The bed bug, Cimex lectularius L. (Phylum Arthropoda, Class Insecta, Order Hemiptera, Family Cimicidae) has sucked the blood of humans for thousands of years (Panagiotakopulu & Buckland 1999). The tropical bed bug, Cimex hemipterus Fabr., also has a long history of sucking the blood of humans in the tropics and subtropics. To complicate matters, there is a small group of related blood sucking bugs in the family Cimicidae including bat bugs and swallow bugs that will feed on humans and can be confused with human bed bugs. All of these human blood sucking bugs have no tarsal pads and can only climb a vertical surface by using tarsal claws hooked into a rough surface (Usinger, 1966).
Bed bug adults are reddish-brown, oval, wingless, flattened insects about 6-9 mm long that are readily seen with the naked eye. Newly hatched bugs feed at the first opportunity. They molt five times before reaching maturity and require at least one blood meal between each molt. Bed bug adults often survive up to 2 months without food, but under certain circumstances can live a year or more without feeding. Bed bugs are active during the nighttime and hide during the daytime into tiny crevices or cracks. They rapidly move into a refuge when disturbed by light or air movement so they are rarely seen by the person who is bitten. Bed bugs are able to cling to possessions using tarsal claws and hide in small spaces so that they may easily be transported in a traveler's belongings (Usinger 1966).
Most U.S. householders of this generation have never seen a bed bug (Busvine 1980). In the 1940s and 1950s in U.S. and Europe, DDT sprays replaced all other methods of bed bug control resulting in a decline in bed bug infestations (Mallis 1960).
DDT was very effective but the first bed bug resistance to DDT was observed by Johnson and Hill in 1948. As time went by and different pesticides were used, bed bugs developed resistance to each in turn (Cwilich et al. 1957, Fletcher & Axtell 1993, Lofgren et al. 1958, Moore and Miller 2006). During the last decade, bed bugs have become a serious commercial health problem in resort hotels, apartments, college dormitories, and cruise ships. Less effective and shorter acting bed bug pesticides have contributed to the resurgence of human bed bugs and a world-wide pandemic is taking place (Doggett et al. 2006, Romero et al. 2007). When hungry, bed bugs actively seek and find humans using a combination of cues (Lehane 2005, Reinhardt & Siva-Jothy 2007). Carbon dioxide is an activator and attractant to bed bugs (Marx 1955). Heat is an attractant to bed bugs (Rivnay 1932, Aboul-Nasr & Erakey 1967). And, as with all blood-sucking arthropods, host-emitted odors are reliable cues for both activation behaviors and attraction behaviors (Aboul-Nasr & Erakey 1968a, Sutcliffe 1987, Murlis et al. 1992).
Prior work using human attraction cues to lure crawling blood-sucking arthropods other than bed bugs is known. Montemurro in U.S. Pat. No. 5,189,830 in 1993 discloses trap using carbon dioxide to attract ticks. Keenan in U.S. Pat. No. 5,258,176 in 1993 discloses the use of heat and volatile odors to attract fleas and ticks to trap.
A rough, vertical surface is attractive to bed bugs. To walk up a vertical surface, around a human body, or upside down under a bed, bed bugs use their hook-like tarsal claws to engage fibers and surface roughness (Usinger 1960). Hungry bed bugs tend to crawl upward on rough surfaces and bed bugs will crawl on cotton or wool (Aboul-Nasr & Erakey 1968b). Bat bugs walk up the walls of caves and will climb vertically up a rough piece of wood (Overal & Wingate 1976). In contrast, a smooth surface is repellent to bed bugs and bed bugs will avoid the smooth surface of silk (Aboul-Nasr A& Erakey 1968b). Smooth glass containers are used routinely to contain laboratory colonies of crawling insects because they cannot gain traction on smooth surfaces (Marshall 1981). By the mid 18th century, cheap metal bedsteads were known to deter bed bugs (Wright 1962).
The pitfall trap is an adaptation of hunting techniques that dates back to primitive man. The basic insect pitfall trap outdoors comprises a container (a jar, can, or other container) buried in the soil so that the top edge of the container is at the same level of soil surface or just below the soil surface. Crawling insects and spiders fall into the trap and are unable to escape because they cannot climb up the smooth interior surface. Cockroach traps with pitfall aspects have caught bed bugs (Mellanby 1939).
Smooth, hard surface of pitfall interior surface can be created from glass, ceramics, metals, finish treatments on polished wood, finish treatments on paper, and plastics. The surface roughness (Ra) of an optical grade mirror finish is 0 to 0.5 microinch (0.0127 micron), of a satin finish is 50 to 60 microinch (1.27 to 1.524 micron), and of an embossed or coarsely textured product is up to 300 microinch (7.62 micron) (Hebert 2007).
Many crawling insect traps with pitfall aspects or moats to prevent insects from reaching food have been disclosed. For example, U.S. Pat. No. 2,790,417 issued to Brembeck, U.S. Pat. No. 5,277,149 issued to East, U.S. Pat. No. 3,441,003 issued to Du Mond et al., U.S. Pat. No. 5,148,626 issued to Haake, U.S. Pat. No. 5,253,609 issued to Partelow et al., U.S. Pat. No. 5,165,365 issued to Thompson, U.S. Pat. No. 5,113,798 issued to Rera, U.S. Pat. No. 4,128,080 issued to Haney, U.S. Pat. No. 5,125,363 issued to McGaha and U.S. Pat. No. 4,399,772 issued to Salinas all employ a device that may prevent crawling insects such as ants and cockroaches from reaching a pet food dish. Sherman in U.S. Pat. No. 4,608,774 in 1986 discloses an indoor pitfall trap for cockroaches. Spragins in U.S. Pat. No. 6,860,062 in 2005 discloses an adaptation of an outdoor pitfall trap for both crawling and flying insects.
U.S. Pat. No. 4,953,506 issued to Sanders also discloses a device that may prevent crawling insects such as ants and cockroaches from reaching a food dish. However, this patented device requires the use of a sticky substance to trap the crawling insects. This patent will trap insects as long as the insects themselves cannot form a physical bridge over the sticky substance. The Lang U.S. Patent application No. 20070044372 for a bed bug monitor trap also requires the use of a sticky substance to trap and it also discloses use of heat as an attractant for bed bugs.
U.S. Pat. No. 2,167,978 issued to Jennerich, U.S. Pat. No. 1,265,481 issued to Mosby, U.S. Pat. No. 944,568 issued to Mercer. U.S. Pat. No. 52,576 issued to Lamb, U.S. Pat. No. 533,017 issued to Peeler, and U.S. Pat. No. 21,726 issued to Shell, all teach devices devoted to trapping insects.
U.S. Pat. No. 3,901,192 issued to Adams discloses a bird feeder having a cup like container for the bird seed that is protected by moat or pesticide from crawling insects. U.S. Pat. No. 5,440,833 issued to Stoll discloses a device that creates a double catchment area barrier between an item to be protected and insects that could crawl downward from an overhead surface or upward from below.
U.S. Pat. No. 5,881,671 issued to Riedl discloses apparatus that can be attached to a pet food dish or picnic table leg capable of preventing crawling insects from infesting a food source.
U.S. Pat. Nos. 6,505,433. 6,510,648 and 6,513,280 issued to Roberts discloses a coaster for shielding against crawling arthropods.
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