Bed bug control techniques

Cimicidae or bed bugs (sometimes bedbugs), are small parasitic insects.The term usually refers to species that prefer to feed on human blood.

Early detection and treatment are therefore critical in success of control. According to a survey, the most commonly infested places are the mattress (98.2%), boxspring (93.6%), as well as nearby carpets and baseboards (94.1%).^[1] In fact, bed bugs thrive in areas where there is an adequate supply of available hosts, and plenty of cracks and harborages within 1.5 m of the host.^[2]

Because treatments are required in sleeping areas and other sensitive locations, methods other than chemical pesticides are in demand. Treatments can be costly, laborious, time consuming, repetitive, may entail health risks, and cause embarrassment to the person affected.

Pesticides

The pesticide approach often requires multiple visits and may not always be effective due to pesticide resistance and dispersal of the bed bugs. According to a 2005 survey, only 6.1% of companies claim to be able to eliminate bed bugs in a single visit, while 62.6% claim to be able to control a problem in 2-3 visits.^[3] Insecticide application may cause dispersal of bed bugs to neighbouring areas of a structure, spreading the infestation. Furthermore, the problem of insecticide resistance in bed bug populations increases their opportunity to spread. Studies of bed bug populations across the United States indicate that resistance to pyrethroid insecticides, which are used in the majority of bed bugs cases ^[4] is widespread.^[5] Exterminators often require individuals to dispose of furniture and other infested materials. It is advisable to break or mark these infested items to prevent their being unintentionally recycled and furthering the spread of bed bugs.

Disadvantages

Non-residue methods of mattress treatment are desired in place of contaminating mattresses with insecticides. Spraying the mattress with insecticide is undesirable as the room must be suitably ventilated, sufficient time must be given after application before the mattress can be used again and there is a risk of the user having an allergic reaction to the chemicals, not to mention other possible health risks including cancer ^[6] and acute neurotoxicity.^[7][8][9]

Concerns over the possible health effects of pesticides on people and pets, as well as the dispersal of bed bugs to neighbouring dwellings due to repellent effects of insecticides, make the practice of chemically treating the mattresses problematic.

Pesticide resistance

Bed bugs are developing resistance to various pesticides including DDT and organophosphates.^[10][11]

Some populations have developed a resistance to pyrethroid insecticides. Although now often ineffective, the resistance to pyrethroid allows for new chemicals that work in different ways to be investigated, so chemical management can continue to be one part in the resolving of bed bug infestations.^[12] There is growing interest in both synthetic pyrethroid and the pyrrole insecticide, chlorfenapyr. Insect growth regulators, such as hydroprene (Gentrol), are also sometimes used.^[13]

Populations in Arkansas have been found to be highly resistant to DDT, with an LD₅₀ of more than 100,000 ppm.^[14] DDT was seen to make bed bugs more active in studies conducted in Africa.^[15]

Bed bug pesticide-resistance appears to be increasing dramatically. Bed bug populations sampled across the U.S. showed a tolerance for pyrethroids several thousands of times greater than laboratory bed bugs.^[16] New York City bed bugs have been found to be 264 times more resistant to deltamethrin than Florida bed bugs due to mutations and evolution.^[17]

A population genetics study of bed bugs in the United States, Canada, and Australia using a mitochondrial DNA marker found high levels of genetic variation.^[18] This suggests the studied bed bug populations did not undergo a genetic bottleneck as one would expect from insecticide control during the 1940s and 1950s, but instead, that populations may have been maintained on other hosts such as birds and bats. In contrast to the high amount of genetic variation observed with the mitochondrial DNA marker, no genetic variation in a nuclear RNA marker was observed. This suggests increased gene flow of previously isolated bed bug populations, and given the absence of barriers to gene flow, the spread ofinsecticide resistance may be rapid.

Physical isolation

Isolation of humans is attempted with numerous devices and methods including zippered bed bug-proof mattress covers,^[19] bed-leg moat devices,^[20] and other barriers. However, even with isolated beds, bed bug infestations persist if the bed itself is not free of bed bugs, or if it is re-infested, which could happen quite easily.

Inorganic materials

Inorganic materials such as including boric acid and diatomaceous earth may be used in conjunction with other methods to manage a bed bug infestation, provided they are used in a dry environment. Upon contact with such dust-like materials, the insect's waxy outer layer of their exoskeletons is disrupted, which causes them to dehydrate.^[21]

Disposal of contaminated belongings

Disposal of items such as mattresses, box springs, couches etc. is a costly process and rarely solves the problem. Instead, new furniture is usually infested. The movement of infested furniture also facilitates the spread of bed bugs.

Vacuuming

Vacuuming helps reduce bed bug infestations, but does not eliminate bed bugs hidden inside of materials.

Cold treatment

Cold treatment offers an efficient inexpensive method of control. Bedbugs are highly temperature sensitive. They are adapted to live in sheltered indoor places with stable temperature and no air flow. If subjected to cold air and air flow their population number plummets over approximately a ten day period. To control a bedbug population using this method it is sufficient to place a few desktop fans on the floor around the bed or infested area, positioned to make sure there is a continuous circulating air flow in the whole area for at least 3-4 hours each day. A window should be kept well open, or air-conditioning used. Bite incidence typically goes down to 1-4 per month after ten days and stays at that level.

The advantage of the method is very low cost and effective control with reliable, stable outcome. However it does not appear possible to completely eradicate a bedbug population in this way. It is unclear whether this is because there always will be very small sheltered places left where founder populations can survive, or whether it is due to re-infestation from smaller populations elsewhere in the room, adjacent rooms, or brought in from outside. Bite incidence usually begins to increase around 3 weeks after the cooling regime is discontinued, and returns to the untreated level within a few months.

For complete eradication, freezing equipment is used to kill pests with cold temperatures. An example of this would be Cryonite, which uses the cooling properties of CO2, spraying a snow at a temperature of -78.5°C.^[22] Though bed bugs can tolerate a broad range of temperatures, -14 to 44 °C, they cannot survive body freezing or extreme heat.^[23] As with approaches such as vacuuming and steaming, freezing sprays may not reach bed bugs that are hidden inside walls, furniture or appliances.

Heat treatment

Steam

Steam treatment can effectively kill all stages of bed bugs. Unfortunately, bed bugs hide in a diversity of places, making steam treatment very tedious, labour intensive and time consuming. There is also the risk of the steam not penetrating materials enough to kill hidden bed bugs. The steam may also damage materials such as varnished wood, or cause mold from the moisture left behind. Requires repeated and very thorough steaming of the mattress, boxspring, bed frame, bed covers, pillows, not to mention other materials and objects within the infested room, such as carpets and curtains.

Clothes dryer

Clothes dryer can be used for killing bed bugs in clothing and blankets. Infested clothes and bedding is first washed in hot water with laundry detergent then placed in the drier for at least 20 minutes at low heat.^[24] However, this does not eliminate bed bugs in the mattress, bed frame and surrounding environment. Sterilized fabrics from the dryer are thus easily re-infested. Continually treating materials in this fashion is labour intensive, and in itself does not eliminate the infestation.

Room or building heat treatment

This method of bed bug control involves raising room temperatures to or above the killing temperature for bed bugs, which is around 45 °C.^[25][26] Heat treatments are generally carried out by professionals, and may be performed for a single dwelling or even to heat fumigate an entire building. Some of the drawbacks for heat treatments include the amount of time required to bring core temperatures high enough to effectively kill bed bugs that may have taken refuge within materials. This contributes to the professional heat treatments being generally expensive procedures.^[27] Following a heat-treatment, a room may be easily re-infested, as bed bugs are able to retreat into cracks and crevasses in walls, ceilings and floors, where they may escape treatment.

References

1. ^ Gangloff-Kaufmann, J.C. et al. 2006 Bed bugs in America: a pest management industry survey. Am. Entomol. 52: 105–106
2. ^ Harlan H. J. 2006 Bed bugs 101: the basics of Cimex lectularius. Am. Entomol. 52: 99–101
3. ^ Gangloff-Kaufmann J.C. et al. 2006 Bed bugs in America: a pest management industry survey. Am. Entomol. 52: 105–106
4. ^ Gangloff-Kaufmann J.C. et al. 2006 Bed bugs in America: a pest management industry survey. Am. Entomol. 52: 105–106
5. ^ Romero A. et al. 2007. Insecticide resistance in the bed bug: a factor in the pest's sudden resurgence? J. Med. Ent. Vol. 44, No. 2, pp. 175 – 178
6. ^ Alavanja MCR et al. 2003 Use of agricultural pesticides and prostate cancer risk in the Agricultural Health Study Cohort. Am. J. Epidemiol. 157:1–13
7. ^ Kaneko H, Miyamoto J. 2001 Pyrethroid chemistry and metabolism. In: Handbook of Pesticide Toxicology, Vol 2: Agents (Krieger R, Doull J, Ecobichon D, eds). San Diego:Academic Press, 1263–1288
8. ^ Narahashi T. 2001 Neurophysiological effects of insecticides. In: Handbook of Pesticide Toxicology. Vol 1: Principles (Krieger R, Doull J, Ecobichon D, eds). San Diego:Academic Press, 335–350
9. ^ Soderlund DM et al. Mechanisms of pyrethroid neurotoxicity: implications for cumulative risk assessment. Toxicology 2002;171:3–59
10. ^ "Pest Control Technology Magazine — July 2007". Pct.texterity.com. 2007-07-17. http://pct.texterity.com/pct/200707/?pg=50. Retrieved 2010-09-01. 
11. ^ C. Dayton Steelman, Allen L. Szalanski, Rebecca Trout, Jackie A. McKern, Cesar Solorzano & James W. Austin (2008). "Susceptibility of the bed bug Cimex lectularius L. (Hemiptera: Cimicidae) to selected insecticides". Journal of Agricultural and Urban Entomology 25 (1): 45–51. doi:10.3954/1523-5475-25.1.41. 
12. ^ Insecticide Resistance in the Bed Bug: A Factor in the Pest’s Sudden Resurgence? Alvaro Romero, Michael F. Potter, Daniel A. Potter, Kenneth F. Haynes Journal of Medical Entomology 2007 44 (2), 175-178
13. ^ "How to Manage Pests Pests of Homes, Structures, People, and Pets". UC IPM Online (Statewide Integrated Pest Management Program, UC Davis). http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7454.html. Retrieved 26 June2010. 
14. ^ C. Dayton Steelman, Allen L. Szalanski, Rebecca Trout, Jackie A. McKern, Cesar Solorzano & James W. Austin (2008). "Susceptibility of the bed bug Cimex lectularius L. (Hemiptera: Cimicidae) to selected insecticides". Journal of Agricultural and Urban Entomology 25 (1): 45–51. doi:10.3954/1523-5475-25.1.41. [1]
15. ^ "DDT and Africa's war on malaria". BBC News. November 26, 2001. http://news.bbc.co.uk/2/hi/africa/1677073.stm. Retrieved April 26, 2010. 
16. ^ Voiland, Adam"You May not be Alone" U.S. News & World Report 7/16/2007, Vol. 143, Issue 2, p53–54.
17. ^ "Biochemical and Molecular Analysis of Deltamethrin Resistance in the Common Bed Bug (Hemiptera: Cimicidae)" Journal of Medical Entomology,45 (6), 2008, pp. 1092–1101
18. ^ Szalanski, A.L., J.W. Austin, J.A. McKern, C.D. Steelman, and R.E. Gold. 2008. Mitochondrial and ribosomal internal transcribed spacer (ITS1) diversity of the bed bug Cimex lectularius L. (Heteroptera: Cimicidae). Journal of Medical Entomology 45: 229-236. [2]
19. ^ http://www.pestservices.ca/miscproductsdetails.aspx?mpid=7&cat=Mattress Accessed: 27-04-2011
20. ^ http://bedmoat.com/order/ Accessed: 27-04-2011
21. ^ Insects in the City, Texas A&M
22. ^ www.cryonite.net/images/stories/pdf/cryonite_manual_pro_en_lo.pdf Accessed 27-04-2011
23. ^ Benoit, JB et al. 2009. Responses of the bed bug, Cimex lectularius, to temperature extremes and dehydration: levels of tolerance, rapid cold hardening and expression of heat shock proteins. Vol. 23(4): 418- 425
24. ^ Armed Forces Pest Management Board. 2006. Bed bugs – importance, biology, and control strategies. Washington, DC: Armed Forces Pest Management Board Technical Guide No. 44.
25. ^ www.thermapure.com/pr_Heat_to_Kill_Bed_Bugs.php Accessed: 27-04-2011
26. ^ Harlan, H.J. 2006. Bed bugs 101: the basics of Cimex lectularius. American Entomologist. Vol. 52(2): 99-101)
27. ^ http://waronbedbugs.blogspot.com/2007/05/heat-and-cold-treatment.html