Don’t let “fly” be the buzzword around your restaurant.

One of the most common restaurant pests, flies might be tiny in size, but they have the potential to leave a huge impact. From drain flies to house flies or phorid flies—these pests have no trouble slipping into your restaurant. And because of their ability to transport filth, they can pose a serious threat to your business.

No pest fulfills the adage “you are what you eat” more than flies. These insects feed on some of the grimiest substances on earth, including garbage and sewage. When flies land to feed on these substances, they can pick up billions of harmful microorganisms, including E. coli and Salmonella, which can lead to serious illnesses in humans. To transfer these microorganisms to a patron’s meal, a fly simply lands on the food and inadvertently drops off disease-causing pathogens.

There are numerous families of flies, but the two most common groups of flies impacting food handling are large flies and small flies. More specifically, the flies most commonly found in food handling establishments include the house fly, blow fly, fruit fly, drain (or moth) fly and phorid fly. Each group has its own feeding habits and preferred environments, presenting a slightly different challenge.

House Flies

These pests inhabit just about every corner of the globe aside from areas where humans are scarce. House flies carry and spread more than 100 disease-causing pathogens, such as bacteria, fungi and viruses.

House flies don’t have chewing mouthparts and thus are on a strictly soft diet of foods they can suck up through their mouthparts. They feed on everything from human food to garbage, and excrement. Because house flies are on a liquid diet, what they eat moves quickly through their system. That means they defecate almost every time they land.

Blow Flies

These flies can transfer infections to humans by contaminating food and food preparation surfaces. When the insects feed, pathogens can attach to their bodies, enabling them to spread dysentery, eye infections and other illnesses.

Blow flies typically feed on carrion (dead animals!) or dung so they are typically breeding outdoors. These pests get into restaurants through open doors, windows or vents in walls in search of food.

Fruit Flies

True to their name, fruit flies flock to overripe or decaying fruits and vegetables. This attraction to moist organic matter means you may find them circling drains, garbage disposals, trash receptacles and empty bottles, particularly beer and liquor bottles.

Fruit flies breed in moist areas that support accumulation of organic matter where “slime” of organic debris collects. Worse yet, fruit flies have tremendous reproductive potential. A female may lay up to 400 eggs in her lifetime, depositing them in decaying organic matter or fermenting fruit. Also, under ideal conditions they can develop from egg to adult in as little as seven days!

Drain Flies

Drain flies are very weak flyers, so they prefer to crawl along damp surfaces such as drains. They have a fuzzy, scale covered wings, which makes them look a bit like a tiny moth. Like the name suggests, they develop in the organic buildup of uncleaned drains. They can also be found in other areas with moist, organic buildup like loose tiles, broken underground pipes, and under grout.

Phorid Flies

Phorid flies feed on moist organic material that gathers in drains, decomposing food material often found on the floor and under equipment in kitchens and decomposing vegetables.

These flies often breed and develop deep within plumbing, which makes them hard to treat in a restaurant. Not only will they potentially infect food and food surfaces with disease-inducing microorganisms, but resolving a phorid fly problem may require expensive repairs if they develop from a plumbing leak that is underground.

Prevention Tips

In a survey of diners, Orkin found that 81 percent of patrons would never return to a restaurant if they see a pest on their plate of food. And consumers who see a pest are likely to report it—more than half say they wrote a negative online review or social media post about it.

So, how do you keep these pests from affecting your reputation? Implement an Integrated Pest Management (IPM) plan, which is a proactive approach to pest control customized to your individual business. IPM is an ongoing cycle, and it emphasizes the partnership between your pest management provider and your team. Restaurant staff should focus their efforts on proactive sanitation and maintenance of the restaurant, and they should know the correct protocol to contact a pest management professional should they spot a pest.

Here are tips your staff can use to help protect your restaurant and hard-earned reputation.

Keep the back-of-house clean. The kitchen provides ample opportunity for flies to make themselves at home, so keeping it as spotless as possible should be a priority. Ensure your staff thoroughly cleans equipment (especially underneath!) and removes all dirty dishes from the sink prior to closing each night. All standing water and spills should be mopped up immediately, and once complete, the mops and cleaning equipment should be stored in racks off the ground. In addition to spills, have your staff keep an out for leaky sinks, ice machines or soda dispensers. Kitchen drains are a hot spot for flies so be sure to monitor for liquid build-up in those areas.

Enforce stringent waste management practices. Line all trash cans, secure the lids tightly and empty the trash regularly throughout the day. When taking out the trash, take it all the way to the dumpster, as leaving trash directly outside of your building is an open invitation for flies. Dumpsters should be located as far from the restaurant as possible to keep pests at bay. You should even clean your dumpsters regularly by using an odor neutralizer to help minimize pest attraction. Don’t forget to clean your trash bins too; liners can leak and material can build up inside.

Keep your outdoor dining area tidy. If your restaurant has a patio, this should be cleaned daily by wiping up spills immediately, disinfecting tables and chairs and sweeping. Ensure all outside drains are clear of debris as pests will be attracted to the remains left behind. If your outdoor dining area is elevated, don’t forget to inspect and clean the area underneath where food particles or trash can collect. Using sodium vapor lighting at building entrances can help deter pests from doorways and prevent them from sneaking into your establishment. 

Inspect incoming food shipments. Carefully inspect for fly larvae on incoming shipments as they are off-loaded from trucks. Generally, fly eggs are too small to notice, so any adult fly activity should be noted if spotted on incoming materials.

Inspect exterior of building. Inspections help you identify the source of the problem. If problem flies appear to be entering from outside the building, inspect for breeding and feeding sites, like garbage collection areas.

Keep doors and window sealed. Ensure that doors and windows are tight against the frames and use screens to block pests from finding openings.

Report pest sightings. Guests have zero tolerance for visible pests in any restaurant establishment. Express to your employees the urgency of reporting pests immediately to remediate a problem before it becomes a bigger issue affecting your bottom line. Also, make sure you have a clear action plan that employees can follow to document any signs of pest activity.

IPM requires you to stay diligent, but a strong program will help you protect patrons from filthy, disease-causing flies and protect your business from detrimental online reviews. Don’t let flies take a bite out of your bottom line.