The Center of Disease Control reports that more than 48 million Americans—roughly one-sixth of the population—are infected with a foodborne illness every year. Of these, more than 125,000 are hospitalized and about 3,000 people die every year because of a foodborne illness. The CDC also discovered that nearly 70 percent of foodborne illnesses and more than 50 percent of foodborne illness deaths come from two categories of food: produce and meat/poultry, two of the most common food groups prepared in restaurants and homes.

A foodborne illness is defined as a sickness that is “caused by consuming food contaminated with pathogenic bacteria, toxins, viruses, prions or parasites.” Pests, such as rats, cockroaches, and flies, are a driving force behind how bacteria is spread in homes and restaurants. The U.S. Food & Drug Administration, the department aimed at promoting and maintaining food safety, even set forth an entire set of basic guidelines on the conditions pests thrive in and how business and homes should avoid hosting these conditions.

“Recent scientific advances have increased the precision of the scientific criteria used to interpret the regulatory significance of adulteration (failing to meet government standards) involving insects, rodents, and other pests in foods,” the FDA stated before reporting on the conditions of pest contamination.

Now sure, pests look gross, but how exactly do they spread diseases? And what pests should you watch for?

Types Of Pests That Harbor Diseases

A leading food safety magazine article, written by high-ranking members of the National Pest Management Association, highlights four main types of pests that spread foodborne illnesses in restaurants, factories, and your home.

Cockroaches

If you didn’t think cockroaches were the worst creatures on the planet just by their appearance, they also carry tons of bacteria that cause diseases like:

  • Salmonellosis
  • Gastroenteritis
  • Dysentery
  • Typhoid Fever
  • The Plague

“Cockroaches can spread 33 different types of bacteria,” NPMA Vice President Missy Henriksen said. Air containing cockroach feces can also cause asthma attacks and allergic reactions.

The six-legged critters don’t spread diseases through biting people, but rather they contaminate things like food and countertops through simple contact. Their excrement, such as saliva and droppings, carry the diseases, and then simply walking over a surface can contaminate the area. Though cockroaches aren’t the primary reason for the infection of foodborne illness, “they play a supplementary role in the spread of some diseases,” the World Health Organization reported.

Rodents

Rodents are a highly diverse species, containing thousands of types of rats and mice. They also cover the greatest area of any pest that carries foodborne illness because of how many droppings they produce—a single rat can produce up to 25,000 droppings per year. Rodent droppings carry various parasites and pathogens that are the root of over 35 diseases including (courtesy of the CDC):

  • Plague
  • Leptospirosis
  • Tularemia
  • Salmonellosis
  • Omsk Hemorrhagic Fever

It’s also been reported that rodents contaminate or destroy enough food to feed 200 million people per year. Rodents have also been a leading killer of humans for thousands of years due to the amount of deadly outbreaks that have started because of diseases stemming from rodents.

Rodents were recently the cause of an outbreak in Florida of a potentially deadly parasite in food called rat lungworm. The parasite was spread through snails eating rat droppings, which carry the parasite. Once the snails, along with slugs and other crustaceans, became infected with the parasite, they carried the disease and spread it to humans through consumption, whether intentionally (eating at restaurants) or unintentionally (through the lack of cleaning food snails came in contact with).

Flies

Flies, such as the common housefly and fruit flies, carry the most diseases of any pest—more than 100 varying pathogens. They also spread diseases very easily because of how free-flowing they are.

“Flies can spread diseases because they feed freely on human food and filthy matter alike,” the WHO said. “The fly picks up disease-causing organisms while crawling and feeding. Those that stick to the outside surfaces of the fly may survive for only a few hours, but those that are ingested with the food may survive in the fly’s crop or gut for several days.”

With plenty of food and waste in restaurant and your home, it’s prime feeding ground for flies, which can just as easily pick up a disease from one place and transfer it to food in a matter of seconds.

Stored Product Pests

And then there are “stored product pests.” This is an overarching term for pests that “include several beetles, moths, and a mite that can infest whole grains or processed foods,” the College of Agriculture at the University of Kentucky defined.

These pests often feed on foods like rice, flour, wheat, cereals, powdered sugars and processed foods, and kernels of corn. Stored product pests are often accidentally ground up into these foods at food plants and factories; or the pests can shed carcasses and leave them behind to be ground up in food. These pests can carry diseases like Lyme disease, and their eggs can survive and hatch inside varying types of food.

How to Stop Pests From Getting Inside

The first step in decontaminating an area infested with foodborne illness-carrying pests in making sure they stop entering an area in the first place.

Pests have various ways of getting in places pending on their size, but the primary way is the most obvious: through open windows and doors. Smaller pests like flies and cockroaches can also enter houses through small cracks and openings in walls and unsealed windows. You can easily limit the entry ways for pests by keeping windows and doors closed as often as possible. If you do keep windows open, it’s imperative to have small-holed screens to protect from pests entering that way.

Rodents are especially sneaky, traveling above and below the house and entering through holes that way. It’s important you check below and all around the house at any level for holes or cracks.

It’s also advised you trim branches and bushes that hang over or lead directly to the house. Rodents are known to jump from branches to roofs, where they can find access through chimneys or other small openings not directly known to you. Making sure your yard is clean and free of any dense, unsanitary spaces to live is also a good start in preventing rodents from getting into your house.

Decontamination And Prevention

But what if pests do get in? Once the area is clean, how do you decontaminate the area and maintain it?

A common thread through all pests is their love for feasting on garbage. Flies, rodents, cockroaches, you name it—they all feast on and spread foodborne illness through contact with trash. An important step in decontaminating a space that contains food is making sure the garbage is in metal or plastic trash cans—remember to line them with plastic garbage bags!—away from prepared food, and that it’s taken out once it’s full. The longer trash is left around, the higher chance pests will be attracted to your area, thus inviting foodborne illness into your space.

It’s also crucial you maintain a sanitizing and cleaning schedule. Trash isn’t just found in a trash can—it can be found all over your home or restaurant, especially in the kitchen. Cockroaches are feast on grease and sweet foods, so cleaning residue off stoves and countertops every night is an important step in making sure pests don’t have anything to feed on in your house.

“The importance of limiting fly breeding by employing proper sanitation is of crucial importance,” a government study reported. “It is clear that without the use of proper sanitation methods, flies will continue to replicate and disperse from adjacent areas and will undermine any control measures.”

Pests desperately need water to live, so it’s doubly important to crack down on water leaks and standing water. Leaks can come from pipes in the wall or visible pipes and faucets, and you need to make sure you dry up any areas with standing water, like around sinks and wash rooms.

Keep your area as cool as possible to prevent inviting pests to an area where they can thrive and spread disease.

Many pests like flies and cockroaches need to breathe through their bodies, so there are homemade solutions and sprays that can help with immediate prevention (or elimination) of pests. Mix water and soap in a spray bottle if you want to avoid using chemicals harmful to you and your food. You can also mix apple cider vinegar and a couple drops of soap in a dish to help trap fruit flies. These solutions get stuck on the pests’ bodies and essentially suffocate them.

Traps are also useful ways of preventing pests—and therefore foodborne illnesses—from spreading around an area. Rodent traps can be places inside and around your home or restaurant. Cockroach traps should be strategically placed, mainly near areas where water flows or sits the most like sinks and floor drains. You also should set up traps near small cracks in the wall (if you haven’t filled them), cabinets, and pantries, because the little pests can wiggle their way through openings in doors.

Cockroaches and flies also thrive in hot and humid areas. It has been reported that “many of the pathogens that cause water- and food-borne illnesses in dwellers are sensitive to climate parameters, including increased temperature, changing precipitation patterns, extreme precipitation events, and associated changes in seasonal patterns in the hydrological cycle.”

Keep your area as cool as possible to prevent inviting pests to an area where they can thrive and spread disease. The book’s report report also drives home the need to seal any cracks or holes in walls and windows to prevent standing water from entering your area.

If infestation is out of control, or you need help pinpointing how pests are getting into your home in the first place, it’s imperative you call experts to help you find the best way to decontaminate your space.

Additional Reading

The following guides will help you further understand how to control certain pests within your home: