Posted by USBedBugs.com on 2/17/2011
Bed bug monitors can be classified as either “active” or “passive.” A passive monitor targets the behavioral patterns of bed bugs and relies on getting in their pathway or providing a need such as a cozy place to hide coupled with a mechanism such as glue or a base to either trap the bugs or show their fecal matter. The term monitor and trap are often used interchangeably because while many traps will indeed catch bed bugs, they are not designed to manage infestations alone. Rather, they are designed primarily to confirm the presence of bed bugs at all stages.
Active monitors which include the Bedbug Beacon
and the BB Alert Active
use an additional lure or “bait” such as heat, carbon dioxide, or chemicals all of which attract bed bugs to the device where they are usually trapped in glue or within a mechanism they cannot escape. The Bedbug Beacon relies on carbon dioxide (CO2) whereas the BB Alert Active uses heat. Research has demonstrated that chemical lures attract more bed bugs than control, but not at a statistically significant level.
According to the Environmental Protection Agency (EPA),
“monitors are without a doubt a valuable addition to the options available for bed bug control. Monitors using carbon dioxide, heat, and a chemical lure have great potential.” The only peer reviewed study by (Wang et al., 2009), demonstrated that monitors were more effective than visual inspection at detecting bed bug infestations and helping to estimate the number of bed bugs. There remains debate about whether heat or carbon dioxide is more effective, but researchers do know that heat is highly attractive up to about 110 degrees Fahrenheit after which it becomes a repellant. Carbon dioxide is innocuous and mimics human expiration. Monitors help save time and money by confirming the presence of bed bugs prior to consulting with a professional or having one make multiple visits.
The optimal use of active bed bug monitors will take place in a vacant room so that the bed bugs are not distracted by humans which are the core motivators of most bed bug behavior aside from mating. The presence of humans in a room being monitored will introduce at least two variables. One, the bed bugs will be more interested in the human when they are at rest than the monitor, and two, they hide from active humans. This can lead to inaccurate results. If for any reason the room cannot be left unoccupied, than both active and passive monitors should be used in combination. This practice is still however less effective than using an active monitor in an unoccupied room. One of the best times to use active bed bug monitors is “after treatment” as an ongoing effort to monitor for their presence. Optimally, active monitors will be placed in a vacant room for at least ten days or more post treatment to ensure success. Many experts recommend they be used for a minimum of two weeks post treatment, as eggs usually survive pesticide use and bed bugs are excellent hiders due to their size and shape. Bed bug monitors can detect if indeed eggs hatch after treatment and pesticide residues are insufficient to eliminate yet another infestation.
As of yet there are no head to head studies comparing monitors to canine scent detection which can be extremely accurate in well run programs. However, there is no way of knowing from team to team (a canine and its’ handler is a team) how effective they are and should therefore be used in conjunction with monitors. Monitors remain the most cost effective and reliable way to detect bed bugs even if canine scent detection is faster and proves to be as accurate as reported across the entire population as it is when tested among the very best canines.