Bedbug
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 Cimex lectularius
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Genera & Species
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Genus Cimex
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Bedbugs (or bed bugs) are small nocturnal insects of the family Cimicidae that live by hematophagy, feeding on the blood of humans and other warm-blooded hosts.
Biology
Genera and species
The common bedbug ( Cimex lectularius) is the best adapted to human environments. It is found in temperate climates throughout the world and has been known since ancient times.
Other species include Cimex hemipterus, found in tropical regions (including Florida), which also infests poultry and bats, and Leptocimex boueti, found in the tropics of West Africa and South America, which infests bats and humans. Cimex pilosellus and C. pipistrella primarily infest bats, while Haematosiphon inodora, a species of North America, primarily infests poultry.
Oeciacus, while not strictly a bedbug, is a closely related genus primarily affecting birds.
Physical characteristics
Adult bedbugs are reddish brown, flattened, oval, and wingless, with microscopic hairs that give them a banded appearance. A common misconception is that they are not visible to the naked eye, but adults grow to 4 to 5 mm (one-eighth to three-sixteenths of an inch) in length and do not move quickly enough to escape the notice of an attentive observer. Newly hatched nymphs are translucent and lighter in colour and continue to become browner and molt as they reach maturity. When it comes to size, they are often compared to lentils or appleseeds.
Feeding habits
Bedbugs are generally active only at night, with a peak attack period about an hour before dawn, though given the opportunity, they may attempt to feed at other times of day. Attracted by warmth and the presence of carbon dioxide, the bug pierces the skin of its host with two hollow tubes. With one tube it injects its saliva, which contains anticoagulants and anesthetics, while with the other it withdraws the blood of its host. After feeding for about five minutes, the bug returns to its hiding place. The bites cannot usually be felt until some minutes or hours later, as a dermatological reaction to the injected agents. Although bedbugs can live for up to 18 months without feeding, they typically seek blood every five to ten days.
Bedbugs are often erroneously associated with filth. They are attracted by exhaled carbon dioxide, not by dirt, and they feed on blood, not waste. The cleanliness of their environments has no effect on bedbugs.
While bedbugs have been known to harbor pathogens in their bodies, including plague and hepatitis B, they have not been linked to the transmission of any disease and are not regarded as a medical threat. Some individuals, however, can get skin infections and scars from scratching bites. While bedbugs are not regarded as a vector of transmissible diseases, they are a serious stressor and will create a lot of alarm and distress. With some individuals, it may precipitate mild to moderate cases of delusory parasitosis.
Reproductive habits
Female bedbugs can lay up to five eggs in a day and 500 during a lifetime. The eggs are visible to the naked eye measuring 1mm in length (aprox. 2 grains of salt) and are a milky-white tone in colour.
A few bedbug species make use of a mating plug, secreted by the male upon withdrawal after copulation, effectively gluing shut the vaginal opening of the female against later males. Among such species, the male impales the female via her abdomen, thus circumventing a mating plug.
In Xylocaris maculipennis, the male will at times impale and inseminate other males while they are engaged in the process of copulation. This allows the impaler's genes to enter the bloodstream to be carried to females by the victim. In this way, the impaler conceives by proxy. In A Natural History of Sex, Adrian Forsyth writes, "The sperm of the rapist enters the vas deferens of his male victim and is used by the victim during copulation." This also occurs with fresh water snails of the genus biomphalaria, which are vectors for schistosomiasis (Forsyth 1991).
Infestations
Incidence of infestations
With the widespread use of DDT in the 1940s and '50s, bedbugs all but disappeared from North America in the mid-twentieth century. Infestations remained common in many other parts of the world, however, and in recent years have begun to rebound in North America. [1] The insects have become epidemic in the Boston neighborhoods of Allston and Brighton, Massachusetts, where in 2004 renters were offered subsidies to replace infested mattresses. [2] As a bedbug infestiation is almost never limited to matresses or bedding, this remedy will be less than effective. Reappearance of bedbugs in the developed world has presented new challenges for pest control, and, without DDT and similarly banned agents, no fully effective treatment is now in use. The industry is only beginning to develop procedures and techniques.
Another reason for their increase is that pest control services more often nowadays use low toxicity gel-based pesticides for control of cockroaches, the most common pest in structures, instead of residual sprays. When residual sprays meant to kill other insects were commonly being used, they resulted in a collateral insecticidal effect on potential bedbug infestations; the gel-based insecticides primarily used nowadays do not have any effect on bedbugs, as they are incapable of feeding on these baits.
The Professional Pest Management Association, a US advocacy group for pest control operators (PCOs) conducted a "proactive bed bug public relations campaign" in 2005 and 2006, resulting in increased media coverage of bedbug stories and an increase in business for PCOs, possibly distorting the scale of the increase in bedbug infestations. [3].
Method of initial infestation
There are several means by which dwellings can become infested with bedbugs. People can often acquire bedbugs at hotels, motels, and bed-and-breakfasts, thanks to increased domestic and international tourism, and bring them back to their primary domiciles in their luggage. They also can pick them up by inadvertently bringing infested furniture or used clothing to their household either via purchase or " dumpster diving". If someone is in a place that is severely infested, bedbugs may actually crawl onto and be carried by people's clothing, although this is atypical behaviour — except in the case of severe infestations, bedbugs are not usually carried from place to place by people on clothing they are currently wearing. Finally, bedbugs may travel between units in multi-unit dwellings (such as condominiums and apartment buildings), after being originally brought into the building by one of the above routes. This spread between units is dependent in part on the degree of infestation, on the material used to partition units (concrete is a more effective barrier to the spread of the infestation), and whether or not infested items are dragged through common areas while being disposed of, resulting in the shedding of bedbugs and bedbug eggs while being dragged.
Common location of infestations
Bedbugs are very flat, allowing them to hide in tiny crevices. A crack wide enough to fit the edge of a credit card can harbor bedbugs. In the daytime, they tend to stay out of the light, hidden in such places as mattress seams, mattress interiors, bed frames, nearby furniture, carpeting, baseboards, or bedroom clutter. Bedbugs can settle in the open weave of linen; this will oft appear as a gray spindle a centimeter long and a thread wide, with a dark speck in the middle. Although bedbugs may be found on an individual basis, they more often congregate and nest in groups, although they do not behave in a cooperative, "groupmind" fashion such as one might find in nests of ants, bees, or termites. Bedbugs are capable of travelling as far as 100 feet to feed, but usually remain close to the host in bedrooms or on sofas where people may sleep. They feed every five to 10 days. The manner in which infestations spread throughout a domicile is not entirely understood and differs from case to case.
Size of infestations
Some pest control professionals have deemed light infestations to be anything below 200 bedbugs in a residence, medium infestations to be in the range of 200–300 bedbugs in a residence, and severe infestations to be as bad as 2,000–3,000 bedbugs in a single residence.
Detection of infestations
Bedbugs can be detected often by looking for black tracks on bedding, which are the bedbugs' fecal stains. These stains are most visible on light-colored bedding.
Occasionally an engorged bedbug is inadvertently killed or disgorged by incidental crushing, resulting in a visible smear of blood. Crushing them will produce a unique sickly sweet pheremone scent, which can also be detected in the ambient air in a severe infestation.
Though bedbug bites can occur singly, they often follow a distinctive pattern of a linear group of three bites, sometimes macabrely referred to as "breakfast, lunch and dinner". The effect of these bites on humans varies from person to person, but often cause welts and swelling that are more itchy and longer-lasting than mosquito bites. Some people, however, have little or no reaction to bedbug bites. Those whose bodies do not initially react may subsequently develop symptoms, however, due to an allergic reaction caused by the development of antigen. A technique for "catching" (detecting) bedbugs is to have a light source accessible from bed and to turn it on at about an hour before dawn, which is usually the time when bedbugs are most active. A flashlight is recommended instead of room lights, as the act of getting out of bed will cause any bedbugs present to scatter. Bedbugs can also sometimes be viewed during the day.
Some individuals have used glue traps placed in strategic areas around their domicile (sometimes used in conjunction with heating pads, or balloons filled with exhaled breath, thus offering the carbon dioxide that bedbugs look for) in order to attract and thus detect bedbug infestations. There are also commercial traps like "flea" traps whose effectiveness is really questionable except perhaps as a means of detection, but traps will certainly not work to control an infestation.
Veterinarians may mistake bedbugs' leavings on a pet's fur as "flea dirt".
The above having been said, bedbugs are known for being elusive, transient and nocturnal. For many, the only way to detect and identify with certainty an infestation is to contact a pest control professional.
Living with infestation
If it is necessary to live with bedbugs in the short term, it is possible to create makeshift temporary barriers around a bed. Because bedbugs cannot fly or jump, an elevated bed can be protected by applying double-sided sticky tape (carpet tape) or petroleum jelly around each leg, or by keeping each leg on a plastic furniture block in a tray of water. A bed frame can be effectively ridded of adult bedbugs and eggs by use of steam. Small steam cleaners are available and are very effective for this local treatment. A suspect mattress can be protected by wrapping it in a painter's disposable plastic dropcloth, neatly sealing shut all the seams with packing tape, and putting it on a protected bed after a final visual inspection. Bedding can be sanitized by a 120° F (49° C) laundry dryer. Once sanitized, bedding should not be allowed to drape to the floor. An effective way to quarantine a protected bed is to store sanitized sleeping clothes in the bed during the day, and bathing before entering the bed.
Vermin and pets may complicate a barrier strategy. Bedbugs prefer human hosts, but will resort to other warm-blooded hosts if humans are not available, and some species can live up to eighteen months without feeding at all. A co-infestation of mice can provide an auxiliary food source to keep bedbugs established for longer. Likewise, a house cat or human guest might easily defeat a barrier by sitting on a protected bed. Such considerations should be part of any barrier strategy.
Treatment
Self-treatment
Some individuals have had success conducting their own exterminations by preparing an insecticide mixture of pyrethrins and fresh-water diatomaceous earth. At least one manufacturer produces a household insecticide D-20 with only .2% naturally derived pyrethrins and 1.0% Piperonyl Butoxide, which magnifies the pyrethrins effectivenes by 10 times. Natural pyrethrins are more expensive than many alternatives. The function of the pyrethrins is to stimulate the nervous system of the bugs so that the spasms will allow the diatomaceous earth to dessicate, puncture, and kill the bugs through mechanical action. Great care should be taken not to use products with salt-water diatomaceous earth or heat-treated diatomaceous earth, which can damage the lungs of any mammal (dogs, cats, or humans) which inhale it, and has also been known to cause cancer. Fresh-water diatomaceous earth, however, is commonly used to deworm cats, dogs, and humans, and is considered as safe as table salt.
Others have used fruit and vegetable insecticides, comprised of a mixture of pyrethins and canola oil, which are usually safe for humans and most pets (aside from fish).
Contrary to popularly disseminated information, extreme heat or extreme cold is usually not effective in eliminating bedbugs. Pest control professionals receive reports of infestations even in the dead of winter, and manufactured environments of extreme heat or cold (such as encasing a mattress in a bag and placing it in direct sunlight, or placing a suspect piece of bedding or clothing in a freezer) usually cannot stay consistently hot or cold enough to sufficiently kill bedbugs, which are not particularly sensitive to temperature extremes. In addition, since bedbugs normally disperse, treatment of a bed or mattress is insufficient to eradicate an infestation.
Professional treatment
Selection of professionals
Due to their absence from North America for several decades, not all exterminators in that region are familiar with extermination techniques for bedbugs. Those who are unfamiliar with bedbug extermination techniques may attempt to use ineffectual techniques, such as fumigation. Care must thus be taken when selecting an exterminator, in order to select a professional that knows how to conduct proper bedbug removal. The National Pest Management Association can assist in the location of pest control professionals.
Necessary number of professional treatments
An informal survey of pest control professionals conducted by a pest control professor at the University of Massachusetts stated that 68% of all bedbug infestations require three or more treatments, 26% require two treatments, and 6% require just one. [4] However, this survey does not seem to have taken into account the size of the infestation, the size of the venue being treated, the extensiveness of that venue's preparation for the treatment (thus enabling or inhibiting coverage of the poisons), the skill of the exterminator, whether popular nesting places have been disposed of, and the cause behind the original infestation.
Pre-treatment
Most exterminators require that the domicile be prepared by residents prior to their arrival for a chemical treatment. If an exterminator does not ask a client to prepare, then they would be suspect unless they offered to do the preparation. This would be rare except if a client were willing to pay a considerable sum for this service.
Packing
All furniture and appliances in the dwelling usually need to be pulled away from the baseboards, and it is commonly asked that all furniture containing potential hiding crevices, such as bookshelves and desks, be emptied and left open for the exterminator to spray. Items in tightly sealed containers are usually safe from bedbug infestation and need not be emptied.
Laundry
Everything possible should be laundered, such as clothing, rugs and stuffed toys. For maximum effect, laundry should be handled in a coordinated attack, shortly before or after a pesticide treatment. The entire household's laundry should be securly tied into plastic bags all at one time, and brought back into the home only after the living space has been treated. Dry cleaners should be informed of an infestation, and items should be properly bagged when delivered to a dry cleaning service. Laundered objects should be encased in securely tied garbage bags until they reach the laundry machine, and the bags should be discarded. Whenever practical, hot water and a 120° F (49° C) drying session extended by a few extra minutes are preferred. As extensive laundering of clean clothes may pose an excessive cost for some, drying clothing alone is completely effective in killing all stages. Laundering the clothes is then an aesthetic that makes some people feel better, but it is not necessary if the drying is done at medium to high heat for at least 20 minutes. Allow for time for the dryer to heat the clothes as the 20 minute to kill all stages is at the medium to high heat as noted above.
Vacuuming
The mechanical removal of bedbugs by vacuuming is a most important part of preparing for control. Vacuuming alone will not solve the problem, but it definitely can reduce bedbugs' numbers and thus help reduce the population as part of preparing for treatment. A crevice attachment should be used on the seams of mattresses, on box springs, on bed legs, on mattresses, box springs, within furniture interiors, behind pictures, on curtains, and anywhere there is a possibility of the insects hiding (e.g. inside dresser drawers, dresser cases, under chairs, etc.). Carpets should also be vacuumed throughout the home, preferably with a power-head. Baseboards should also be vacuumed using the crevice tool — not swept — prior to the exterminator's arrival, and the filter should be immediately removed and discarded outdoors.
Steam Treatment
Some pest control firms do offer steam treatment for items like mattresses or upholstered furniture especially when individuals are concerned about pesticides on bedding. This has only a very limited effectiveness however, it is quite effective in this range of less than 1/2 inch of penetration. This also depends on the time that the steam is applied to the surface of the item. Small steam cleaners for domestic use can be useful for mattresses and the surfaces of upholstered furniture. This is a worthwhile option if there are issues of allergy, and the homeowner takes the time to treat carefully in this limited context.
Managing Bedding
There are differing opinions as to whether it is necessary to dispose of mattress, boxsprings, futons, pillows, and other bedding. There is of course often a heavy cost involved in the complete replacement of such bedding. A decision as to whether to replace bedding or not can depend on the condition of and often related level of infestation within the items, the comfort level of the owner, whether the owner can afford replacement, and aesthetics. Treatment of these items must be done with care and according to the label. Mattresses typically need local treatment with non-residual insecticides at seams and borders. Boxsprings are more difficult to treat as there are more places for the insects to hide.
After the mattress and/or box spring or futon has been treated, placing these inside a cotton or a polyvinyl or polyethylene bag is a good idea as a secondary means of defense. Bedbugs like to hide near the victim and are commonly found on seams of mattreses, or within the structure of box springs. The mattress bag serves to reduce this likelihood and in the case of box springs, it seals any remaining insects inside the bag. The mattress bag also protects the mattress from the mess of staining caused when bedbugs aggregate on seams. The bag is a good idea either until the infestation has been totally eliminated or in the case of good quality cotton bags, useful as a permanent protection for the mattress - and also to enable easier control if infestation recurs.
Those who end up disposing of suspect items should enclose them in plastic mattress bags, or large garbage bags, to prevent shedding bugs and eggs on their way to the disposal site. Care should also be taken to label throwaway items with a warning about the suspected bedbug infestation, as furniture is often reclaimed by dumpster divers.
New items should not be purchased until after the infestation has been thoroughly eliminated. Also, many retailers offer disposal of old mattresses. This can pose obvious problems if new and old mattresses are carried together on the same truck without the proper precautions taken.
Treatment
Exterminators will often apply a "contact kill" spray directly on bedbugs found in the apartment (such as a mixture of cyfluthrin, pyrethrins, and piperonyl butoxide), and then spray lambda-cyhalothrin on baseboards and other favorite hiding places. Lambda-cyhalothrin acts as a "slow kill" barrier which kills bedbugs after they cross it, and is usually microencapsulated, making it safe to pets and humans after it dries. Often, deltamethrin is also injected into larger crevices. The lambda-cyhalothrin and the deltamethrin are at their strongest for the first two weeks following their application, but usually retain effectiveness for up to 60 days.
Gentrol and Phantom can also be used for bed bug control. Gentrol contains the active ingredient (S)-Hydroprene, an insect growth regulator (IGR) that disrupts the normal growth development of cockroaches and stored product pests, drain flies and fruit flies, as well as bed bugs. Phantom® uses an active ingredient known as chlorfenapyr. It is non-repellent and relatively long-lasting.
Successful treatment of a bedbug infestation is often highly dependent on how thorough the pest control professional is. Although the assessment and judgment of the pest control professional should be respected, most treatments cover such areas within domiciles as closets, curtains, outside and inside furniture crevices (dresser and desk drawers, night tables, etc.), as well as the interior of electrical outlets and behind pictures hangings on walls. If the choice was made to retain bedding, professionals will often either treat or steam-clean bedframes and the undersurface of solid beds. Some higher-end pest control firms also offer to perform the aforementioned vacuuming.
Post-treatment
Bedbugs can often be seen alive for up to two weeks following treatment of a dwelling, although they should not be seen in great number (e.g., only one or two). It is important to continue to monitor for bedbugs after the initial treatment.
Vacuuming should not be performed for a period of time following treatment, as some pesticides dry as a fine film, and can be prematurely removed from the environment if vacuumed, allowing infestations to survive the treatment.
Anecdotal evidence within the blogging community seems to suggest that many, and perhaps most, people who successfully deal with bedbug infestations find themselves overly paranoid about the possibility of reinfestation for varying lengths of time. These feelings of anxiety may have some relation to delusory parasitosis: "Sometimes an initial and real insect infestation precedes and triggers the delusion [...] Out of desperation the victims may move out of their home, only to report later that the ‘bugs’ have followed them there too." (The Physician’s Guide to Arthropods of Medical Importance, J.A. Goddard, CRC Press, 1993.)