7 Common Household Pests to Watch

Identifying common household pests and their habits, like where they hide, can help prevent infestations or spot them early. Watch for squeaking at night, droppings, and nests made of pillow stuffing or shredded paper.

Cluster flies head indoors in autumn to outlast winter, usually gathering within crevices around windows, door frames, electrical fixtures and vents, and the areas behind exterior siding.

1. Rodents

Rodents are one of the most common household pests and cause significant problems for people. According to the National Pest Management Association (NPMA), rodents invade homes mainly during the fall and winter in search of food and shelter. They can contaminate food, damage buildings by chewing on wiring and insulation, and cause unsanitary conditions and foul odors. They also carry and transmit diseases, including rat-bite fever, plague, murine typhus, scrub typhus, trichinosis, salmonella, leptospirosis and hantavirus.

Rodents come in many shapes and sizes from the smallest mice to the pig-sized capybara and are found throughout the world in a variety of habitats. They are opportunistic feeders that consume both plant and animal matter. Many species are important in ecosystems as prey for larger predators and help spread seeds and spores.

In urban areas, rodents such as rats and mice are common in alleyways, sewers, basements and attics. In natural areas, they inhabit forests and woodlands, where they nest in trees or burrow in the ground. They are also present in grasslands where they live in large colonies and dig extensive tunnels for protection and to forage. Some rodents are solitary, while others like squirrels, chipmunks and beavers are highly social.

2. Bed Bugs

Bed bugs are wingless insects from the Cimex genus that feed on blood, usually people’s, at night. They can cause skin rashes, psychological impacts and allergic symptoms in humans. These nocturnal creatures can also spread from dwelling to dwelling by being transported on clothing, backpacks or bags. Caregivers, firefighters and other emergency service workers are especially at risk of transporting these pests. Adults are reddish-brown, flat and about the size of an apple seed. Younger bedbugs, called nymphs, are translucent or yellowish in color.

These insects pierce the skin with mouth parts that saw through the upper layers of the epidermis to access blood. The bites leave itchy, raised bumps that can lead to secondary infections like dermatitis. Some people are highly allergic to bed bug bites and develop a persistent, itchy rash.

The only species of bed bug known to occur in Indiana is Cimex lectularius, also called mahogany flat, redcoat, wall louse or mahogany louse. It is found around the world, including the continental United States, where it has numerous common names. Unlike other insects, the last larval stage of this pest transforms directly into an adult, without going through a non-feeding pupal period. Infestations are typically marked by dark spotting and staining, tan-colored skins shed by developing nymphs and rusty or reddish stains from digested blood.

3. Spiders

Spiders are a common household pest, crawling into two out of three American homes. They’re often feared and hated, but if you look beyond the scary webs that spin them and the creepy legs that skitter across the floor, you may be surprised to learn that they’re important for controlling pest populations.

Spider’s diets are diverse, and many species hunt a wide range of insects that can spread diseases to humans, including mosquitoes, fleas, flies, and cockroaches. The jumping spider (Salticidae) is one of the most effective spiders for this purpose, relying on its ability to jump several times its body length to catch a variety of insects in mid-air.

Even wolf spiders, which can be quite large—up to an inch and a half long—have a beneficial role in our ecosystems by keeping the population of other insect pests in check. These “silent sentinels” hunt ground-dwelling insects such as ants, beetles, and other spiders, and can also be helpful in keeping aphid infestations in check.

They’re also known to prey on black widows and brown recluses, helping to curb their populations. And while most spiders do not attack humans, they are “good neighbors” by reducing the number of other insects that can spread disease to people and pets.

4. Mosquitoes

Mosquitoes (Culicidae) are a significant public health concern because some species cause disease. The most significant problems are associated with mosquitoes that transmit diseases such as yellow fever, Zika virus, dengue, malaria, and filariasis. Female mosquitoes feed on blood from vertebrate hosts, including humans, to produce eggs. The saliva of some mosquitoes contains enzymes that inhibit blood clotting and help the mosquito extract blood to feed on.

Mosquito season peaks in summer, but these pests are active year-round. They can infiltrate homes through holes in walls and foundations, as well as through open windows and doors. They are especially problematic in humid climates.

Mosquito eggs hatch into aquatic larvae called wrigglers that move with jerking movements and feed on algae and organic debris. Larvae change into pupal cases that cling to surfaces. Adult mosquitoes emerge from the pupal case when water conditions change. They have two piercing mouthparts that stab into the skin to draw blood. They can be attracted to the odors of food and drink, human exhaled carbon dioxide, body odors, and movement. A hum generated by the beating of the female’s wings may aid in locating hosts. Mosquitoes can also feed on nectar and plant sugars.

5. Flies

Flies (Musca domestica) are found worldwide and contaminate food and other surfaces with microbes that can cause disease in humans, pets and livestock. Their presence in homes, barns and other structures is undesirable. Flies can also spread pathogens to animals they touch, and some species are aggressive biters.

House flies breed in organic materials such as animal carcasses, manure and garbage. They can enter homes and other buildings from open or poorly screened windows and doors, and from unclean conditions such as spilled soda or alcohol, pet feces, and scums around drains.

Cluster flies are similar to house flies but they hold their wings parallel with the body, and have no black stripes on the thorax (middle part of the fly). They invade homes in late fall or winter as they seek a warm, dry place to overwinter. They can be controlled by locating and eliminating their breeding sites in wall voids, attics, and crawl spaces.

Chattanooga pest control advices people to regularly check stored foods, spices, and dried pet foods for infestations by these pests. Store these items in airtight containers or in the refrigerator.

6. Centipedes

Centipedes, often called “hundred-leggers,” are important household pests that prey on a variety of insects and other invertebrates. Although some people think of them as frightening, these pests don’t bite and don’t cause any serious harm to humans.

During the day, house centipedes hide under objects or in damp areas and come out at night to hunt for food. They enter homes primarily through basements, crawl spaces and other damp areas but can also invade through windows, doors and cracks.

These pests can be found all over the country and are typically more of a nuisance than a health concern. They can be distinguished by their elongated, wormlike bodies and slender antennae. They have one pair of legs for each body segment and are a brown or reddish orange color.

To reduce a problem with these pests, minimize moisture and remove dark hiding places. Outside, remove leaf mulch, boards, heavy accumulations of soil and other debris that may attract them. Decrease the humidity around the home by using a dehumidifier, sealing entry points and grading the soil to drain away from foundation walls. Insecticides labeled for centipede control, such as boric acid in dust form, can be applied to crevices and other hiding places.

7. Earwigs

Earwigs get a bad rap because of their intimidating appearance, but they only pinch humans or pets in very isolated cases and cause no serious injury. They do not carry disease-causing pathogens and are not venomous, although their pincers can break skin or leave tiny red marks if handled roughly.

Nocturnal, earwigs hide during the day under loose clumps of soil, among plants or in crevices. They feed on soft-bodied pests, insect eggs and decaying plant parts and thrive in gardens, flower beds and vegetable plots. Earwigs can also be a problem in the home, seeking shelter in dark, moist crevices and moving into homes in search of food and water.

They are most problematic indoors in basements, closets and bathrooms, where they can be swept up or killed with fly swatters. To help keep them outside, remove their favorite outdoor hiding places such as piles of leaves or hay, woodpiles, thick growths of vines or weeds and dense mulch near vegetable garden beds. Eliminate moisture conditions that encourage earwigs by cleaning up rain gutters, draining puddles and reducing soil humidity. Also, seal cracks around faucets and air-conditioning units and enclose garden areas with gravel or other barriers.