Kroger Grocery issued a recall. Effective immediately, the Agriculture Department will notify other parties of test results, and if those parties haven¡¯t made the information public within three hours, or no later than 4 p.m., the department will issue a release. Exemptions might exist for food samples from federal agencies, Boggs added. ¡°I think the industry should have been more forthcoming more quickly in giving information to the public that product in their stores had been contaminated,¡± Boggs said.
Also, U.S. Secretary of Agriculture Ed Schafer recently announced a plan to advise consumers which retail stores sold products recalled by meat and poultry companies. A group of U.S. senators, including Ohio¡¯s Sherrod Brown, requested this change five months ago. ¡°There may be a gap in time between the need for a recall and the recall itself, but there should be no gap in public information,¡± Brown said in a release.
While Kroger chose to volunteer information that its products were tainted, no other retailers publicly linked themselves to Nebraska Beef, a Kroger supplier. And, although Kroger issued its recall on June 25 for meat with sell-by dates as late as June 8, it took Nebraska Beef five days to issue its first recall of 532,000 pounds of meat sent to companies in seven states. Over one week later, on July 3, Nebraska Beef issued a recall for 5.3 million pounds of its meat it said could be tainted and shouldn¡¯t be eaten.
With the announcement of the expanded recall, the U.S. Department of Agriculture reported that Nebraska Beef¡¯s production practices were insufficient to protect meat from contamination, products might have been produced in unsanitary conditions, and Nebraska Beef was lax in its response that its meat might be contaminated. Nebraska Beef has been involved in other issues where questionable practices and food contamination were found to have occurred. In 2003, the USDA went to court to try to shut down Nebraska Beef¡¯s Omaha packing plant after citing it for numerous violations. Three years later, Minnesota public health and USDA officials linked an E. coli 0157:H7 outbreak in ground beef that killed a Minnesota woman to Nebraska Beef. In 2007, Nebraska Beef sued the USDA saying its inspectors had unfairly targeted it.

Georgia E. Coli Illnesses Linked to Nebraska Beef E. coli Recall
Posted on July 9, 2008 by E. coli Lawyer
Source of Article:
The widening cluster of E. coli O157:H7 infections in Georgia may be linked to an outbreak E. coli illnesses in Ohio and Michigan. The Moultrie Observer reports that preliminary testing has linked the at least 9 Georgia cases to the 41 in Ohio and Michigan, which have been traced back to beef products from Nebraska Beef Ltd. of Omaha.
E. coli infections began showing up in central Ohio in mid-June, paralleled by a sharp increase in E. coli cases in Michigan. By June 20, officials had genetically linked many of the Ohio and Michigan cases; the days that followed, the outbreak was traced to ground beef from Kroger stores. With illnesses nearing 30, Kroger initiated a voluntary recall on June 25. On June 30, FSIS announced that the tainted meat had been traced back to Nebraska Beef Products, and a recall of 531,707 pounds of ground beef products was initiated. On July 2, the Kroger recall widened to 20 states. On July 3, the Nebraska Beef recall was widened to include 5.3 million pounds. Georgia is not on the Kroger recall list, but is part of the Nebraska Beef recall.
Nebraska Beef Ltd. is already enmeshed in lawsuits stemming from tainted meat. In 2006, seventeen people were infected with E. coli O157:H7 after eating Nebraska Beef products prepared at a church dinner; one woman died. Nebraska Beef responded by suing the church. A lawsuit has just been filed on behalf of an Ohio resident who became ill from eating Nebraska Beef products in the recent outbreak there.
We also filed an additional lawsuit against Nebraska Beef today. The recent filing occurred today in the United States District Court, Southern District of Ohio, Eastern Division, on behalf of Pickerington, Ohio resident Dawn Grieves, who was infected with the toxic E. coli strain O157:H7 after eating ground beef processed by Nebraska Beef Ltd.
The lawsuit states that Ms. Grieves consumed Nebraska Beef Ltd products in the early part of June, 2008 and fell ill on June 5. She began to have increasingly severe symptoms including abdominal cramps, vomiting, and diarrhea, which sent her to the emergency room on June 6. She was given medication and returned home. Her health continued to deteriorate, and when and samples taken during her ER visit revealed that she had been infected with E. coli O157:H7, she returned to the hospital. She was admitted on June 9 and remained there until June 13. She continues to recover from her illness.

Salmonella scare puts brakes on border produce trucks
By LYNN BREZOSKY San Antonio Express-News
Source of Article:
MCALLEN ? The Food and Drug Administration's attempt to target a source for the nationwide salmonella outbreak has effectively shut down Texas border tomato traffic ? and that of cilantro, jalapenos, and other peppers and produce, even though tainted ones have yet to be found in Mexico.
Industry losses, estimated at $250 million for the initially implicated tomatoes alone, are mounting as the FDA widens its probe. The standstill at the border is spreading through a distribution chain that reaches from the fields of Coahuila, Mexico, to wholesale markets in cities like Atlanta and Chicago.
It's evident in the rows of packing sheds in McAllen that normally bustle this time of year with northbound shipments of tomatoes and peppers.
Cold storage rooms stand empty. Conveyor belts are still. Owners pace their bare warehouses fielding cell phone calls from customs brokers for word on whether they can move what rapidly perishing product they still have.
Meanwhile, idle workers wonder how long they'll have jobs.
"I've got almost one month without doing nothing and losing our sales," said Abraham Dajlala of GR Produce. "If we cross one load of jalapenos right now, the FDA takes eight to 10 days to give you the (test) results. By that time it's too late. I've got jalapenos in Mexico right now, waiting in the fields."

Inspections widen
In Texas, the main routes for imported Mexican produce funnel through the Pharr-Reynosa International Bridge east of McAllen, where trucks are routinely inspected before heading to unload in border packing sheds.
As the rare strain of salmonella Saintpaul that began sickening people in April began appearing in more and more states, the detective work by the FDA and Centers for Disease Control and Prevention extended to fields and distribution spots across the nation.
As of Saturday, 1,065 people in 42 states, the District of Columbia and Canada had gotten ill. The deaths of an elderly Texas man and another Texan who died of cancer, but had contracted salmonella, were associated with the outbreak.
Last week, FDA inspectors were dispatched to Mexico, where they began inspecting fields, equipment and water sources.
And at the border, they have been taking samples from truckloads of tomatoes, hot peppers and cilantro. The FDA says it takes three to four days to clear a sample, and during that time the product can be moved to its final destination, but not sold for consumption.
But importers won't risk moving anything across the country only to find they'll have to recall it. And with weekends and holidays like July 4, they say the average wait has been more like eight to 10 days.
So, most are telling their Mexican producers to keep the product home.
Decay starts as soon as the chiles are cut from the plant, so there's some hope of delaying the harvest until the FDA declares the batch safe. But importers know that could also lead to a mad dash for the border, backups at the bridge and a saturated market.
Jim Prevor, editor of Produce Business magazine and the Web site Perishable Pundit, thinks the FDA probe is doing more harm than good at this point.
CDC statistics show 1.4 million cases of salmonella poisoning a year, and attempts to trace back to a contaminated product may not begin until a week or longer after it was consumed. The produce now being tested form the ingredients to salsa, but officials cannot say whether salsa, or any particular food, is the culprit.

No green light
With tomatoes, Mexican and U.S. states were listed once they were cleared by the FDA. That hasn't been the case with hot peppers or cilantro. What's most frustrating to the industry is that the search has been so wide and fruitless.
"Basically, the FDA is acting in such a way that thousands and thousands of farmers are victims, and they've done nothing wrong," Prevor said. "It's not really helping public health, either. It would be one thing if they were really saving countless lives, doing wonderful things, but the risks are so small, the cause of the problem so uncertain."
Representatives for the FDA and CDC refused to say how many inspectors are on the border, what kind of testing is being done, or what percentage of cases could have involved a restaurant meal.
On a conference call with reporters Thursday, FDA official Dr. David Acheson described how the detective work had taken them from suspecting tomatoes to broadening to hot peppers and cilantro.
"It's just been a spectacularly complicated and prolonged outbreak," he said. "We've pursued all the usual angles, used all the tools multiple times ... and we're not there."
The information about tomatoes and jalapenos came from two different studies that didn't implicate one or rule out another.
"We are quite sure that neither tomatoes nor jalapenos explains the entire outbreak," CDC's Dr. Robert Tauxe said. "We're presuming that both of them have caused illnesses."
John McClung of the Texas Produce Association, a former food safety inspector, said the industry recognized the challenge facing the FDA, but thought the methodology was flawed and outdated.
"As they become more and more desirous of pinning this tail on some donkey or another, they spread their net wider and wider, which means they are less likely to get results and more likely to get commodities damaged in the process," McClung said.

'Out of business'
Mexican officials said the FDA has unfairly crippled their tomato business and Friday declared that the country's crop was clean. Two states, Jalisco and Sinaloa, have not yet been cleared by the FDA, but they account for 40 percent of the exports. Mexican officials say they have tested and proven the product safe. Dajlala, the McAllen importer, said his growers in Mexico have pristine, state-of-the-art operations.
"It's unbelievable, better than here," he said. "The problem is not the grower."
In another packing shed a few rows down, Raul Trevino of ELC General Produce waited anxiously Friday afternoon for word that tests were OK and he could move about $20,000 worth of jalapenos. They had been sitting in his walk-in cooler since Monday, and some were beginning to turn orange, a sign of spoiling.
He said he has been working with the FDA but told representatives he couldn't hold out much longer. "I tell them, 'You know what, I'm going to be out of business soon,' " he said.

Pathogen Genes Targeted In Studies To Protect Salad Veggies
Source of Article:
ScienceDaily (July 14, 2008) ? No one knows exactly how microbes like Listeria monocytogenes or Salmonella enterica can attach themselves to the bumpy leaves of a cabbage or the ultra-fine root hairs of a tender young alfalfa sprout.
Listeria monocytogenes on this broccoli sprout shows up as green fluorescence. The bacteria are mainly associated with the root hairs. (Credit: Photo by Lisa Gorski)
It's a mystery that Agricultural Research Service (ARS) food safety scientists in Albany, Calif., are intent on solving. The work, based at the ARS Western Regional Research Center, may lead to new ways to protect cabbage, sprouts and other salad favorites from attack by foodborne pathogens.
Microbiologist Lisa A. Gorski, for instance, led an investigation several years ago that was the first to document the genes that L. monocytogenes uses during a successful invasion of cabbage leaves. Gorski did the work with Albany colleague Jeffrey D. Palumbo and others.
Though scientists elsewhere had looked at genes that this Listeria turns on--or "expresses"--when it's grown on a bed of gel-like agar in a laboratory, no one had, at the time of Gorski's investigation, ever documented genes that this microbe expresses when it grows on a vegetable.
Listeria is perhaps best known for establishing colonies in humans, not on green plants. But the team found that Listeria, when invading cabbage, calls into play some of the same genes that plant-dwelling microbes routinely use to colonize and spread harmlessly on plants.
In newer work, Gorski wants to pinpoint genes responsible for the widely varying ability of eight different Listeria strains to successfully colonize the hair-thin strands, called root hairs, of alfalfa sprouts.
She's also interested in studying, and disabling, genes that help some Listeria colonies resist being washed off by water.
Adapted from materials provided by USDA/Agricultural Research Service.

New study sheds light on how intracellular pathogens trigger the immune system
Source of Article:
Berkeley -- Disease-causing microbes like the food-borne bacterium Listeria monocytogenes specialize in invading and replicating inside their animal hosts' own cells, making them particularly tricky to defeat. Now, a new study led by biologists at the University of California, Berkeley, has identified a molecular alarm system in which the intracellular pathogen sends out signals that kick the immune response into gear.
The findings, to be reported the week of July 14 in the journal Proceedings of the National Academy of Sciences, shed light on how the cells recognize and destroy the pathogenic bugs living within their walls, and may even provide new targets for the research and development of new vaccines and drugs.
The pathogens' signals come from multidrug resistance transporters (MDRs), membrane proteins used by a wide variety of organisms to pump out a broad range of molecules from their systems. Similar transporters have been linked in other studies to the development of resistance to multiple drugs that are toxic to the pathogen. This study is the first to connect multidrug resistance transporters directly to stimulation of the immune system, although the nature of the molecules that the bacteria are spitting out remains unclear.
"For the MDRs to work, the pathogen needs to be alive, so this study actually shows how the immune system can tell the difference between a living, harmful microbe and one that is dead," said the study's principal investigator, Daniel Portnoy, a UC Berkeley professor with joint appointments in the Department of Molecular and Cell Biology and the School of Public Health, and associate director of the Berkeley Center for Emerging and Neglected Diseases. "This is important because you don't want the immune system to overreact to non-threats, which is what happens in autoimmune disorders such as inflammatory bowel disease, asthma and multiple sclerosis."
The Listeria bacterium makes headlines when it contaminates deli meats, raw cheeses, cole slaw and other foods. According to the Centers for Disease Control and Prevention, Listeria causes some 2,500 infections and 500 deaths each year, and at greatest risk are people who have weakened immune systems or are pregnant.
The bacteria first trick immune cells into swallowing them, where they become encased in bubbles called vacuoles. The bacteria become dangerous when they break out of these bubbles into the cells' internal fluid, or cytosol, to multiply and spread the infection. The role of MDRs is not clearly known, but the results of this study plainly show that one particular MDR transporter is necessary for the host to respond to the infection, the authors said. In addition, overexpression of this or other related MDRs leads to an enhanced host immune response.
"The only way the bug molecule enters into the cytosol is if the bacterium is virulent," said Portnoy, who is also a member of UC Berkeley's Health Sciences Initiative. "We know that there are different immune system receptors in different compartments of a cell, but until this paper, it was not understood exactly how the cytosolic surveillance system was triggered. Our findings suggest that the molecules pumped out by the pathogen while it's in the cellular fluid help the immune system gauge whether a bacterium is a threat based upon its location inside the cell."
The researchers isolated the role of multidrug resistance transporters by manipulating specific genes in the bacteria that controlled their expression and then measuring how increased or decreased activity by the transporter proteins impacted levels of interferon beta, a protein produced by the immune system that rally more disease-fighting cells when infections are detected.
They found that greater MDR expression led to greater stimulation of the immune system, as measured by interferon beta levels.
Strains of Listeria with higher levels of MDR expression increased interferon beta levels up to 20-fold compared with unmodified, wild-type Listeria in cell cultures, the study found. Tests in mice infected with those same mutant strains of Listeria had bacterial loads that were 20 times lower in their livers, although the researchers could not attribute the decreased levels solely to the higher levels of interferon beta.
"This paper raises the classic issue of the tug-of-war in the evolution of the host and the pathogen; it's a never-ending arms race," said Gregory Crimmins, UC Berkeley graduate student in molecular and cell biology who, along with former UC Berkeley post-doctoral researcher Anat Herskovits, was the study's co-lead author.
The study results could provide clues to the actions of other intracellular pathogens, such as the bacteria responsible for tuberculosis and Legionnaires' disease, since they also activate similar immune mechanisms, the researchers said.
Crimmins noted that better understanding of how the class of interferons in this study is triggered could have implications for a variety of diseases. "Type I interferons have wide-ranging effects on the immune system, and are used to treat multiple sclerosis, hepatitis C and some types of cancer," he said. "The strains generated in this study may provide novel insight into the role of Type I interferons in coordinating the host immune response."
"By understanding the pathways of innate immunity, we can better understand acquired immunity, and that is important for vaccine development," added Portnoy. "The concept of making safe but fully effective vaccines is still a challenge, especially for intracellular pathogens."
Portnoy pointed out that weakened Listeria is already being used to develop cancer vaccines by Anza Pharmaceuticals, a Concord-based biopharmaceutical company with which he consults.

E.coli inquiry wants latest details of systems changes
Jul 12 2008 by Madeleine Brindley, South Wales Echo
Source of Article:
THE long-running E.coli public inquiry is calling for more evidence as its switches track to preventing another deadly outbreak.
Professor Hugh Pennington, who chairs the inquiry, will now also produce recommendations to stop an outbreak similar to the one in the Valleys in 2005 from happening again. His decision comes as the inquiry team considers thousands of pages of evidence about the outbreak, which killed five-year-old Mason Jones and infected more than 150 other children and adults.
Mason¡¯s mum Sharon Mills today said the move showed how ¡°thorough¡± Prof Pennington was being.
And Stephen Webber, of Hugh James solicitors, who represents the families, said: ¡°This is a really positive step and it will be very interesting to see exactly what systems have been put in place since the outbreak.
¡°We know that Rhondda Cynon Taf has set up new procurement procedures, but of particular concern to us is whether Bridgend inspectors would think that a business operating with just one vacuum packer is still appropriate.¡±
Prof Pennington, who is expected to publish a full report and recommendations later this year, said: ¡°I have asked participants in the inquiry to provide me with a comprehensive and up-to-date picture of any changes that have been made to systems and procedures since the outbreak and any others that are planned.¡±
The closing date for submissions to the E.coli public inquiry is August 11.

Official: Public To Learn Sooner Of Tainted Goods
July 14, 2008
Source of Article:
COLUMBUS, Ohio -- Ohio officials will speed up public notification of tainted food products in the wake of an E. coli outbreak that sickened people in Ohio and Michigan, the state's agriculture director said.
The department will notify the public of laboratory test results within three hours, instead of waiting for other agencies or companies to make their own announcements, Agriculture Director Robert Boggs told The Columbus Dispatch.
Ohio officials confirmed on June 23 that beef tested in state labs was contaminated with E. coli, but the information was not released until June 25.
"I think the industry should have been more forthcoming more quickly in giving information to the public that product in their stores had been contaminated," Boggs said.
Food samples from federal agencies might be exempt from the policy, Boggs said.
The tainted meat was later traced to Nebraska Beef Ltd., prompting the company to recall 5.3 million pounds of beef.
Some of the recalled beef was sold by Cincinnati-based Kroger Co. stores. The grocer has recalled ground beef products in more than 20 states.
At least 41 illnesses in Michigan and Ohio have been tied to Nebraska Beef's products.
The federal government has criticized Nebraska Beef for responding slowly to indications that its products might be tainted with E. coli.
The company proposed a new plan last week to satisfy the USDA's concerns, but details of the changes were not released.
USDA inspectors will check on the plant, which is in Omaha, over the next 90 days to make sure Nebraska Beef completes the changes it proposed, USDA spokeswoman Amanda Eamich said.
Several lawsuits have been filed against privately held Nebraska Beef as a result of the E. coli outbreak and recall. The company slaughters about 2,000 head of cattle a day and employs about 800 people.
Federal food safety regulators should have more power and focus only on public protection, said Dr. William Schaffner, professor and chairman of the department of Preventive Medicine at Vanderbilt University.
"The (USDA) is predicated on the notion that what the USA produces on the farm and on the ranch is a good thing," Schaffner said.
The federal Centers for Disease Control and Prevention estimates that E. coli sickens about 73,000 people and kills 61 each year in the United States. Most of those who die have weak immune systems, such as the elderly or very young.

Effective chemical wash targets Salmonella, E. coli
Date: 14/07/2008 Source of Article:
Reducing bacterial contamination in food products poses many problems for the food industry. While it is quite obviously important to protect against food-borne pathogens such as Salmonella, e. coli, and Listeria, equally important is the effective preservation of taste. To date, this has been a puzzle difficult to resolve. Recently, University of Georgia (U.S.) scientists, led by Dr. Mike Doyle, developed a chemical wash for poultry and produce that might solve the conundrum that has baffled many.
Doyle is an internationally recognized authority on food safety whose research focuses on developing methods to detect and control food-borne bacterial pathogens at all levels of the food continuum, from the farm to the table. He has served as a scientific advisor to many groups, including the World Health Organization, the Food and Drug Administration, the U.S. Department of Agriculture, the U.S. Department of Defense and the U.S. Environmental Protection Agency.
Scientist Live spoke with Dr. Doyle about his research.
How did you first get involved in developing a chemical wash for Salmonella?
One of our primary missions at the Center for Food Safety is to develop practical approaches for reducing and controlling harmful bacteria in foods. That is our primary driving force - developing better methods that consumers, producers, or processors can use to reduce pathogen contamination and increase detection. We have a project through the state of Georgia to reduce Salmonella contamination on poultry. As part of that project, our goal is to evaluate different chemical treatments that can potentially inactivate Salmonella.
At the beginning, we always start out with a pure system then move into more complicated ones like water with poultry feces. What we learned from our research was that a particular combination of chemicals - specifically an organic acid that is not frequently used in foods and a detergent - had a dramatic effect on reducing Salmonella populations, not only in water but also on food products like vegetables and poultry meat.
What are the shortcomings of current washes widely used in the food industry?
Presently, chlorine is used in poultry and fresh-cut produce antimicrobial washes. Chlorine is not entirely effective as an antimicrobial in the presence of organic loads which includes protein materials like blood. In the presence of protein, chlorine also produces by-products of which some are carcinogenic. So there is an interest in coming up with alternatives. There are some alternatives but they are not fully effective and don't kill as many bacteria as our treatment does. Moreover, they may damage tissue of particularly sensitive foods like leafy greens - lettuce and spinach, for example - that are very sensitive to certain treatments.
Does the wash you developed fight other forms of bacteria?
We tested against E. coli O157:H7, Salmonella, and Listeria. It's effective against all three.
Would food producers be able to use the wash on a wide range of products?
That is yet to be determined. For produce, we have concentrated on lettuce and tomatoes. There is considerably more to be evaluated. From past experience, lettuce has been very difficult to treat and keep from browning over a short period of time. For example, when we use combinations of lactic acid and acetic acid at levels needed to kill bacteria, we find that leafy green tissue begins to brown within a few days. That is why we are excited about this treatment. The tissue does not brown in a few days after treatment. Rather it retains its green color for several weeks.
Is the wash effective against non-bacterial microbes?
That is what we plan to test. We want to evaluate its efficacy on parasites like Cryptosporidium and Cyclospora as well as some viruses.
Many chemical washes are known to produce slightly altered tastes. How does your wash perform?
The wash treatment performs well in this regard. I tasted treated products and don't detect any off flavor or odor or discoloration.
What is the next step for your lab in terms of this project?
One of our priorities for the wash is to reduce Salmonella contamination on poultry and we have some additional approaches we would like to apply, including pre-harvest. By that I mean as chickens are loaded onto the truck there may be an opportunity to apply the wash to feathers and reduce the Salmonella contamination on the feathers. The outer surface of chickens is often the source of Salmonella on the meat. Also, we are looking at the scald water tanks which are another source of contamination to determine if we can successfully apply the treatment in the scald water. Finally, we want to apply the treatment with electrostatic spraying - especially to feathers - to see if we can reduce contamination using less treatment solution.

USDA looks at ways to decontaminate leafy produce
By staff reporter ource of Article:
10-Jul-2008 - Combining sanitizers with ultrasound, optimizing oxygen conditions and not reusing washing water can reduce bacterial contamination of lettuce and leafy greens, according to a summary of recent USDA laboratory research.
The findings are published in the July issue of the US Department of Agriculture's (USDA) science monthly, Agricultural Research.
The research is likely to be of interest to growers, processors and retailers, as an outbreak of a foodborne disease can be extremely costly, as well as potentially fatal for the consumer. he USDA said that researchers at its Produce Quality and Safety Laboratory (PQSL) in Maryland have been focusing on ways to keep salads safe at processing plants before and after bagging.
Microbiological safety is a key issue for ready-to-eat prepared vegetable tissues, because they are intended for consumption raw, without further preparation or cooking.
Bacteria can contaminate crop plants in situ during the growth of the plant or during harvesting, handling, processing, distribution or preparation.

PQSL technologist, Yaguang Luo, in an examination of wash waters and sanitizers, simulated washing methods to analyse how processing practices could affect safety and quality of precut lettuce, stated the ARS article. For the study, according to Agriculture Research, romaine lettuce leaves were sliced and then rinsed in either fresh wash water or various types of reused wash waters. The washed leaves were then dried, placed in bags made from special oxygen-permeable films, and stored at 5¡ÆC. The article stated that microbial growth and product quality were monitored at various intervals over 14 days of storage and the results at the end of storage time showed that unwashed control leaves and leaves washed with reused water had higher bacterial counts than those washed with clean water.

The study was first published in HortScience.
Luo, in partnership with Illinois University, has also evaluated the effectiveness of combining a sanitizer with ultrasound treatment for industrial-scale produce washing, with her study demonstrating that this approach could cut bacterial contamination from about 300,000 colony forming units to 10, stated the article.

Another PQSL study by microbiologist Arvind Bhagwat analysed bacterial resistance to different temperatures and its findings were originally published in the April 2008 issue of the Journal of Food Science. Bhagwat's aim, according to the article, was to discover if a lack of oxygen would hinder a bacterium's survival in the human gut. The study was prompted by the fact that manufacturers have been using a type of low-oxygen based modified atmosphere packaging (MAP) to extend the time that bagged salad appears fresh, according to Agriculture Research. Bacteria were applied to fresh-cut lettuce and stored under various MAP conditions for eight days for the study.
Low-oxygen conditions were defined as between 0.5 per cent and one per cent oxygen in a sealed package and regular oxygen conditions were defined as 20 percent oxygen in a sealed package.
The article stated that the results showed that "when stored under extremely low-oxygen conditions and at temperatures of 15¡ÆC or above, bacteria became more resistance to synthetic gastric juice. In comparison, no resistance was induced among bacteria stored under extremely low-oxygen conditions and at temperatures of 10¡ÆC or below"
"The findings also highlight the importance of responsible use of MAP. Proper storage temperature is important to minimizing bacterial adaptability," said Bhagwat.
The PSQL research was published in the USDA's Agricultural Research magazine (July 2008, Vol. 56, No. 6).

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