We’ve all experienced this predicament before: you’re at a BBQ, swatting insects off your meal, when you see one has landed on your sandwich. Does a bug buzzing about your food actually offer any health hazards, despite the fact that it can be annoying?
The University of Kentucky’s Zachary DeVries, PhD, assistant professor of urban entomology, explains what potential harm can result from a creepy-crawly landing on your dish and what to do if one does.
Numerous Pathogens are Transported by Insects
Everything you can think of can be carried by flies and other insects, according to DeVries.
The problem, however, is not the bug per se, but rather the location in which it has been buzzing. For instance, you’ve probably observed flies hanging around excrement frequently. According to the University of Sydney, insects like flies are drawn to unpleasant things like decomposing animals and plant waste, which can contain a variety of viruses and parasites.
The two creatures that enter our food most frequently are flies and cockroaches. “Both have been found to carry things like salmonella, E. coli, cholera, and typhoid fever,” DeVries claims.
Pathogens can be transferred by insects to food.
The issue is that these pests might transfer infections to your food. According to DeVries, this transfer takes place via mechanical gearbox.
This is how that procedure looks:
The germs spread to an insect's feet or body through touch when it comes into contact with a pathogen (for example, when it lands on an animal carcass or a trash can).
The infection is then transferred to your food (or a food preparation surface) when the insect touches down on your plate.
To put it another way, when a fly walks across your sandwich, its tracks may carry bacteria and other pathogens.
But it only gets worse. According to DeVries, flies can transmit infections through vomit. According to the University of Sydney, because they lack teeth, they spit up spit that contains unique enzymes that allow them to break down and consume food.
Even worse, according to DeVries, flies frequently poop on your food. Additionally, both defecation and regurgitation might bring germs to your meal.
What if an insect deposits eggs on your food? According to Devries, insects’ “eggs are unlikely to carry pathogens” since they typically carry disease-causing germs on their legs and feet (i.e., on the outside of the body). Phew.
If You Eat Contaminated Food, You Could Get Sick
We now understand that bugs can introduce germs, viruses, and parasites into food. But how likely are you to get these pathogens?
According to DeVries, “This all depends on a variety of factors,” including the following.
What kinds of microorganisms or other potential pathogens might be present in the environment (e.g., availability of trash cans, sewers, etc.)
length of time the bug was exposed to the pathogen sources, such as sewage, rubbish, etc.
How much pathogen was transferred from the pathogen source to your food by the bug
How long the insect was in contact with your food
length of time the infection has been "growing" on your food
What temperature the food was kept at after being exposed to pathogens
According to the University of Sydney, an insect has a greater chance of contaminating your meal with germs the longer it is in contact with a pathogen source and your food (and the higher your risk for potential health problems).
Furthermore, certain environmental factors may provide these microorganisms even more chances to proliferate. According to the USDA, the “danger zone” is a temperature range between 40 and 140 degrees Fahrenheit that might be a favourable environment for harmful bacteria to grow and lead to foodborne illness.
Devries believes certain cases of food poisoning may be caused by insects, though this is impossible to confirm without data.
And if your immune system is weak, you may be more prone to contracting an illness from contaminated food brought on by insects. “Anyone who is immunocompromised will need to be exposed to less pathogen to develop an infection,” adds Devries.
Should You Throw Away Food Right Away If A Bug Lands On It?
The majority of the time, a fly’s brief landing on your food won’t make you sick.
More worrisome is when these creatures prowl around your food for extended periods of time. According to DeVries, the amount of time the bug spends on your food “probably matters, with longer exposure times leading to higher chances of people getting sick.”
“That said, I don’t know of any simple rules about when to throw out food after insect exposure,” he adds.
What should you do, therefore, if you see a fly on your food but are unsure of how long it has been there? There is no established “safe” time, thus Devries advises people to follow their instincts. Simply put: If in doubt, toss it.
How to Prevent Insects From Contacting Your Food
The likelihood of serious [health] issues is fairly low, according to DeVries, if you keep insects away from your food and preserve it correctly before and after eating.
According to the University of Sydney, here are some guidelines to keep bugs at bay and far away from your fare:
When preparing, cooking, and serving food outside, keep it covered.
Don't leave leftovers outside or on the counter unattended.
Use screens while opening windows in the house to prevent insects from entering.
To prevent pests from buzzing around your home, clean trash bins frequently, get rid of animal waste quickly (e.g., pick up dog excrement), and cover domestic rubbish.
Apply insecticidal surface sprays next to garbage cans.
So How Bad Is Eating Food That’s Had a Fly Land on It?
In the end, DeVries says, “bugs can move lots of nasty things [to your food].”
However, if you’re in generally good health, a fly that briefly lands on your dinner plate won’t usually make you sick.
But it’s best to always err on the side of caution. An insect’s likelihood of transferring potentially dangerous infections increases when it hangs out around your grub for an extended period of time. Throwing out your meals in this situation might be the best course of action. Always err on the side of caution.