Research shows that human homes harbor an average of 100 different insect species, regardless of cleanliness or the presence of pets, which often provide outdoor bugs with free (albeit bumpy) rides to the great indoors. Glancing around my home office, I see a small spider hanging in an upper corner and a modest swarm of gnats circling my dampened snake plant. But going by those statistics, there are almost certainly dozens of other bug species in my near vicinity, hidden just out of sight (and here comes the senseless itching, oh dear God).
I like to believe that most of the insects that inhabit our homes are virtually harmless, the exceptions being the army of small cockroaches that populated my downtown apartment and ruined eating for me, and the contingent of carpet-eating moths in one of my childhood homes. But honestly, I have no idea how to tell a neutral bug from a bad bug (there are no good bugs, sorry), and I could easily be paying rent for a giant assortment of bugs that are going to make my life hell.
With this in mind, I did what any paranoid (and extremely itchy) person would do: I emailed Alec Gerry, professor of entomology at the University of California at Riverside, and asked him about the most common bugs people find in their homes, as well as how to deal with them.
Here they are, in order of how concerned you should be about them squatting in your home…
1) Termites: Of all the creepy-crawlies you might stumble upon in your home, termites are arguably the biggest cause for concern. “Termites eat wood,” explains Gerry. “Like ants, they can form very large colonies of many individuals. They live in the wooden structure of your home, or in the ground below your home, with either direct connections to wooden home supports or indirect connections to your home by building a mud tunnel from the ground to your home. Either way, termites will spend their day eating away at the wooden supports or walls that form your home.” This, he warns, “can cause thousands of dollars of damage to the structure of your home.”
Worse yet, the only real way to deal with a termite infestation is to call in the professionals. “Control will require support from a professional pest control company that may tent your house to apply insecticide, or heat to kill the termites within the house structure,” Gerry confirms. “Some termites can also be baited outside the home using insecticide-treated bait stations placed into the ground on which the termites will feed.”
2) Mosquitoes: These blood-sucking bad boys are problematic for several reasons, according to Gerry, including their “itchy bites and the potential for transmission of disease agents, like West Nile virus, that can cause illness or even death. Fortunately, very few mosquitoes actually carry or can transmit these disease agents, so the few bites that you might get inside your home are unlikely to make you sick.” Still, West Nile is no joke.
As for actually getting rid of these buggers, we first need to learn a little more about them. “Mosquitoes are aquatic during their immature life stages, where they develop in stagnant (non-flowing) water, such as that found in ornamental ponds, ditches, unmaintained (green) swimming pools or fountains, clogged rain gutters, old tires, buckets and essentially any other object that will hold water for at least a couple of weeks,” Gerry explains. “Adult mosquitoes can be daytime active or nighttime active, depending upon the species, and when active, they’ll fly toward animal hosts following host odor cues, such as the carbon dioxide that all animals exhale.”
In other words, mosquitoes need water, which is helpful information when it comes to making them go away. “Control mosquitoes by removing any potential aquatic development sites from around your home,” Gerry suggests. “Alternatively, containers can be emptied each week or treated with chlorine to control algae and microbes that the immature mosquitoes require for food. A well-maintained swimming pool, for example, will not produce mosquitoes.”
Installing some screens is another option. “When you have no control over the production site of mosquitoes, door and window screens (and keeping doors closed) will limit the number of mosquitoes that can invade your home to bite you,” says Gerry. “It has been said that indoor air conditioning and evening television are responsible for the dramatic reduction in mosquito-transmitted diseases in the U.S. since the 1950s. If you must be outside, use of CDC-approved mosquito repellents (e.g. DEET or picaridin) can provide some protection from mosquito bites.” But remember, citronella candles are unlikely to get the job done.
Installing traps, like those iridescent mosquito zappers, is also an option, albeit one that may or may not work so well. As the American Mosquito Control Association warns, “Please be cautioned against putting too much faith in traps as your sole means of control. These traps represent an evolving technology that is a most welcome addition to our mosquito control armamentarium. Their potential is great, but shouldn’t be overestimated.”
3) Fleas: Another blood-sucking insect, fleas are problematic for many of the same reasons that mosquitoes are. Gerry notes that they “can be numerous and persist for some time in the home if you have a pet that’s infested with them. Fleas that bite outside the home or enter the home from outside can potentially carry disease agents, like flea-borne typhus or plague.” Yes, freaking plague. Yikes.
Because of their attraction to pets, controlling fleas often comes down to keeping them away from your furry friends (as opposed to, y’know, your furry friends). “Fleas are common parasites of many animals, including our beloved pets,” Gerry explains. “The adult fleas can be found on animals or in the nests of animals. Immature fleas are most common in animal nesting areas, where they form into adult fleas with a pupal case, like a cocoon. They’ll emerge from this pupal case as hungry adult fleas when an animal comes near.”
“Control of fleas within the home can be achieved by applying any number of flea-control products to your pets that may have introduced the fleas,” Gerry continues. “Also, vacuuming can provide some immediate relief, as adult fleas and some immature fleas can be removed from carpets or pet bedding areas. In severe cases, or where pets aren’t the source of fleas within the home, a professional pest control company should be consulted.”
4) Cockroaches: As I learned in my downtown apartment, cockroaches freaking suck, but at least they don’t suck blood. Instead, Gerry says they “can contaminate stored foods and generally ruin one’s appetite.” He also mentions that they’re “generally considered unsanitary and will chase out your house guests.” Plus, some people can develop allergic reactions to cockroach feces and body parts.
One of the big issues with cockroaches is that they can be tough to notice before their population reaches nuclear proportions. “They’re typically nocturnally active and hide during the day, so by the time they’re noticed by the homeowner, the number of cockroaches in the home is likely to be considerable,” Gerry confirms. “Control often requires support from a professional pest control company, including the application of insecticides within the home.”
There’s also a sort of urban legend that claims stomping on cockroaches releases their eggs, resulting in more of them (and an endless stream of Kafkaesque nightmares). However, you might be happy to hear that this is a myth, and crushing a cockroach would likely also destroy any eggs it might harbor. That said, once again, killing a single cockroach will have virtually no impact on the massive colony scuttling through your walls.
5) Flies: Sure, flies might seem like a harmless nuisance, but Gerry says they have the capacity to transmit bacterial pathogens from animal feces to the food you eat. Also, these things are just really freaking annoying. “They’re attracted to food and body odors, and at night, they’ll often move to whatever room has a light on,” Gerry confirms.
Fortunately, a little cleaning up around the house should keep flies at bay. “Failure to regularly remove pet feces and poor sanitation practices related to food waste can result in the presence of many flies near (and in) your home,” Gerry explains. “Control them by improving sanitation efforts around the home and by reducing opportunities for flies to enter the home. Sanitation improvements include regular removal of pet feces from the yard (two times per week), the use of plastic trash can liners to hold food waste (be sure to tie them before disposing in outside trash cans to limit adult fly access to food waste) and regular trash pick-up from your home (don’t miss that weekly trash truck visit). The timing of municipal trash removal at weekly intervals isn’t accidental — this timing is intended to remove trash before most immature flies (i.e., maggots) in the garbage are able to complete development to the adult fly stage.”
There are also all kinds of fly traps that can be used to keep them from entering your home. “Flies are rarely produced inside the home, so they must enter from outside,” Gerry says. “They can be kept outside by limiting the time that doors are left open and by ensuring that all windows and doors left open are screened. During summer, flies can often be found resting in shaded porch areas near entrance doors and may simply follow you into the home as you open the door to enter. Hanging fly traps (the sticky kind) can be placed at this location to capture some of these flies before they enter your home. Where fly problems are persistent or contamination of food preparation areas is of concern, air curtains can be installed above doors to prevent flies from flying through doors as they’re opened. One can also simply wave your arms near the door for a moment or two before you open the door to startle the flies resting on the walls near the door so that they leave the door area before you open the door. Neighbors will enjoy the show!”
6) Bed Bugs: While these might seem like they should be higher on our list, at the very least, Gerry says, “They don’t transmit any disease agents that we know of.” On the flip side, bed bugs are making something of a comeback right now. “Bed bugs were once common in homes worldwide,” explains Gerry. “With the advent of chemical insecticides and the use of these insecticides indoors in the U.S. and most developed countries, bed bugs essentially disappeared from our homes. However, since the early 2000s, they’ve returned. Bed bugs are now a common pest in homes or residences with lots of turnover of residents (college dorms, apartments and hotels). Most hotels fortunately work hard to keep the bed bugs out.”
Much like cockroaches, their ability to hide makes them particularly hard to get rid of. “Control of bed bugs can be very challenging given their ability to hide in small cracks and crevices,” Gerry confirms. “They’ve also become resistant to some of our more common insecticides. A professional pest control company should be consulted to assist with control of this pest.”
As a quick aside, bed bugs are also super weird. “They have an interesting behavior called ‘traumatic insemination,’ which involves the male bug injecting sperm into the female bug straight through her body wall — she doesn’t have a genital opening that he can use,” Gerry explains.
7) Carpet (or Hide) Beetles: These beetles are mainly troubling because they eat all kinds of natural fibers, including those used to make many clothes. Despite their name, the chances of them eating your new carpet is surprisingly slim. “Carpets today are made with synthetic fibers that these bugs cannot eat,” Gerry says. “But that bear skin rug, deer head mount, feather boa or wool suit might suffer some damage.”
Fortunately, they’re somewhat rare in houses. “These beetles are rarely numerous in the home,” explains Gerry. “Typically, they’re discovered when opening a clothing drawer or closet storage box containing clothing made with natural animal materials (wool, hair or feathers) that’s been undisturbed for months or years.”
Unfortunately, getting rid of them might mean ditching your beloved bear skin rug. “Control is most easily achieved by eliminating clothing, rugs, blankets or other items made of natural animal materials,” says Gerry. “Where this is impractical or undesired — gotta have that bear skin rug! — then the item made with animal materials should be regularly cleaned and observed for the presence of these beetles. Beetle-infested items can be frozen or heated to high temperatures to kill the insects. For long-term storage of items made with animal materials, clean to ensure the item is free of beetles, and then place the item into a plastic container with a tight-fitting lid to prevent adult beetles from accessing it.”
8) Pantry Months: At this point, we’re really dealing with bugs that are just kind of an inconvenience. As for pantry months in particular, Gerry warns that they can result in “minor costs associated with damaged or spoiled foods — you might have to throw out your favorite cereal.”
In fact, these moths are particularly interested in that cereal. “Pantry moths lay their eggs on grains or food products made with grain flour (like cereals),” Gerry explains. “Often, an infestation of pantry moths isn’t realized until there are an unusual number of adult moths in the pantry, indicating that the homeowner is raising these moths in one or more of the food containers in the pantry — perhaps in that bag of flour that was forgotten on the top shelf.”
Of course, dealing with these buggers means dealing with your neglected pantry. “Control is achieved by a careful examination of all food boxes and food storage containers in the home, with any foods found to contain moth larvae (caterpillars) being thrown out,” says Gerry. “Technically, you can freeze the food to kill the larvae and then still use the food, but not many consumers are that cost conscious. To prevent reinfestation of the pantry, all grains and grain products should be kept in sealed containers.”
9) Ants: We’ve all seen ants storm our pantries before, and as for how concerned we should be about them, Gerry says they’re “just a bit unsightly.”
“Ants live in colonies — sometimes very large colonies, typically underground and outside the home,” Gerry continues. “However, ants forage for food all around their colony home and may even enter your home to look for food. If they find food — especially sugars or fats — they’ll leave an odor trail from the food to their colony so that other ants can follow the trail to the food. You may soon find that you have a considerable number of ants coming into your home.”
Much like other similar pests, ants can be dealt with by cleaning up. “Control them by sanitation, eliminating spilled or accessible food in the home,” Gerry says. “If an ant trail is already formed, you can identify where ants are entering your home and spray a barrier of insecticide at that location to block their entrance. Also, clean up the ant trail with soap and water (some people suggest a weak vinegar solution helps here) so that both ants and ant trail odors are removed, to keep other ants from finding and following the trail later.”
“In severe cases,” Gerry continues, “or if you just cannot seem to get control of the ants, contact a professional pest control company that can apply a barrier insecticide around your home, or can use baits to attract and kill ants outside so that they’re no longer entering your home.”
10) Spiders: Funnily enough, spiders — arguably the most feared bugs of all — are last on our list in regards to how concerned you should be about them roaming around your house. Gerry says, “They’re not much of a problem generally. But many people just find spiders to be downright scary, especially the really quick-moving ones. Black widow spiders (usually around your home, not in it) and brown widow spiders (may be in the home) are of more concern due to the toxins that they inject with a bite. But these spiders rarely bite people, so you have to be unlucky or doing something you shouldn’t be doing, like poking your finger into their web.”
While you might want to leave spiders alone, since they generally eat up the smaller, more annoying bugs roaming around your home, keeping doors and windows shut is probably the simplest way to keep them out. “Control them by having tight-fitting seals around windows and doors and eliminating holes or openings in the walls that lead to the inside of the house,” Gerry says. “Unless you have a black widow or brown recluse in your house, you may just want to capture the spider in a plastic container with a lid and put it back outside.”
So there you have it: Most of the bugs in our homes are just fine. But I’ll be adding a flamethrower to my next online shopping spree regardless.