Close the hatches. They’re on their way.
We’re talking about rodents, mice and rats, which are formidable enemies of the food industry, especially when autumn brings cooler weather.
Food processors, warehouse managers, restaurant owners and even homeowners know this all too well. After all, rodents look a lot like humans. They are looking for warmth, shelter and food now that the weather is getting colder.
Not surprisingly, a large wave of rodents can be expected with the first frost, warned Jerry Heath of Industrial Fumigant Co, during a recent webinar aimed at food facility owners, managers and their employees.
He also warned that a rodent infestation can be extremely damaging to a food processing facility as it could lead to the closure of the facility if the problem is not addressed quickly and properly. This is especially true when it comes to food safety. In many food recalls, rodent feces is one of the reasons.
That’s not surprising, since rodents are known to contaminate (or consume) about 20 percent of the world’s food supply. Additionally, they can carry more than 60 highly dangerous communicable diseases, according to the Food and Drug Administration.
Some scientists even go so far as to call rodents public enemy No. 1 when it comes to food and beverage processing facilities.
In terms of food safety, Salmonella, Listeria and E. coli are among the foodborne illnesses that rodents can carry.
Foodborne illnesses like these can also cause serious health problems in humans. . . even death. The federal government estimates that about 48 million cases of foodborne illness occur annually – the equivalent of 1 in 6 Americans getting sick each year. And each year, these diseases result in an estimated 128,000 hospitalizations and 3,000 deaths.
Therefore, owners and managers of food processing facilities should ensure that their employees are educated on the importance of being on the lookout for rodent infestations as well as what to do to prevent them. And also what they should do to protect themselves.
A rodent infestation can lead to a recall and the closure of a business if the problem is not addressed quickly and appropriately. This is a major financial blow for the company. For the employees, this means losing their jobs.
Where are the bugs?
Surprisingly, the first line of attack this time of year is not indoors, but outdoors. That’s why Heath lists “exclusion” as the main goal in this battle against rodents.
In other words, many rodents are waiting outside for a way to get in. These may include complexes bordered by fields, wooded areas, shrubs, bark mulch, rivers, creeks or railroad beds.
Each of these environments ensures that mice will be plentiful outside buildings at most times of the year. The extent of favorable conditions in these areas determines the risk of rodent invasions in a building.
Heath said Walmart actually found more rodents coming in with outside deliveries than many other suspicious places. Some even warn not to keep the door open longer than necessary and even then to watch out for any mice running in.
Is it a rat or a mouse
As for the difference between rats and mice, house mice are actually worse pests in buildings than rats. For starters, they are more numerous. Also, because a mouse is so much smaller than a rat, it can find more openings in a building.
They also have a high reproduction rate, which allows larger populations to build up more quickly.
And they can survive on food alone. . . they do not require water, which allows them to exploit more areas in a warehouse or processing center.
Daylight
“If you can see daylight,” the rodents can get in, Heath said.
According to the FDA, rodent parts most commonly enter products after entering facilities through cracks or holes in walls, gaps around doors, windows, as well as through the foundation, roof or ventilation, structural openings and ducts.
Weatherstrips on the bottom of doors are the most common entry point for mice. For this reason, they should be checked regularly for spaces that allow possible mouse input.
They are also attracted to storage areas with high moisture levels where food is not properly sealed, and, in general, areas that are not clean, organized and free of trash. [or] waste.
“Unprotected openings will allow access from other places,” Heath said.
It is also important to have plenty of waste containers or compactors with lids to discourage rodents.
Employee training also comes into the picture. Workers must make sure the waste gets into these containers and doesn’t spread everywhere, Heath said.
“And if you can see where you are experiencing pressure and problems, you should set traps outside in those areas,” he advised. “You have to intercept them outside before they come in.”
A row of bait stations can be effective.
A rodent bait station is a small, usually plastic box with a hole through which pests can enter. The box contains a highly poisonous bait, so any rodents that consume the bait will die. Many rodents also take the bait back to their nest, where it is shared with others.
These bait stations are very effective both indoors and outdoors. Because they are tamper- and weather-resistant, they can be safely placed outdoors without the risk of non-target animals or even curious children coming into contact with the poison. And unlike other capture systems, the poison does not escape and is therefore safely collected.
If you have young children or pets, a station is also a good alternative to other pesticides or toxic treatments. Some other treatments leave behind residues that can be dangerous to non-target animals and humans, while in a bait station the poison is safely contained.
Yep, there’s a mouse here
If a mouse is spotted indoors, lay down glue traps and isolate the area where the mouse was seen. For example, maybe he walked under some pallets. If so, surround the pallets with the adhesive traps.
“It’s amazing how you can catch them like this,” Heath said.
Regular snap traps can also be effective. When you use them,
Identify high traffic areas and focus on areas where you have seen mouse droppings or other signs of a mouse infestation. Also place the traps correctly. To increase the chances of a rodent encountering the trap, place the traps perpendicular to the wall, with the baited side facing the wall.
The number, type and placement of rodent control products should change each week to eliminate an infestation.
These changes are necessary to eventually entice each mouse to interact with and bind to one of the devices. Only this approach, along with correcting contributing conditions such as cleaning up food spills, reducing hiding places, and eliminating rodents, will produce the desired results.
Rodenticide baits need to be renewed or replaced. The larger the initial population, the longer it will take to achieve total control. It will take time to entice each mouse to communicate with and bind to one of the control devices.
Traps need to be maintained, replaced, updated and moved. Mouse carcasses should be discovered and removed.
Gloves should be used and hands should be washed thoroughly afterwards.
What about fumigation?
Disinfectants differ from aerosolizing pesticides because they allow penetration into equipment, packaging, products and raw materials.
Fumigation treatments rely on the strength and effectiveness of a fumigation gas in sufficient concentration and exposure time to eliminate the target pests, including rodents. Fumigants differ from atomizing pesticides in that the fumigant is in a gas phase and not in aerosolized liquid droplets. The gas phase of disinfectants allows penetration into equipment, packaging, products and raw materials.
According to IFC, fumigation can be an effective way to meet a company’s food safety needs.
Trailers outside
Some processing centers and warehouses have trailers outside that are used to transport things like food waste or even livestock feed. But Heath warned that some of these are dilapidated old caravans, infested with rodents.
“That is completely unacceptable,” he said. They should be ‘food-grade trailers’. And they should be inspected before food waste or animal feed is put into them.
This also applies to trailers used for the export of foodstuffs.
Recalls
Time and time again, food memories make the news. In the spring of 2022, Dollar Tree Distribution Inc. for example, recalled a number of items, including human food, due to a serious rodent infestation at an Arkansas distribution center.
According to the Food and Drug Administration, after the facility was decontaminated in January 2022, more than 1,100 dead rodents were found in the facility.
A review of the company’s internal records also revealed that more than 2,300 rodents had been collected between March 29 and September 17, 2021, demonstrating a history of contamination,” the FDA public alert said.
In February 2024, Family Dollar Stores LLC pleaded guilty to holding food, drugs, medical devices and cosmetics under unsanitary conditions in connection with a rodent infestation at the company’s distribution center in West Memphis, AR.
This action by the FDA marked an important chapter in the history of food safety. The company, Family Dollar, a subsidiary of Dollar Tree Inc., entered into a plea deal that included a penalty of a fine and forfeiture totaling $41.675 million – the largest criminal fine ever imposed in a food safety case.
Subsequently, Wehah Farms of Richvale, California, recalled 4,600 cases of Lundberg Family Farms Sustainable Wild Blend Gourmet Rice in May 2024 because the rice may contain a foreign object that appears to be of rodent origin, according to the FDA.
The recall first occurred in May, but then the FDA updated the notice to say the recalled product could cause temporary or reversible health effects.
Food recalls could be widespread. In this case, the contaminated rice was distributed in California, Oregon, Wisconsin, Maine, Florida, Arizona and New Hampshire.
“When consumers go to the store, they have the right to expect that the food and drugs on the shelves have been stored in clean, uncontaminated conditions,” said Benjamin C. Mizer, acting deputy attorney general of the FDA. “When companies betray that trust and violate the laws designed to protect consumer safety, the public should rest assured that the Department of Justice will hold those companies accountable.”
It’s not rocket science
Rodent control comes down to perseverance and creativity. Although controlling a mouse infestation will take more than a day or a week, daily follow-up inspections are the key to success.
Go here for information on specific rodent control products.
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