The disgusting truth about industrial egg production is “it stinks”. Sanitation in such environments stretches the imagination when you think of a million birds trapped in cages in huge shed-type structures called “laying houses” and the tons of fecal material produced daily.
While a high degree of cleanliness may be impractical in an industrial egg production facility, Salmonella in eggs is a major public health threat and sanitation is needed to improve the effectiveness of several other Salmonella interventions.
Egg production in the United States is estimated at 75 billion eggs per year. This enormous volume of production requires a mechanized process, and through many innovations, the industry has been able to maintain an abundant supply of eggs at a relatively low price.
This is good news for consumers, but it comes at a cost to society. There is an environmental impact from these operations which confine vast numbers of birds in a relatively small, enclosed area, and there are important humanitarian issues concerning the care of the animals which has sparked public debate and consumer concerns.
While more Eco-friendly egg-production methods exist and may be an answer to some of the problems of industrial egg production, “factory farming” is the norm and is unlikely to change. The “cage-free” concept sits well with consumers, but those layer hens are still subject to similar inhumane conditions found in the “battery cage” method, and there does not seem to be a correlation between these methods and lower Salmonella incidence.
As a sanitarian, I became familiar with sanitation issues in egg production during a private investigation of the Quality Egg Salmonella Enteritidis outbreak of 2010 with Marler-Clark law firm. That outbreak affected thousands of victims and involved a total breakdown of best industry practices at a facility under the so-called control of the now notorious DeCoster family.
In the Rose Acre Farms Salmonella Braenderup outbreak of 2018, it’s not surprising that the observations by FDA at the facility in North Carolina (Hyde County Egg-Pantego NC) note one of the main issues found at Quality Egg eight years earlier-an uncontrolled rodent infestation.
(For the FDA From 483)
It is not that food safety professionals haven’t learned how to control Salmonella in egg production. In 2009 the USDA through its APHIS branch released a report citing a European study that provided a method for the Prevention, Detection, and Control of Salmonella in Poultry. The methods are believed to have gained acceptance in the U.S. egg industry, but as we see once again outbreaks occur where management fails to ensure that operations follow the required protocols for control.
(For the APHIS report)
Perhaps the most effective way to prevent the transmission of Salmonella through eggs is early detection of Salmonella in egg production. It should be pointed out that Salmonella in whole eggs is the result of trans-ovarian transmission, where the bacteria are deposited in the egg before the shell is formed. This transmission route has important considerations for controls, (i.e., to prevent deposition of Salmonella in the egg we must first and foremost prevent the infection of the laying hen).
As a primary control, breeder stocks must be tested and found free of Salmonella. An infected breeding hen which provides eggs that are hatched into chicks then raised into laying hens could infect a flock. A second important control s the testing of chicken feed; the contaminated feed would provide an ongoing source of infection in a flock.
But even if layers and feed are not infected, the threat of Salmonella in an egg production house might still originate from rodents and flies infesting the chicken litter and manure as it collects under the cages. Vectors and filth can then contaminate feed, mechanized equipment, processing equipment, people, water and environments causing massive cross contamination throughout the operations and thereby perpetuate the infection of many more eggs
Effective rodent and insect control in a layer house take a coordinated effort between plant management and pest control operators. Pest pressure will be greatest when the plant and grounds are not maintained, sanitation is poor, and outer openings are not protected. Certainly, a rodent-free environment would be ideal, but this is practically impossible in a layer house. The goal of the rodent control program should be therefore to reduce the breeding population of rodents to an acceptable number by relying on properly placed and maintained rodent devices to both trap and poison rodents. The vast number of rodent traps and bait stations needed requires a systematic rodent device monitoring program which is well executed and documented. When analyzed, the trends in data from such monitoring can identify an increase in catches and sightings allowing effective intervention to thwart an infestation.
Early detection of Salmonella in a layer house through tests of the wastes that are building up under cages also allows an effective intervention which could include a temporary halt in production. The facility could then remove infected materials and trigger further surveillance, If the infection has spread to the flock, culling would be necessary, and perhaps a product recall could be initiated as a precaution.
Eggs are typically processed by washing them to remove organic material then treating them with antimicrobial treated water. If problems with antimicrobial levels, equipment, environmental sanitation, or water quality are occurring, environmental niches will spread contamination throughout a plant creating a continuous source of exposure.
Maintaining control over the facility environment, the animals, people, equipment, feed, and water are formidable tasks faced by managers of industrial egg production facilities; however, when outbreaks occur, they are widespread and sometimes deadly. Outbreaks result in a significant public health impact, not to mention potential criminal, regulatory or civil action (recall that Quality Egg owners served prison time for their failures). The failure of management to perform due diligence is a troublesome but common theme in many past foodborne illness outbreaks and will likely surface again as a causation factor at Rose Acre Farms.
While Rose Acre Farms and the former Quality Egg operations may be bad actors in the egg industry, the underlying challenge for the industry is to be proactive in identifying and isolating egg suppliers who have an ongoing history of noncompliance. Certainly, these firms are known to the major retail buyers- and to FDA. It may be FDA faces major political or administrative challenges in regulating the egg industry, but this current failure of the food safety system is yet another indication that further change is needed in our food safety programs and that we are still a long way from the risk-based model FDA is hoping the food industry will embrace.
Editor’s note: Bill Marler is managing partner of the food safety law firm of Marler Clark, and he is also the publisher of Food Safety News. Roy Costa has served as an expert witness for Marler Clark in some of the most important food safety cases in the last 25 years.
(To sign up for a free subscription to Food Safety News, click )