Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis are the two most frequently identified causes of egg-associated disease in industrialized countries. In Australia, a comprehensive review of egg-associated outbreaks has not been previously undertaken.
Methods: Using a national register of foodborne outbreaks, we undertook a descriptive review of egg-associated outbreaks between 2001 and 2011. Included in our review was additional detail from the findings of trace back investigations conducted to the farm level. Evidence classifications were developed and applied to each outbreak based on descriptive and analytical epidemiology, food safety investigations, and microbiological testing of clinical, food, and trace back-derived samples.
Results: Over the study period, the proportion of foodborne Salmonella outbreaks linked to eggs increased significantly (p < 0.001). In total, 166 outbreaks were identified, with 90% caused by Salmonella Typhimurium. The majority of outbreaks were linked to commercial food providers, with raw egg use the major contributing factor. These events resulted in more than 3200 cases, more than 650 hospitalizations, and at least 4 deaths. Fifty-four percent of investigations used analytical epidemiology, food microbiology, and trace back microbiology to demonstrate links between human illness and eggs. Trace back investigations identified S. enterica indistinguishable from outbreak-associated clinical or food samples on 50% of sampled egg farms.
Conclusion: Effective control of egg-associated salmonellosis remains a challenge in Australia, with Salmonella Typhimurium dominating as the causative serotype in outbreak events. Although outbreaks predominantly occur in the settings of restaurants, the high recovery rate of indistinguishable Salmonella on epidemiologically implicated egg farms suggests that further efforts to minimize infection pressure at the primary production level are needed in Australia.
Salmonella Typhimurium and Outbreaks of Egg-Associated Disease in Australia, 2001 to 2011
Foodborne Pathogens and Disease; March 2016; DOI: 10.1089/fpd.2015.2110
The editorial board of The Des Moines Register writes that if there’s one lesson to be learned from the 2010 salmonella outbreak that originated in Iowa and sickened thousands of consumers nationwide, it’s the high cost of failing to properly regulate egg production.
But what constitutes proper regulation?
What constitutes proper audits and inspections?
How can consumers choose?
Jack and Peter DeCoster, who were criminally charged for the way they ran the Quality Egg operation in Iowa, were bad actors, as the Iowa egg industry now admits. But what sort of regulatory system do we have that allows scofflaws to not only flourish but also become some of the industry’s biggest players?
That’s a question our governor and state legislators have steadfastly, and very deliberately, refused to address. Still, it has to be asked, particularly in light of the recent revelations that the Iowa Department of Agriculture and Land Stewardship indefinitely suspended its inspection of egg production facilities last year to eliminate any risk of inspectors spreading the bird flu virus.
After the 2010 salmonella outbreak and shortly before leaving office, Iowa Gov. Chet Culver proposed a series of reforms aimed at addressing five vulnerabilities in Iowa’s egg production regulations. None have been acted upon by the Branstad administration.
Among the proposed reforms:
More stringent state oversight of the smaller egg farms — those with fewer than 3,000 laying hens — that are exempt from federal regulations.
State-mandated reporting, by both testing laboratories and egg producers, of positive tests for salmonella enteritidis.
Accreditation and certification standards for laboratories that perform testing for salmonella.
Creation of a state-mandated salmonella detection and prevention program, with minimum training and competency standards for the staff.
Creation of a new funding stream to support the implementation of a comprehensive, statewide egg-safety program.
Internal and external food safety audits are conducted to assess the safety and quality of food including on-farm production, manufacturing practices, sanitation, and hygiene. Some auditors are direct stakeholders that are employed by food establishments to conduct internal audits, while other auditors may represent the interests of a second-party purchaser or a third-party auditing agency. Some buyers conduct their own audits or additional testing, while some buyers trust the results of third-party audits or inspections. Third-party auditors, however, use various food safety audit standards and most do not have a vested interest in the products being sold. Audits are conducted under a proprietary standard, while food safety inspections are generally conducted within a legal framework. There have been many foodborne illness outbreaks linked to food processors that have passed third-party audits and inspections, raising questions about the utility of both. Supporters argue third-party audits are a way to ensure food safety in an era of dwindling economic resources. Critics contend that while external audits and inspections can be a valuable tool to help ensure safe food, such activities represent only a snapshot in time. This paper identifies limitations of food safety inspections and audits and provides recommendations for strengthening the system, based on developing a strong food safety culture, including risk-based verification steps, throughout the food safety system.
Jason Clayworth of The Des Moines Register reports that Iowa, the epicenter of a nationwide salmonella outbreak that sickened thousands of people nearly six years ago, has suspended its egg facility inspections to guard against a recurrence of bird flu. While the risk may be slight, state agriculture officials say they fear that inspectors might spread the virus from one flock to another as they visit egg facilities.
Government officials and egg industry supporters contend that suspending inspections, which stopped almost a year ago, has not compromised food safety. Farmers are still expected to follow safety regulations, some put in place after the 2010 egg recall.
But critics say the lack of inspections in the nation’s top-producing egg state jeopardizes food safety for biosecurity and leaves the precautions up to corporate farm operators. And they point to the most recently available reports from federal or state inspections, done before the checks ended, to emphasize why such oversight is necessary.
Those records show:
STRAY ANIMALS: Multiple incidents of stray animals getting inside poultry houses, including one site where “approximately eight” frogs were found. Contact between poultry and other animals that can carry disease is forbidden in the facilities. That includes amphibians, which can carry salmonella and cause serious illness to humans.
REFRIGERATION: Not washing or storing eggs at appropriate temperatures at multiple facilities.
BOTCHED TESTS: Improper or no testing for salmonella as required by federal rules in at least 14 sites.
RODENTS: Evidence of rodent infestations, including
“This is jaw-dropping. I just don’t know what else to say,” said Marion Nestle, a professor of nutrition at New York University and an author of books on food safety. “The inspectors are turning up potential hazards. Why anybody would tell you with a straight face that suspending these inspections is no big deal is beyond my comprehension.”
Oscar Garrison, a food safety executive for United Egg Producers, said stopping bird flu also impacts human health. The virus led to the destruction of more than 31 million chickens, turkeys and other birds in Iowa last year.
Garrison said he believes that suspending the inspections was an appropriate step, given the context of the bird flu catastrophe.
Other top-producing egg states have either continued to inspect egg producers during the outbreak or stopped temporarily and later resumed them, the Register found. Ohio, the second-largest egg-producing state, and Texas, the nation’s fifth-top egg producer, resumed their inspections late last year. Indiana, the third-largest, continued its inspection throughout, as did fourth-largest Pennsylvania, state officials said.
Pennsylvania officials changed their protocol after the outbreak, instructing inspectors to wait at least seven days between inspection visits to different farms. Such an alternative — or requiring inspectors to wear biosafety gear — is more sensible than suspending inspections entirely, said William Marler, a Seattle attorney whose firm represented more than 100 victims of the 2010 nationwide salmonella outbreak whose origins were traced to Iowa.
“Given the black eye Iowa’s egg production got in 2010, it just seems shortsighted to suspend the inspections,” Marler said. “It sends a completely wrong message to consumers.”
The government reported that at least 1,939 cases of illness were likely associated with the outbreak. But some believe the number to be more than 50,000 people, citing Centers for Disease and Prevention reports that estimate that for every reported illness, more than 38 go unreported.
Austin “Jack” DeCoster and his son, Peter, were sentenced in April to 90 days in jail and fined $100,000 each for their role in the outbreak.
Their trials brought to light what federal officials said was a deliberate and routine effort to avoid proper health regulations. That included falsifying paperwork to a firm that inspected the plant. On the eve of each audit, workers were given blank, signed audit forms and told to fabricate data for the report, prosecutors said.
After reports of human illness, regulators made findings that included rodent infestations and as much as 8 feet of manure beneath some of the facilities.
The recall come after the Ohio Department of Agriculture collected samples that tested positive for Salmonella. Kenneth Miller Farms supplies Lucky’s Taproom with eggs, the popular Oregon District restaurant had to shut its doors earlier this month after dozens of customers became sickened. Tests later revealed that mayonnaise made locally tested positive for Salmonella.
We examined trends in SE foodborne outbreaks from 1973 to 2009 using Joinpoint and Poisson regression. The annual number of SE outbreaks increased sharply in the 1970s and 1980s but declined significantly after 1990.
Over the study period, SE outbreaks were most frequently attributed to foods containing eggs. The average rate of SE outbreaks attributed to egg-containing foods reported by states began to decline significantly after 1990, and the proportion of SE outbreaks attributed to egg-containing foods began declining after 1997.
Our results suggest that interventions initiated in the 1990s to decrease SE contamination of shell eggs may have been integral to preventing SE outbreaks.
The rise and decline in Salmonella enterica serovar Enteritidis outbreaks attributed to egg-containing foods in the United States, 1973–2009
Five people were admitted to hospitals, although health officials said they don’t know whether anyone remains hospitalized. The restaurant shut down Monday, Feb. 29. Health officials expect the number of confirmed salmonella cases to rise as test results are completed, Steele said.
Drew Trick, the owner of Lucky’s, said Monday that the eatery will never make its mayonnaise in-house again. On the tap room’s Facebook page, Trick wrote, “Well, it seems our efforts to source locally and make our food from scratch has failed our customers and ourselves. Know that we are doing all that is possible to rectify the situation and eliminate the chance of this happening again.”
Lucky’s, at 520 E. Fifth St. in Dayton’s Oregon District, will remain closed “for an unknown period of time,” Trick wrote, but hopes “to open with a clean bill of health very soon.” The restaurant and craft-beer bar had been gearing up for its 5th anniversary celebration this week.
A table of raw egg-related outbreaks in Australia is available at:
Ken Klippen of the U.S. National Association of Egg Farmers writes in support of Will Coggin’s letter to the editor on the Massachusetts ballot initiative on caged layers producing eggs. The group I represent, The National Association of Egg Farmers, is in support of free choice for eggs from different production systems, but the ballot initiative will eliminate that free choice.
As it relates to food safety, every egg farmer knows that eggs laid on the same ground where manure is located increases the likelihood of contamination.
The Coalition for Sustainable Egg Supply, a group of scientists investigating the different production systems for eggs, finished their two-year study of the available research including food safety. The conclusions from their analysis of the research is that eggs produced in caged environments had less fecal contamination compared to cage-free eggs. This is logical since cages allow for the eggs to be removed from the environment of the hen compared to cage-free, where the eggs come into contact with manure. Any reasoning person would conclude that keeping eggs clean and away from manure is better from a food safety perspective.
Caged eggs allow for cleaner eggs.
The scientific articles that support this claim are below:
1) The Journal Poultry Science in 2011 [90, pp. 1586-1593] published “Comparison of shell bacteria from unwashed and washed table eggs harvested from caged laying hens and cage-free floor-housed laying hens.”
This study found that the numbers of bacteria on eggs was lower in housing systems that separated hens from manure and shavings.
2) The Journal Food Control published a study June 17, 2014, entitled “Microbiological Contamination of Shell Eggs Produced in Conventional and Free-Range Housing Systems.” The conclusions state, “Battery caged hens are standing on wire slats that allow feces to fall to a manure collection system beneath the hens. Conversely, free-range hens laid their eggs in nest boxes on shavings and the eggs remained in contact with hens, shavings and fecal material until they are collected. The longer contact time with free-range hens, shavings and feces would explain the higher enterobacteriaceae counts (pathogenic bacteria) on free-range eggs as compared to battery caged eggs.”
One of the letters to the editor claims that caged layers increases salmonella, citing a government survey. This is not true. It’s not even logical when considering the federal agency responsible for food safety has issued regulations to protect the consumer. The Food & Drug Administration has issued the regulation entitled Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and Transportation (21 CFR part 118) on July 9, 2009, requiring shell egg farmers to implement measures to prevent SE from contaminating eggs on the farm. If caged environments increased salmonella, it’s inconceivable that FDA would issue regulations governing the production of eggs in caged environments.
Those hens laid 550 million eggs tainted with a toxic strain of Salmonella enteritidis, which in turn ended up on grocery store shelves. The eggs were broken into skillets, whisked into mayonnaise, and ended up sickening as many as 6,200 Americans in what would become the largest egg recall in U.S. history. The U.S. Department of Agriculture and the Food and Drug Administration quickly passed laws to reform egg safety—but not before consumers had seen the crack in the industry’s veneer.
TEN Ag Tech, a Southern California–based startup aims to take the existential crisis out of your egg purchase. The tech company seeks to keep the egg industry accountable in two ways. First, it offers mobile-based apps that increase transparency on farms by monitoring human behavior—i.e., keeping track of who enters and leaves a hen house. Second, it engraves each individual egg with its own (nontoxic, naturally) gold laser barcode. Input that barcode onto the Naturally Smart Egg website, and you’ll instantly know everything about that egg’s origins: the breed of hen that laid it, the production method that spawned it (cage-free, traditional caged production, or free-range), and the moment it was packed within 180 seconds.
If this is all beginning to sound like a certain Portlandia skit—you know, that one where the couple interrogate their waitress about Colin, the chicken they will be enjoying—then you’re on the right track.
It’s that, plus data. TEN Ag Tech seeks to “reconnect consumers to the farms that feed them,” according to its website. Since last July, consumers have been buying the company’s Naturally Smart eggs on the shelves of Chicago’s high-end Mariano’s grocery stores, a division of Kroger.
TEN Ag Tech’s vision is not limited to eggs: In February, the company will debut its traceable technology for coffee and meat. The goal is to prevent foodborne illness debacles like the recent outbreaks at fast-casual chain Chipotle. “As monoculture grows, companies like Chipotle are creating alternative realities, fresh food, local foods coming from local places,” says Jonathan Phillips, the company’s president and CEO. “The question is: When you’re dealing with 40,000 farms, how on Earth do you ensure that they’re all producing food for you safely? Our tech begins to solve that problem.”
But when it comes to helping us avoid outbreaks in the first place, this kind of data may be useless, says Ken Anderson, a poultry-extension specialist at North Carolina State University who focuses on egg processing, production, and safety. That’s because in most cases, contamination takes place after the production process, whether in a grocery store, a restaurant, or in your own kitchen. “It’s workers at a grocery store. It’s consumers opening up the egg cartons. It’s people transferring eggs to plastic cartons in their fridge,” says Anderson. “Those little things all add up and add a potential for contamination totally separate from how the eggs were produced.”
Woolworths has pledged to keep eggs in refrigerated cabinets as it continues a nation-wide revamp of its stores.
It is understood dozens of Woolies outlets have had new cabinets installed in the past year, allowing stores to keep fresh eggs chilled below seven degrees, which helps prevent the spread of the harmful salmonella bacteria.
Coles, however, would not disclose if any of its stores would keep eggs refrigerated in response to these calls, prompting shoppers to criticise the company across its social media platforms.
“I will be buying my eggs in Woolworths until you return to displaying them in a chilled area,” one shopper wrote on the company’s Facebook page.
A NSW personal trainer wrote how he had stopped buying eggs from Coles while another shopper pointed out: “It even says on the carton: keep refrigerated.”
The shopper revolt came as another expert joined calls urging stores from large supermarkets to small grocers to be part of an unbroken chain of cold storage for eggs.
Professor Peter Collignon, an infectious diseases expert at Australian National University’s medical school, said eggs must be treated just like raw meat and kept in a refrigerator at all times.
“I’m always surprised by the lack of anxiety about this,” he said. “We ought to make the product safer, and we do that by refrigerating it, even at the supermarket.”
Coles declined to comment on Sunday.
It had previously released a one-line statement – “Coles adheres to all health and safety regulations regarding egg storage” – and responded to complaints on social media by denying it was an issue.
Peter Scott, an associate professor at the University of Melbourne’s veterinary school, said keeping eggs chilled in all retail stores would not make a big difference to rising salmonella infection rates.
“For the limited time the eggs are stored at the supermarket unrefrigerated it is, black and white, not significant,” he said.
Dr Scott, who also works as a consultant for the poultry industry, stressed that poor practices at farms, where “dirty eggs” are graded and used when they shouldn’t be, combined with poor food-handling practices, particularly in catering or at restaurants, have been the main culprits behind large outbreaks of the food-borne illness.
“You need two consecutive events: an egg contaminated with salmonella and then the [growth] in a raw egg dish,” he said.
“When [eggs] are made into one of these raw egg products, the replication of salmonella is very dramatic, and that’s where all the food poisoning is coming from.”
He said it was crucial for supermarkets to think about cold storage and egg-related salmonella prevention because the risk of an outbreak, leading to serious illness and hospitalisation, can arise at any point from the farm to the home.
“It is a priority. We’ve seen lots of outbreaks. We should be doing multiple things to try and prevent salmonella occurring.”
Under food safety laws, Australian eggs are washed, inspected for cracks, graded and kept in cool rooms on farms before being transported in refrigerated trucks to reduce the risk of bacterial survival.
But Brian Ahmed, president of the egg group at the Victorian Farmers Federation, said keeping eggs refrigerated in supermarkets remains the “missing link” in the food safety chain.
“It should be treated exactly like raw meat – don’t look at an egg any different way,” he said.
Connor Thomas, adjunct senior lecturer in microbiology at the University of Adelaide, also urged grocery stores to keep eggs in a cool environment.
“That way you minimise the growth, increase the storage time, and minimise the risk,” Dr Thomas said.
The calls come as the rate of salmonella infections rises across the country, with up to 40 per cent of cases linked to contaminated eggs.
In 2015 there were 58 cases per 100,000 people in Victoria, twice the infection rate of 10 years ago, health department data shows.
Food Standards Australia New Zealand last updated egg safety laws in 2011, but left out a retail requirement for cool storage because it concluded temperature was not a factor in spreading salmonella here if eggs are clean and intact.
A spokeswoman said the strain of salmonella present in Australia cannot grow on egg shells, though it could contaminate other foods or get inside the egg when its protective membrane breaks down or the egg is cracked.
“It was acknowledged that refrigeration during retail storage may enhance the quality of eggs,” she said.
“However, this option was excluded early in the standard development process due to the nature of egg shell contamination in Australia and the substantial cost of implementing such an option.”
But Dr Thomas said eggs have been continually implicated in illness and it’s difficult to predict when an outbreak is going to happen, so it is vital to maintain a chain of food safety protection.
Brisbane likes to think of itself as a bloomin’ metropolis (sorta like the onion), but its food safety politics are based in the old west, with its voluntary disclosure of restaurant inspection reports – 2 stars out of 5, I just won’t post it – and ridiculous number of raw-egg based Salmonella outbreaks.
In Feb., 2015, 254 people, mostly state school principals, fell ill and 24 people were admitted to hospital after eating at an education conference at the Brisbane Convention and Exhibition. A subsequent meeting sickened a few more people.
In Nov. 2015, The Courier-Mail reported that a kitchen stick blender contaminated with Salmonella was the source of the outbreak.
Documents showed that investigators examining the outbreak found bacteria on several kitchen utensils, with that bacteria “incubated’’ during the cooking process.
Test results from the investigation showed the people who fell ill were sick with the same strain of salmonella found on a kitchen stick blender “which demonstrates the source of the outbreak”.
The documents rule out the possibility the outbreak was caused by eggs being contaminated before they arrived at the convention centre.
“(Redacted) suggested that if the eggs were contaminated when they arrived, that this was the cause, however I advised … that poor cleaning and sanitising of the stick blender was the ultimate cause,’’ the documents say.
“(Redacted) questioned why the Sal. was not killed during the cooking process of the bread butter pudding. I advised that the QH microbiologist suggest that 140deg was not hot enough to kill Sal, but rather it was an incubation temp.’’
Brisbane City Council is now considering prosecuting the operators, with a decision due by the end of this year.
Today it was announced the Brisbane Convention and Exhibition Centre will avoid prosecution after an investigation found no evidence the eggs that had been identified as a possible source of the outbreak were, in fact, responsible.
A Brisbane City Council investigation has found there was insufficient evidence to support a prosecution against the BCEC.
Brisbane lifestyle division chairman Krista Adams said a review of the investigation had found the prospect of a successful prosecution against the BCEC, which would cost ratepayers about $400,000, was “poor”.
“Council commissioned an independent review of the investigation which found that not everyone who tested positive for the salmonella strain consumed the suspect foods, which cast doubt as to the origin of the contamination.
Have any of you ever heard of cross-contamination?
A council spokesman supplied the following summary of the council’s legal advice:
There is no evidence that the eggs used by BCEC in the preparation of the suspect food were contaminated.
While a possible source of contamination may have been the stick blender, there is currently no evidence that the stick blender was used for the creation of the suspect food.
There is no evidence to discount the possibility that the stick blender was used in the preparation of other food on the same day which was not contaminated.
There is insufficient evidence to prove beyond reasonable doubt that the contamination was in food prepared and served to the attendees by BCEC at their respective functions.
All of the evidence shows that BCEC has an exemplary record in keeping its kitchens clean and free of contamination and using proper handling and processing techniques to appropriately minimize contamination risks.
A court is more likely to find that the contamination resulted from a factor or factors beyond the reasonable control of the BCEC.
Bullshit, bullshit, bullshit.
Yes, Brisbane is still a cow town but we’re not that dumb.
As I’ve said from the beginning, if BCEC wants anyone’s business, they should come clean and make a full public accounting of the dishes and ingredients served to principals instead of some legal nonsense with council.
It’s a simple thing: were raw eggs used in any of your sauces or dishes?
“Caterers, meal providers and food service organisations are encouraged to research and ensure food comes from reputable sources where stringent food safety protocols are in place,” he said.
“Even when your own safety procedures are by the book, when it comes to the health of your guests and your ongoing reputation, it is important to be confident about the product you are serving.”
O’Hara said Sunny Queen prides itself on its quality assurance and food safety programs, and recommends that customers ask their suppliers detailed questions about their QA protocols.
He said manufacturers and suppliers should be transparent about their food safety procedures.
“Sunny Queen is proud of its quality management system, which includes sanitation and cleaning procedures, pest control programs, precise cooking protocols, microbiological testing and traceability systems.
“Sunny Queen Meal Solutions uses real eggs, laid on Sunny Queen farms, and they are all fully cooked or pasteurised, eliminating the need to use raw eggs so real egg dishes can be served with confidence.
“Food safety doesn’t have to be daunting, it just needs diligence. Eggs are an incredibly versatile, nutrient-rich food source, making them the perfect choice for meal providers and caterers.”