(Step 8 of 9 in the Bed Bugs Killer Ultimate Guide - Updated March 12, 2020)
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Now it's time to assess how well all your diligence has paid off. The next step is to monitor for surviving bed bugs. If any live bed bugs survived the treatment process, the time to discover that is now. If any eggs survived and hatched a new generation, you don't want to find that out weeks from now when you're getting eaten alive every night again. Bed bug monitoring is the way to protect your progress in battling your home's invaders is to stay vigilant and monitor for any signs of survival.
This article looks at best bed bug monitoring practices after treatment. It's based on recommendations from exterminators who specialize in bed bug treatments, experts in several university entomology departments, and public health officials. Essentially, you're trying to achieve 50 to 60 days with no signs of bed bugs – no bites, no eggs, no shed skin, no dead bugs in monitors – nothing.
In some ways, monitoring takes you full circle, because you're returning to a focus on detecting bed bugs. If you have followed the treatment protocol prescribed throughout this guide, by now, any bed bug infestation you still have should be "low level." According to entomologists at the University of Minnesota, professionals describe a low-level infestation as 20 or fewer bed bugs. More than 20 and less than 100 would be a moderate infestation. Determining how many, if any, are left after treatment is the primary goal of bed bug monitoring. And ongoing monitoring is critical to early detection of bed bug survival after treatment.
Survival Rate Factors and Monitoring Tools
The survival rate at this point can depend on several factors:
Your monitoring tools will include:
Aside from trapping and encasing bed bugs already on your mattress, encasements make it easier to see bed bugs who survived and are still coming to your bed to feed. If they are outside the encasement, you still have bed bugs.
Interceptors and monitors will trap bed bugs attempting to climb up your bed if you deprive them of using any other route.
You should also continue to apply the inspection methods you used when originally attempting to detect bed bugs. Cracks and crevices may still hide survivors. However, at this point, visual inspection alone probably won't be enough. It's more difficult to detect bed bugs when you have a low-level infestation. So do use monitors to supplement your inspection.
Further, if you or other family members are still getting bitten, then you know your job is not finished.
To start, you'll want a simple bed bug monitoring device that works for you 24 hours a day.
Bed Bug Traps Provide Early and Ongoing Detection
The easiest way to monitor for bed bugs is to create an early detection system around your bed. Why? If there are still bed bugs in the house, they will find your bed. The carbon dioxide you exhale as you sleep is a telltale sign that their next meal is nearby. They will move with all deliberate speed to track you down. So, attract them but set a trap for them.
If you removed all other access, bed bugs will climb up the legs to reach you in bed. You want to create a barrier that stops them from making it all the way up to your mattress or box spring.
In the past, when having bed bugs was the norm, families commonly set up these types of barriers. They serve the dual purpose of protecting you from getting bitten and alerting you that you have bed bugs nearby.
DIY Monitoring Devices
Here's how to create your own bed bug trap:
- 1Set double bowls – a small bowl inside a larger one – under the legs of your bed.
- 2Wrap the outside of the larger bowl with tape or fabric, something to give it texture. Bed bugs can't climb up smooth surfaces.
- 3Fill the bottom of the larger bowl with soapy water.
- 4Place a talcum powder and diatomaceous earth mixture into the smaller bowl. The talcum powder will help make the inside slippery, keeping the insects from climbing out, and the DE will help dehydrate them.
- 5Lather petroleum jelly onto the legs of your bed frame as an added precaution.
You also can place rubbing alcohol instead of soapy water into the larger bowl. Either will drown or kill bed bugs.
The smaller bowl is meant to trap any bed bugs who are already on your bed and climbing down to return to their daytime hiding places. The larger bowl, containing the liquid, traps and drowns any bed bugs that are climbing up.
The talcum powder makes the sides slippery and helps keep bed bugs from climbing out. The diatomaceous earth goes to work killing them by cutting and dehydrating them after they touch it. With two bowls, whether going up or coming down, one is sure to trap them. Simple but ingenious.
For this method to work, you must deny bed bugs all other means of entry to your bed. Remember, bed bugs do not fly. They must crawl to their destinations. The bed legs have to be their only travel option as a route to and from your bed.
So, make sure you don't allow your sheets, blankets, or other bedding to touch the floor, giving them an alternate travel route. Similarly, make sure your headboard does not offer another easy access.
If you did not earlier isolate your bed and move it at least 6 inches away from all walls, curtains, nightstands, and other furniture, now is the time to do this.
Watch a Demonstration
Watch entomologist Dr. Rebecca Baldwin from the Univeristy of Virginia demonstrate the assembly of a DIY bed bug trap.
Will Monitors Stop Me from Getting Bitten?
After treatment, theoretically, yes, using bed bug monitors should stop you from getting bitten, if you have:
- 1Treated the bed and your bedroom.
- 2Encased your mattress, box springs, and pillows.
- 3Isolated your bed and kept your bedding from touching the floor.
If you have done all these things, then, theoretically, the only way more bed bugs can get to you is by climbing up the legs of your bed. The monitors will stop them.
Do Professional Bed Bug Monitors Work?
Yes, if you understand that their purpose is to monitor the area around your bed for the presence of bed bugs. They are not intended to be your treatment plan.
Professional traps started being integrated routinely into treatment plans after an early study confirmed their value. It confirmed that bed bug traps captured pests even after exterminator inspections had found no further infestations. The study determined that bed bug traps do successfully intercept bed bugs on the way to their next blood meal. Other studies found that if left in place for at least a week, bed bug interceptors can detect 70 to 80% of bed bugs in a low-level infestation. Over a two-week period, they detected up to 90% of bed bugs in the test unit.
Two Types of Professional Monitors
Passive or active? These are two different, but effective, approaches professional bed bug monitors employ.
Passive monitors, also known commonly as bed bug interceptors, are designed to wait for bed bugs to come out to feed. You and the carbon dioxide you release as you sleep are the irresistible attractant that lures bed bugs to your bed. Remember, bed bugs need to feed before they release eggs or advance to the next stage in their life cycle. Interceptors stand between you and another bed bug meal by intercepting the insects as they attempt to climb onto your bed.
Professional bed bug interceptors employ a "pitfall" design, much like the one noted in the DIY passive interceptor we described above. Essentially, the bed bug climbs up the outer cup of a two-cup monitor. Once inside, a smooth inner surface keeps the bug from being able to climb out or up and into the inner cup to access your bed leg.
Bed bugs climbing down from your mattress or box spring wind up inside the inner cup. Coating it with diatomaceous earth or CineXma ensures they become too sick to climb back up onto your bed again.
The design is sometimes referred as a "moat" style. Just as the moats of olden times encircled and created a defensive barrier to kings' castles, these moats serve to defend you. The leg of your bed (or couch or chair) sits inside the inner cup, which is surrounded by talcum powder in the outer well to keep invaders from making further progress. The ClimbUp interceptor is an example of a passive bed bug monitor. Studies by entomologist Changlu Wang at Rutgers University found this brand to be particularly effective at monitoring bed bugs.
A second type of passive bed bug monitor, sticky traps, has been found ineffective in virtually every study on effective monitors. Avoid them. They seem best at collecting dirt and pet hair.
Have an empty bedroom or a vacation home you only use a few weeks out of the year? Then, an active bed bug monitor might render the best results for you after treatment.
Active monitors are designed to proactively lure bed bugs from their hiding places to pursue their blood meal. They depend on attractants designed to emulate the heat or carbon dioxide released by a sleeping person. Some monitors use pheromones that mimic human sweat as the attractant. Studies have shown carbon dioxide and heat to be the two most effective attractants in active monitors.
Bed Bug Beacon and SenSci Volcano are two examples of active monitors. With these kinds of detectors, lures need to be replaced regularly to stay fresh.
The SenSci Volcano, designed by Rutgers University entomologists, actually, is an example of a dual-action monitor; it can be used as an active or passive monitor. However, tests suggests that it works best as an active monitor, in which a lure is employed to attract bed bugs.
Watch entomologist Jeff White describe how passive and active monitors work.
Which Type of Monitor Should I Use?
For monitoring after your first treatment, we recommend passive interceptors in rooms that are regularly occupied. Why? Two reasons: first, they are inexpensive compared to active monitors, and they require a live lure, you, to attract bed bugs from their hiding place.
In empty rooms, such as a guest room or an infrequently used vacation home, an active monitor could prove more successful. Without a live lure sleeping in the room, an artifical attractant might be needed to draw out bed bugs. Remember, without a lure, they can wait a year for a live blood meal to show up.
Another difference between the two designs is cost. A pack of four passive monitors for one bed should cost less than $20 with no need to refill anything. (Adding talcum powder or diatomaceous earth is optional.) An active monitor can cost anywhere from about $50 to hundreds of dollars, and it requires regular replacement (about every 90 days) of the lures. You simply don't need this to monitor a low-level infestation.
If you prefer to use an active monitor, you can learn how to build one yourself here.
Where Should I Place the Monitors?
In occupied rooms, place one passive interceptor under each leg of the bed (or sofa or chair).
In unoccupied rooms, you have a decision to make. If active monitors are in your budget, they will probably render results faster than passive monitors. But if no one is going to be sleeping in the room soon, you probably can afford to rely on just setting and leaving passive monitors in place for an extended period. Again, place one passive interceptor under each leg of the bed.
If you're using active monitors, set the lures around the perimeter of the room to capture bed bugs as they travel along walls to get to your bed. Set additional lures next to the legs of your bed (or sofa or chair).
How Soon Will the Monitor Work?
Generally, active monitors reveal signs of bed bugs in four days or less. Passive interceptor traps may take a week or more.
In either case, the fact that no bed bugs have been captured in a week does not mean you don't have bed bugs. Remember, your goal is 50 to 60 days with no signs of bed bugs before you can declare your home bed bug–free. So expect to leave the monitors in place for at least 60 days.
In any case, plan to treat again within 10 days of the first treatment.
What If I Get Bed Bugs in the Trap?
First, bed bugs in the trap confirm that you have more work to do. Pay attention to which monitor captured the bed bugs. Was it trying to climb up or down from your bed? If they are in the inner well, you know bed bugs are still hanging out on your bed outside the encasement covers. Don't remove the encasement covers, but do launder your bedding again.
Which wall is the interceptor closest to? Bed bugs tend not to travel farther than necessary for a meal. These are all clues about where to focus during your follow-up treatments.
To empty the trap, you have a few options. If you built your own and used soapy water, simply flush it down the toilet. If you used a talcum-powdered or dusted interceptor, empty everything into a sealed bag and throw it in the trash outside. You will need to replace the talcum powder or bed bug dust. If bed bugs are still alive, you can flush them or use contact bed bug spray to finish the job. Your choice.
What Should I Look for When Buying?
To decide what's best for your post-treatment monitoring needs, focus on these criteria:
Are you buying for an occupied or unoccupied sleeping area? For the rooms your family is sleeping in, a passive monitor is preferable for post-treatment monitoring. For a room in which no one will be sleeping for weeks or months, an active monitor will give you the quickest results (4 – 7 days). A passive monitor will still do the job, but it will probably take significantly longer because it lacks an active lure.
Budget? How many bedrooms do you need to monitor? (Also, do you need to monitor areas where you have a couch and chairs? Did you discover bed bugs there? Did you treat for bed bugs in those rooms?) Passive monitors usually come in packs of 4 or 12. Active monitors like Bed Bugs Beacon are single units. SenSci Volcano monitors come in packs of 12, but the lures are sold separately, unless you get a starter kit with 4 of each. The cost difference can be significant if you need to treat multiple rooms.
Will the monitors be sitting on a carpeted or bare floor? This matters because some brands are sturdier than others. They vary in the hardness and thickness of the plastic they use. Heavy beds or carpeted floors may break some brands. LightsOut gets higher marks, as does ClimbUp, which now uses a "no-break polypropylene." Still, it's best to set something under the monitor to keep it from cracking on carpeted floors. For hardwood floors, it's recommended that you place felt pads under the monitors to keep the bed from moving around and scratching the floor.
Leg width? Do you need a standard-sized pitfall cup or extra large? Measure the width of your bed's legs (or sofa or chair). If they are more than 3.75 inches, you will need a large passive monitor to fit the legs into the inner cup. On most pitfall models, the inner cup measures only 4 to 4.5 inches. (This won't matter for active monitors.) Not all passive monitors come in multiple sizes. An extra large bed bug interceptor size is available in the ClimbUp and EcoPest brands, with an inner cup that measures 5.5 inches.
Top Passive Monitors
ClimbUp
This is the most popular bed bug interceptor brand. In response to complaints about cracking under pressure from beds, the manufacturer introduced a new, sturdier plastic made from polypropylene. The design change also created a smoother inside outer well, eliminating the need for talcum powder to keep bed bugs from climbing out. Amazon sells ClimbUp in a 4 pack if you only need to monitor one bed or sofa. They also offer an extra large size for bed legs too large to fit the 4-inch well of the original. DoMyOwn offers a convenient 12 pack for more extensive monitoring.
LightsOut
This brand gets high marks from pest management professionals and consumers alike. Its black color is designed to take advantage of bed bug's natural attraction to black and red objects. The black color also helps eggs and nymphs, which are both light-colored, stand out. Adults are red, and will also be readily visible. LightsOut is made from a crack- and break-resistant recyable plastic. It neither needs nor uses powder to contain bed bugs that have slipped inside, so there are no cost beyond the initial purchase. Amazon sells LightsOut in a 4 pack if you only need to monitor one bed or sofa. DoMyOwn offers a convenient 12 pack for more extensive monitoring.
Here is entomologist Jeff White describing the LightsOut bed bugs interceptor, which he designed (formerly known as BlackOut).
EcoPest Labs Bed Bug Blocker Pro
These use the same dual-cup, pitfall design as ClimbUp and LightsOut. They are designed for heavy-duty use. Still, it's a good idea to set a hard surface beneath them to prevent them from cracking under the weight of a bed and its occupants. They come in the standard 4-inch inner well size and an extra large size. They do not use or need any type of powder to keep bed bugs inside. Amazon offers the EcoPest monitor in 4-, 8-, and 12-pack options. You also have a choice of black or white monitors, as well as XL. The extra large bed bugs interceptor measures 7" x 5".
Top Active Monitors
Bed Bug Beacon CO2 Monitor
For best results, place this monitor along baseboards and in corners. The BB Beacon comes with enough CO2 to monitor bed bugs for 11 days. The kit consists of a pitfall monitor attached to a bottle that feeds it CO2. Two packets of dry CO2 are included. Mix with water and fill the bottle.
The Beacon is one of the last CO2 monitors left on the market. Others, like the NightWatch, failed because they were too expensive. Still, the packets for this unit need to be replaced every two weeks, which can add up.
The video demonstrates how to set up the monitor. As you can see, it's a bit more challenging than setting the passive monitors under the legs of furniture.
The CO2 mimics the carbon dioxide released as we sleep. These units are best when placed into empty or unoccupied rooms you want to monitor after treatment.
SenSci Volcano Bed Bug Detectors with SenSciActiv Lures
The basic design of the SenSci Volcano is passive. It's the addition of attractants that makes it an active monitor. You can use it without the lures as a passive monitor, but the lures help reduce the time to confirm whether you still have bed bugs. Active lures are best for unoccupied rooms. If someone is sleeping in the room, their CO2 competes with the lures, basically making them unnecessary.
Active lures like SenSci work best when placed along walls and other pathways bed bugs are most likely to use to try and reach a bed. Placing additional units near the bed legs enhances the results.
Watch Jeff White as he describes how to get the most out of placements for the SenSci Volcano.
SenSci Volcano, sold by DoMyOwn.com, comes as a pack of 12 monitors. The lures, which are sold separately, also come as a pack of 12. However, Amazon sells a bed bug detection kit with 2 Volcanoes and 2 lures. Expect the Volcano monitors to last up to a year and the lures 2 to 3 months, enough time for post-treatment monitoring.
So, Which One?
Any one of these would serve your needs for post-treatment monitoring. Each is well-rated. It's a matter of reviewing the criteria and deciding which apply to you. If you have multiple rooms to treat, any of the 12-pack passive monitors will probably work best for you. If you treated a bed (or sofa or chairs) with larger legs, look to the XL options offered by ClimbUp and EcoPest. If you want an active lure, SenSci Volcanoes and lures probably give you the most flexibility.
We'll do an-indepth comparison and buying guide to bed bug monitors in a later article.
Whether you find bed bugs in the interceptor or not, plan to treat again in about 10 days. You should do at least two follow-ups to be sure. When you no longer see bed bugs in the trap or elsewhere and no one has been bitten for 60 days, you can assume that your bed bug problem has been solved.
Next: Prevention
Rinse and repeat the treatment process as long as needed. Once they are gone, you want to make sure it's harder for any new bed bugs to enter your home. Next, we'll take a look at how to put out the "not welcome" sign at the front door by preventing bed bugs.
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