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Early Bed Bug Detection Tools and Methods

By Admin, Posted October 17th 2012

When bed bugs are introduced into a dwelling, there usually aren’t more than a few of them, at first.  They may come in on your luggage when you return from a trip, or they may be in furniture or clothing purchased second hand.  They are excellent hitch hikers and can catch a ride on most anything you bring into the house.  They’ll even hide inside electronics where they go to enjoy the warmth.  As only a few will likely be introduced to the home at first, there will not be a full-fledged infestation right away.  This is the perfect time to act.

It is absolutely crucial that bed bugs be found at this stage of the infestation, before they infiltrate the entire room, or worse, the entire building.  Once that happens they’re nearly impossible to completely eradicate and it could take months, if not years of fighting against these parasites before you can safely declare the dwelling cured of infestation.  This is especially true in a home, where a nightly meal is nearly guaranteed and there are plenty of places for a small bug to hide.

If you catch them at this stage and there are only a few bugs to kill, you have a much better chance of getting rid of them quickly with contact insecticides.  If they’re allowed to mate, however, you’re soon going to have an out of control infestation.

Female bed bugs can have several sets of eggs per year, and can lay up to 500 eggs, or nymphs, in her lifetime.  Once a nymph is laid, it will grow and molt several times before reaching adulthood.  It is capable of producing up to three sets of eggs in its first year, and each of her female offspring will be capable of producing their own three sets of eggs in their first year.  You can imagine what kind of an infestation you’d have if the bugs went unnoticed for any length of time.  Once you’ve reached this point, you’re in trouble and only a lot of hard work, time, and multiple treatments will help.  It is recommended that you regularly monitor for bed bugs in order to catch any infestation in its infancy.  The presence of these bugs is exploding across the world, and it’s best to be prepared in case some come home with someone in your household.

There are ways to detect whether bed bugs are present.  Naturally, some are more reliable than others.

Visual Inspection

The cheapest method is visual inspection.  This is the least reliable because bugs scatter when they notice that you’re coming toward them.  It’s only when you’re quietly resting that they re-emerge.  You have to carefully inspect every inch of your bed, mattress, and anything around your bed for evidence of bed bugs.

To inspect an area you suspect may have bed bugs, you should have a good flashlight and magnifying glass.  The bed is the most likely place to find evidence of bed bugs because they feed on resting humans, drinking blood for meals.  They tend to stay pretty close to their feeding area, usually within a few feet, but can be found up to ten feet away.  If you have any clutter at all, especially under the bed storage, it should all be cleaned and cleared out because that’s where bed bugs will go to nest.  Once they’ve infested an area of clutter, it will be very difficult to detect and remove them.

Bed bugs tend to hide in cracks, crevices, creases, and especially along mattress seams.  Every inch of the mattress and bed should be inspected with a magnifying glass and flashlight, looking for any evidence of brown spots, red spots, shed carapaces, or nymphs.  Other furniture in the room should also be examined, as well as baseboards, window sills and treatments, wall hangings, knick knacks, and anything else present in the room.  Clothing, too, can be attractive to bed bugs, especially clothing warmth from wear.

The brown spots are fecal waste dropped by the bed bugs, the red spots are blood, taken from their human host.  Bed bugs shed their carapaces several times before adult hood, getting darker brown each time.  You may be able to find evidence of this shedding in the form of light brown, bug shaped or broken pieces of carapace.  Nymphs, or bed bug eggs, are clear and harder yet to see, but can be found anywhere because bed bugs do not necessarily nest to drop eggs.  Instead, they simply drop them as they wander around.

Even after a thorough inspection, if the infestation is new there  simply may not yet be enough evidence left behind for you to be successful detecting the presence of the bugs.  There are other methods that are more reliable.


Mattress, box spring and pillow encasements are more reliable and aside from visual inspection, the oldest known method for finding bed bugs.  Encasements must be of good quality or you’re simply throwing away money.  They should be certified bed bug proof.  The encasements must have tight teeth on the zippers and a bed bug proof closure at the end of the zipper.  They must be thick enough to keep a bed bug from biting through them.

With encasements on the mattress and pillows, bed bugs don’t have many places to hide and can more easily be found because they’re forced out into the open.  They have the added benefit of encasing any existing bed bugs inside the mattress cover, keeping them from getting out and getting to the person sleeping in the bed.  By containing the existing bed bugs inside, they can be treated and the mattress can be saved.  No more bed bugs should be able to find their way into the encasement, and fewer are able to get their meal.

Bed Bug Sniffing Dogs

There are centers around the country from which pest control companies can purchase a dog that’s been trained to detect the scent of bed bugs.  The buyer then goes to the center and trains with the dog to learn how to handle the dog during an inspection.

As a true bug, bed bugs give off a strong odor.  Dogs are able to detect that odor.  They are trained to alert the handler when the odor is present and, in theory, can find a small number of bed bugs where ever they may be hiding.

If a pest control company is well run and has a highly trained and efficient dog and a well trained handler, bed bug detection dogs can pinpoint infestations in a short period of time.  They can show the handler where larger infestations are so they can concentrate their efforts.  They can be a very useful detection tool.

There is trouble in the industry, however.  Poor training and poor handling are a big issue, and not all areas have agencies that have bed bug detection dogs.

If a dog isn’t trained well, and/or a handler isn’t working well with the dog, the dog may not alert at all for the presence of bed bugs.  It’s also possible that his handler may misinterpret an alert.  Conversely, a poorly trained dog may alert when there are no bed bugs present at all.  Both situations can be costly for the home that either has bed bugs and doesn’t find out in time, or doesn’t have bed bugs and has to spend money on treatments they don’t need.

No bed bug detection service or item is fool proof.  Sometimes the bugs just hide too well and nothing detects their hiding spots.  But there are highly effective in most situations and will find bugs if they are present.

Passive Interception Devices

Interceptor Traps

Bed bug traps are really useful devices that catch and hold bed bugs as they try to climb up the legs of a bed.  As long as covers aren’t allowed to drag on the floor, the legs of the bed are the only avenue for bugs to travel to get to their human meal.  These traps are cup shaped devices that are placed under the foot of the bed.

Some are covered in talc and the inside parts are too slippery for the bugs to climb, though the outside is textured so they can climb into the device.  The talc is there so you can see from which direction the bugs have come by examining their tracks through the talc.  It also keeps them from climbing up the bed.  They are simple, eco-friendly devices that are surprisingly effective, especially if used after treatment to see what bugs might remain.

These traps do not include any type of a lure, so they are considered passive monitoring devices.  The lure is provided by the person sleeping in the bed.  Their heat and C02 exhalations attract the bugs.

When using these the bed must be pulled away from the wall and anything else the bugs can climb, leaving the legs as their only avenue to get to their goal.  Remember to keep all bedding from hanging off the edge of the bed and touching the floor.  Remove dust ruffles.

There are also glue traps that work as passive monitoring devices.  These can be simple, flat products that are placed under the leg of the bed, surrounding the leg with about an inch of glue.  The glue is covered so you don’t have a mess when you place it.  Just rip the paper off the glue and when you sleep and your body attracts the bed bugs, they get trapped on the glue and can’t get to you.  In the morning, you can see the bugs and know from which direction they came, which helps to locate the places they are nesting.

Active Monitoring Devices

There are monitors that detect the presence of bed bugs through the  use of a lure such as carbon dioxide (C02), though some use heat and some use chemical lures.  These are commercially available and can be purchased for use by pest control services or for use by individuals.

Another type of active monitoring device is a glue trap.  They come in different styles but a popular one is a small but sturdy plastic disk on which a chemical attractant and glue is applied.  They are placed around the room suspected of having a bed bug infestation and the chemical lures the bugs to the device where they will become trapped on the glue strip.  It’s simple and easy, but perhaps not as effective as some of the other devices we’ve discussed.

Dry Ice Trap

There is a surprisingly effective do-it-yourself solution developed by Rutgers University for the purpose of monitoring for bed bugs.  In fact, it may be the most effective trap available.

The attractant is dry ice, an easily obtainable product.  This is not usually available by pest control services because the use of dry ice in homes can create liability issues.

To create this trap you’ll need a dog bowl that’s shaped similar to a trap device placed under the legs of furniture.  It is the most commonly shaped dog dish available.  You’ll also need dry ice and a Thermos in which to keep it, talcum powder, tape or sandpaper and a towel.  An easy search online for “Bed Bug Dry Ice Trap” will provide you with video instructions for making and using the trap.

Remember, though, that even if there are no bugs in the trap after use, it doesn’t necessarily mean there aren’t any bugs present.  Traps are very good indicators, but they aren’t fool proof.

Other Detection Systems

There are several other systems you can purchase or make to detect bed bugs.

Bed Bug Fecal Spot Detection Kits

These kits are generally used by commercial services, but they can be purchased for home use.  A cotton swab is used to swipe fecal spots from furniture or other places in which a bed bug nest is suspected.  The cotton swap is then swiped against a tape and treated with a detection solution.  If the smear turns blue, the spots are fecal spots from bed bugs.  This is useful only if the spots have not been cleaned with chemicals beforehand.

All of these devices and methods can successfully detect the presence of bed bugs, but none can guarantee that if they do not detect them, they are not there.  It is important to remember that none of these is infallible.


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