We don’t get very many good descriptions or sustained discussion, much less diagrams, of the spread of bed bugs within buildings. Here are two discussions and, in one of the papers, a diagram, a diagram you could make a flip book out of. A flip book of bed bug misery.
First, the nursing home.
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A letter in the upcoming June issue of the CDC journal Emerging Infectious Diseases, Bedbugs and Healthcare-associated Dermatitis, France, P. Delaunay et al. (PDF), describes an interesting story of bed bugs at a nursing home:
In July 2007, Mrs. Q arrived, with her bed and mattress, for admission to a single room in a hospital nursing home. This facility has 112 rooms located on 2 floors, each having A and B wings. Mrs. Q’s first lesions, diagnosed as insect bites, appeared in October 2007. Concomitantly, Mrs. T, a long-term resident of the room across the hall (1.5 m away), developed similar lesions. Examination of Mrs. Q’s room led to the discovery of an aggregation of 200 C. lectularius bedbugs beneath her mattress.
What the authors call a “nonspecific pest-control intervention” (maybe take a guess at what that means or just think about it for a second) occurred in Mrs. Q’s and Mrs. T’s rooms plus a third room. By November two additional rooms had bed bugs. These rooms plus ten more were treated—but this time by the nursing home staff, and there’s a somewhat alarming mention of insecticides applied to clothing at this point.
Nothing for the next 4 months.
And then in March 2008 another patient on the same floor.
And then a “specialized private company” treats 56 rooms over a period of 2 months.
The authors express some thoughts on the likely mechanisms of dispersal during this particular infestation and I’m not sure that I agree with the assumptions—32 meters not sounding like a big obstacle to me. But who am I. Read for yourself. Also, I imagine the preventive application of bendiocarb will give many pause. But it looks like things worked out and the infestation was eradicated.
Good for Mrs. Q and Mrs. T and fellow patients.
The authors conclude with a small understatement:
At this time, healthcare facilities provide a welcoming environment for future bedbug-dermatitis outbreaks.
Delaunay P., Blanc V., Dandine M., Del Giudice P., Franc M., Pomares-Estran C., et al. (2009) Bedbugs and healthcare-associated dermatitis, France (PDF) Emerging Infectious Diseases [Published online ahead of print] DOI: 10.3201/eid1506.081480
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There is a very nice set of three diagrams of the spread of bed bugs in a hospital’s staff quarters over a 2-year period in Doggett and Russell’s ICUP paper: The Resurgence of Bed Bugs, Cimex spp. (Hemiptera: Cimicidae) in Australia (PDF).
Stephen Doggett and Richard Russell write:
One facility was a staff accommodation block attached to a tertiary health care facility. Between 2003 and 2005, bed bugs became a serious issue and rapidly spread throughout the building. Figures 10a, b and c, show the spread of the infestation, which was recorded via staff incidence reports. The first infestations was identified and treated (albeit poorly) in May 2003 and, by May 2005, 10% of the rooms were infested, which led to all rooms being inspected by a bed bug experienced Pest Manager. The final survey (July 2005 in Figure 10c) revealed that a total of almost 20% of the rooms had evidence of bed bugs (68 rooms infested). Costs in this instance included: replacement of bedding and linen (>A$7,220), pest control (approx. A$32,000), control equipment (>A$1,000) and intellectual support (>A$2,000). The total of around A$42,000 equates to A$617/room, although many costs were not included such as the medical expenses for treating afflicted staff, loss of productivity with such staff, and various miscellaneous costs.
I was reminded of this paper because Richard Cooper makes reference to this infestation and these diagrams in his EPA presentation, a 10 minute video of which you can download here (wmv format). So, in other words, let me encourage you again, for other EPA presentations, see this page at EPA. The ICUP papers, minus one I managed to miss, we listed here.