Observations on the spread patterns of bed bugs when the bed is preemptively isolated with climb up interceptors.

My entire apartment block is inspected for bed bugs on a yearly basis. One tenant requested climb up interceptors on a permanent basis and stated they would monitor themselves. I agreed because the tenant appeared competent and would immediately let me know if there was a problem.

Unfortunately the tenant, in his zest for cooperation, decided to add powder to the interceptors which rendered any bug that fell into the device invisible. As a result the tenant could not recognize bed bugs. I was alerted to bed bugs when bugs were observed on the couches. I would estimate the infestation to be 3 or 4 months old based on the number of bugs observed. The climb up interceptors contained about 50 bed bugs hidden under the powder. The mattress appeared bug free but the box spring had a small amount of bug evidence on the wooden slats. Bugs were also noted on the main couch with live bugs under the plastic legs and, interestingly enough, on the throw pillows that were resting on top of the couch back rest. Usually in smaller infestations (there were about 5 live bugs observed on this couch) these pillows do not have bed bugs. A secondary couch also had one live bug observed and an easy chair also had 3 live bugs observed.

Interestingly enough the tenant noted 2 live bugs climbing the walls in the hallway and one bug in the bathroom. The two bugs on the hallway walls had me a bit puzzled and I suspected the tenant had sprayed RAID. The tenant stated he had not sprayed anything but did vacuum the couch.

All couches, beds, and easy chair were heat sterilized in my trailer. I tore the rest of the suite apart looking for bugs and found no evidence. As such the evidence suggests the tenant did not spray RAID despite the two bugs on the wall. Perhaps a vacuuming disturbed their harbourage and caused them to flee? Very unusual.

The most disturbing aspect to this suite was that the bugs were feeding on three separate pieces of furniture in the living room despite the fact the infestation was not that big, and that the tenants did not sleep there. Normally in small infestations all (or most) the bugs are on the bed. The danger is that the bugs will then transfer elsewhere as the tenant goes about daily life. I suspect the bugs transferred to the bed in this manner as the interceptors prevented infesting the bed in the usual way.

I learned that if you prevent bugs from feeding on the bed with interceptors, a certain percentage of the bugs will be caught in the interceptors but the remainder will feed on the tenant during the day in the living room. This coincides with another report I received from a landlord customer who attempted to use interceptors without chemical treatments and found the bugs were chasing the tenant during the day. Day time feeding has great potential for harm.


Update: February 20, 2014

When the suite was treated  for bed bugs earlier the bed, couches, and the easy chair were isolated with modified glue board traps.  At the two week mark the suite was inspected and retreated.  The glue boards contained 16 bed bugs roughly evenly split between the bedroom and the livingroom.   The bugs off the bed in the bedroom had been unable to feed and therefore unable to make harbourages in the bedroom (during treatment there were no hartbourages observed in any bedroom furniture).   Despite this limitation half the bugs were still caught in the bedroom during the two week span between treatment and inspection.   Amazing.  The bugs in the livingroom appeared to be divided between accessing a more dangerous day time meal in the living room and a safer night time meal in the bedroom.


The suite across the hall remained unaffected.  That means the bugs walked right past the suite door  and found the bedroom without getting lost.  How they did that I do not know.  The distance from the couch to the bed is approximately 20 feet – well beyond their ability to sense Co2.


Update February 25, 2014


Treated entire suite again today.  The glue board bed/couch leg traps contained 3 bugs – two in the livingroom and one in the bedroom.  It is moving in the right direction.  Interestingly all the bugs caught were second and third instars.  Normally in a baiting situation like this the older bugs are the last hold outs.  In this case it is the younger ones.   I also noted that the interceptors when they were first checked contained a fair number of adult  bed bugs.  So far in this treatment I have seen very few adults – mostly 3rd instar or less.   This suite certainly has some odd bed bug presentations.


Update March 11, 2014


treated entire suite again today.  zero bugs were trapped in the bedroom where the tenant slept and three bugs were caught on the couch glue board traps under the couch in the livingroom (two first instars and a skinny second instar).  Again only immature bugs and this time only in the livingroom.  The bedroom was bug free!!  I asked the tenants about potential reinfestation from work lockers but the tenants became defensive and I could get no good information from them.  That is unfortunate as this case is an excellent learning experience.  I am suspecting that the isolation of the bed by definition pushed  more bugs into  day time feeding which leads to more infestations outside the home.  Those infestations then come home to roost later making successful treatment in this suite problematic.  We will see.


update March 24, 2014

zero bugs today in the inspection.  I will note, however, that 4 treatments is a bit unusual to get results especially when only 16 bugs were caught in the traps the first time.  In other cases with 30 plus bugs caught in the traps only two, or sometimes three, treatments were required.  In my non chemical experiment, detailed in my DEET spraying in multi family post, it took only one month to bait and trap the bugs and 30 plus bugs were caught in that instance. This was a smaller infestation that took twice as long to treat.

update April 5, 2014

suite inspected again and no activity was  noted in the glue board/interceptor traps except for one large adult in the middle of the glue board.  Normally the bugs are caught on the very edge so that was unusual.  A careful examination with magnification revealed that the bugs had no legs except for half of one front leg.  An additional part leg was discovered in the glue board nearby.  The rest of the legs were nowhere to be found.  I concluded that this bug had been heated earlier (with the first heat sterilization) and had now fallen off the furniture into the glue board.  Heated bugs become brittle and fall apart just like this bug appears to be.  The issue of false positives in glue boards is actually a  relatively common issue that I have noted on other occasions as well.  If we get zero bugs in the next inspection in two weeks I will declare this suite bug free.


update April 21, 2014

all 19 modified glueboard traps under beds, couches, and easy chair were inspected and found to be  bug free.  I allowed the tenant to put their clothing back into normal positions and resume normal life.  I will, however, continue monitoring


Update May 29, 2014

Inspected all modified glue board traps and found zero evidence of bed bugs.  That would make approximately 3  months of zero.   I declared the suite bug free and removed all the traps.     All neighbouring suites are also bug free.   I will inspect again during the next building wide  bed bug check.

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