Flies are among the most common types of household pests. Unlike most insects, which “go dormant” during the cooler months of the year, some types of houseflies actually remain active all year, coming out during warm spells in colder seasons, to once more be nuisances and lay eggs.
While they do perform important roles in promoting decomposition and even in pollinating some types of plants, sometimes they come in droves, find their way indoors, and both a pest problem and a serious health threat. At that point, it can be difficult to get rid of flies in any permanent fashion.
Flies Are a Menace
Flies not only invade yards and gardens, but also come in regular contact with people, pets and frequently-touched surfaces like countertops and tables.
A female fly can lay about 100 eggs each time she breeds. Most females breed up to five times, with a total of 500 offspring. These offspring hatch first into larvae (usually called maggots), and then mature into adult flies which then breed again, repeating the cycle.
Flies Spread Disease
As if their mere presence wasn’t enough of a reason to get rid of flies in your home, these insects also spread disease, primarily by vomiting on food and leaving droppings. The World Health Organization (WHO) notes that they are carriers of all sorts of pathogens, including those affecting the gastrointestinal tract, skin, eyes, and other organs. Flies spread disease in two ways:
- Flies like garbage, flesh, excrement, and perspiration. When they crawl around these substances looking for food, they can pick up germs on their bodies and on the little hairs that cover much of their body’s surface area. When they land on another surface, they carry those pathogens along with them, contaminating those objects (including food items and your own skin) along the way.
- Because their feeding habits put them in contact with a dizzying array of harmful germs, an adult fly can pick up a lot of bacteria and other harmful pathogens while eating. These germs can stay alive inside the fly for several days, which means flies can transmit diseases long after they’ve feasted on the initial source.
Flies can spread a wealth of diseases, including:
- Cutaneous diphtheria
- Skin infections
- Eye infections, including conjunctivitis and trachoma
Flies also carry many types of bacteria that can cause intestinal symptoms like diarrhea, upset stomach, and nausea.
Learning to differentiate from among the more common types of fly species can help you as you get rid of flies by allowing you to choose the appropriate trap or insecticide. Although most of us will only come into direct contact with a few common types in our homes and gardens, about 125,000 fly species have been identified, and there are thousands of others that have yet to be described. The six flies most commonly seen in homes and yards include:
- House fly: House flies have gray or sometimes black bodies with long lines extending down the back. Their bodies are covered with fine bristles. Some flies have yellow coloring on the sides. Little house flies are similar to “regular” house flies except for being smaller, as their name implies. They depend on animal waste and decaying garbage for food.
- Blow fly: (a.k.a., Greenbottle, Bluebottle, Cluster Fly, and Carrion Fly): Blow flies usually have a shiny, metallic-colored thorax that can be black, green or blue. Like house flies, blow flies like to breed in animal waste and decaying garbage—except for the Cluster Fly, which nevertheless breeds in indoor spaces and can be a nuisance in the late summer.
- Horse fly: This type of fly tends to stay outside, where it feeds on organic matter. But once they’re mature, female horse flies bite humans—and this is the surest way to identify these large, fast moving insects. Though they’re unlikely to invade your home, their bites can spread diseases, so it’s important to control or repel them if possible. Horse flies should not be confused with horn flies or stable flies, two biting pests prevalent among livestock. Though these present a serious threat to cattle, they do not bite humans.
- Drain fly: (a.k.a., Moth Flies): Drain flies tend to hang out around tub or sink drains. These flies are quite small (about 2 mm) and usually grayish in color. Their triangular bodies and wings create the appearance of a tiny moth—hence the name “moth fly.” Another type of drain fly, the humpbacked fly, or phorid fly, is slightly larger and has a humped appearance when viewed from the side.
- Fruit fly: The tiniest of all the flies found in homes, fruit flies are about 2 mm. in length, with brown bodies and, often, red eyes. They’re most commonly found on or hovering near overripe fruit or vegetables, and sometimes around waste pails.
- Gnats: Most gnat species are harmless, if annoying. But no-see-ums, the tiny biting curse of many summer outings, are classified as gnats, and require repellent to keep them away from their victims.
For more accurate identification, you can see pictures of common flies here.
Controlling Fly Populations: Know Where Flies Are Found
- Get rid of any standing water and make sure your gutters are effectively moving water away from your house and other areas where you hang out outdoors. Like most insects, flies like damp, moist areas, so address those areas first.
- Clean up after your pet. Animal excrement is a popular breeding site for plenty of types of flies, especially the ever-present house fly. It’s also a source of bacteria and other pathogens that can be picked up and spread by flies during and after the breeding process. So be sure to clean it up on your property, and use spray disinfectant on any accidents inside the house.
- Keep your trash cans clean and use a powerful disinfectant to get rid of residue or any matter trapped around the lid. Strong-smelling antiseptic solutions can play an important role in outdoor fly control by dissuading flies and other insects from using your cans as a breeding or resting spot.
- Clear decay. If you have fruit trees, clear away decaying fruit. Likewise for piles of decaying vegetation, especially organic debris that gets trapped in gutters or other areas around the house exterior.
- Use well-rotted manure or processed fertilizers for your garden beds. Dung and fish meal that aren’t completely or properly processed can provide a welcome haven for flies looking to breed, flies that will eventually make their way into your house.
- Keep your cesspool or pit in good working order. Usually, malfunctioning sewage lines or pits are obvious. But depending on where your pit or lines are located, you may not notice a problem right away. Keep an eye on these areas and have them maintained regularly to make them less desirable for flies.
- Take a close look indoors for places that may attract flies, including sluggish drains, overflowing or smelly garbage pails, and even perpetually-damp houseplant soil. Extra-ripe fruit can be especially attractive to flies (and not just tiny fruit flies), as can a steak or poultry left on the counter, or residues of soda, wine, vinegar, or other sugary liquids on counters and tabletops.
Getting Rid of Flies
Once you know where the flies are most likely to congregate, you can start looking for ways to get rid of flies in your home. And when it comes to fly control, you have a few options to choose from, including preventative measures, traps, bug zappers, insecticides, repellents, and other methods:
- Eliminate likely breeding spots and points of entry. Using window screens, repairing holes, and replacing ill-fitting screen frames are all good ways to keep flies from entering your home. Exit and enter quickly. If you’re cooking, avoid using your kitchen door, since flies may be hanging around waiting to get in. Seal up small crevices around other moldings, as well as air vents and openings in your soffit, all of which can enable flies to get into interior wall spaces and attics. To head off an infestation and prevent flies from overwintering in your home, do all your sealing by mid-August, a time when some flies look for warm areas to hibernate. And check for overripe fruit in bowls and other storage areas if you need to eliminate fruit flies.
- Traps: One of the most important things to know about traps is that not all flies are attracted to the same food sources. If you decide to use traps, you will likely need to use more than one to decimate your fly population. Most traps use fly bait in a special container with a cone cap that makes it easy for flies to enter but hard to escape. Pheromone traps are also available, and most can attract several types of flies. These traps use special chemical “scents” to attract flies instead of relying on food-type baits.
- “Bug zappers” can kill some types of flies attracted to light sources, and there are two types of fly-catching lights available. One uses a sticky surface or film to trap flies when they come near the light while the other type “zaps” them and kills them with electricity. This second type should not be used around food preparation or eating areas (including pet eating areas) since the zapper can spray body parts far and wide once the flies are exterminated.
- Chemicals and Insecticides: Flypaper is perhaps one of the oldest commercially-available types of house fly traps on the market. These paper traps can be laid along horizontal surfaces where flies are known to land, or it can be suspended from the ceiling to trap flies looking for a quick place to alight during flight. Spray insecticides can also be effective for indoor fly control. As with fly traps, be sure you’re using the right kind of insecticide for the flies that are causing your problem.
- Fly Repellent: Look for a personal insect repellent product designed to repel flies, and follow the instructions very closely—especially when using the repellent on young children or pets.
- More DIY Tips and Ideas: Let houseplant soil dry out between waterings to prevent dampness that can attract flies as well as other insects. Keep fruit in the fridge and spray and clean trash cans each week so odors don’t linger. Spraying your drains regularly with special foam cleaners designed to remove scum and bacterial film is one of the best ways to get rid of drain flies yourself. You can also make a spray with essential oils and distilled water or vodka, then spray areas where flies like to gather. Try pungent-smelling oils like basil, clove or citrus scents. Planting basil can also help keep flies —and other insects—at bay. If you’re dealing with a fruit fly infestation, you can make a quick and easy trap by filling an open cup with old wine: the flies mistake this for food, and get trapped by surface tension. Other homemade traps can be baited with decaying fruit, wine, fruit juice, or cider vinegar, can be effective against fruit flies. Traps for other types of flies use different kinds of fly baits. Using vinegar—plus some means of preventing flies from flying back out of the trap—will do the same for most other types of flies as well, as vinegar is often as attractive as normal food sources for a variety of fly types. Put the vinegar in a water bottle with the top cut off, turn the top over to form a funnel, and this will trap the insects inside.
Professional Pest Control for Flies
While vinegar traps, herbal sprays, and other DIY solutions can be an effective way to eliminate flies in some cases, often there comes a time when an infestation gets so severe that homemade options just don’t provide the results you’re looking for. And when it comes to flies and the diseases they can spread, you don’t want to waste time on ineffective methods. A licensed pest control expert can identify the places where flies may be gathering, breeding, or hibernating and devise a multi-pronged “attack”—using sprays, insecticides, and traps appropriate to the type of fly you’re dealing with—to keep populations under control. To get rid of house flies fast (and rid your home of other types of flies), calling a pest company can be the best option, and a top solution for preventing fly-borne diseases and health risks.