Bed Bugs: Domestic Terrorist

Bed Bugs: Why they are they back? What to do?

Introduction

Bed bugs were a thing of the past, heard only in parent’s warning to child before going to bed [“Good night, don’t let the bed bugs bite!”]. [That, by the way, is an expression that reminds us of a time before pesticides when bed bugs were extremely common] In the old days, exterminators would be called in to dose the mattress and bed material with a white powder, the infamous DDT, and bedbugs would be vanquished. With the removal of DDT as an weapon against these pests, the switch to baiting to control other interior pests and the political correct removal of the term exterminator, pest management professionals (PMPs) don’t have a quick fix for these annoying pests. Although their health significance is not alarming; Bed bug bites do not carry disease in the way mosquitoes or fleas do, bedbugs are certainly a growing problem in the hotel industry and in homes.
There probably isn’t a better alarm for a pest problem than one that originates in the Big Apple. Another significant invader entered New York City in the last years of the 90s that brought with it the crisis that would only be appropriate for the New York media. West Nile Virus, found in birds, transmitted by mosquitoes and potentially deadly in only the very young or very old, caused as much realistic scare as a horror flick such as “I know What You Did Last Summer” or one of its sequels. In the case of bed bugs, while their health significance is not large, their reemergence is widespread and interesting. I will discuss bed bug identification, biology and behavior, the background of their reemergence, the inspection process, physical techniques and treatments to prevent infestations and other issues that deal with bed bugs as a growing problem within our industry along the way.

Common Bed bug Identification

Bed bugs [Cimex lectularis] are insects that feed primarily on human blood, although they are known to target other animals like birds and rodents. The adult is a ¼” long; oval shaped and doesn’t have any wings. Bed bugs have very flat bodies covered with tiny hairs. It is brownish-tan, unless filled with blood after feeding. Because the life cycle in incomplete, or hemimetabolous in “bug-speak”, the nymphs look very similarly as the adults although they tend to be lighter in color. Normally, the adults are first to be discovered because the nymphs are very small in size. It has been said that for every adult that is spotted, there are nine nymphs that remain unseen.

Biology and Behavior

Bed bugs feed at nighttime, usually when the unsuspecting (or suspecting if the infestation is already known) host is sleeping. Feeding, called engorging, takes less than ten minutes, done in three consecutive blood meals. Like other blood-feeding insects, bedbugs salivate into the host to stop the blood from coagulating inside the wound. Therefore the blood can be sucked up through the inserted proboscis (feeding apparatus). Reactions to a bed bug bite range from none to severe. It is the saliva of the bed bug that causes the host to itch the bite. The most dangerous health risk now from bed bug bites, besides allergic reaction, is itching the wound and potential infection by bacteria. The effects of a feeding bunch of bed bugs can be impressive. With a colony raised by a colleague of mine, a white mouse was completely drained of blood and killed within ten minutes by the hungry bed bugs.
One male can impregnate several females in a day. Once gravid, a female can lay up to five-hundred eggs in a lifetime. A female lays eggs up to eight eggs at a time in rough surfaces, corners, cracks and crevices near adult harborages. They are glued by a cementing substance to the surfaces. Eggs are 1/25” long [or short], curved somewhat and hatch in six to ten days depending on environmental conditions. Under optimal conditions (~80% humidity and ~ 90 F) the life cycle takes four to five weeks from egg to egg. This time is greatly reduced when either temperature or humidity is reduced. At low enough temperatures, bed bugs stop reproducing entirely and feeding is greatly reduced, although one scientist noted populations of active bed bugs at 45 F. Life-span is nearly a year and adults and nymphs can live for several months without feeding.
Groups of bed bugs are commonly found together and use aggregation pheromones, similar to social insects, to communicate. They prefer finding harborage close to the host and make themselves quite cozy in cracks and crevices near or on bed frames, the box spring and the mattress. Wherever they can fit they will go. However, bed bugs will travel far to find harborage or new hosts. This increases the difficulty of locating and treating bed bugs. Bed bugs have found to prefer wood surfaces rather than metal and travel away from iron frames to seek adequate harborage.

Medical Un-importance

Although bedbugs are not known to transmit disease, there is some medical importance to bed bug bites. Like mosquitoes, bedbugs cannot transmit HIV. (Mosquitoes transmit a lot of other diseases though) Severe itching and inflammation are known to follow some bed bug bites. Asthmatic symptoms have been recorded with people sensitive to allergens. People who are bitten repeatedly have been known to develop a syndrome that makes them to be jumpy, lose sleep and constantly be nervous. There is no realistic risk of blood loss as a factor because it would take unheard of populations of bedbugs to suck that much blood. Often it is the embarrassment of having bed bugs in a home or a hotel that is most damaging. Compare if you will, a kid found with head lice in school. Forget friends, even enemies will avoid him/her like the plague. Back to bed bugs; who wants to stay at a hotel known for bed bug infestation at any cut rate, or stay with a friend with bed bugs in their home? What a disastrous social pest bed bugs can be!

“[Bed bugs were] once…a major pest of hotels and home” (1997)

This quote was written just nine years ago by a bed bug entomologist. Bed bugs were virtually non-existent in the mind of the pest control industry less than a decade ago. Now it seems discovery of bedbugs are shown in headline to headline in every state in the United States. This doesn’t sound like a problem that has gone away. The tourism industry has been crippled by millions in losses. The problem has by no means been limited to the United States alone. This reemergence has been seen across the globe from Canada to Australia. In Australia, estimates of $100 million annual losses have been reported in the tourist accommodation industry.
It appears that the resurgence of bed bugs is the result of a number of different reasons. An increase in travel for both business and leisure, a change in pest control practices and overall negligence in dealing with infestations as they appear have helped bed bugs become reestablished over the world. However, the bedbug story is not as simple as disappearance and now, reemergence.
Before World War Two, infestations were exceedingly common. More than four million people had problems with bed bugs in Greater London alone. Quite a remarkable discovery was made by Swiss scientist Paul Hermann Müller in 1939. A chemical called dichlorodiphenyltrichloroethane, or DDT, was found to kill insects. Originally used to protect against the spread of malaria and typhus, DDT worked so well against mosquitoes, fleas and lice its use was widened for many pests. Even though health and environmental concerns spearheaded by Rachel Carson’s book Silent Spring (1962), eventually had DDT recalled from use (and the creation of the EPA in 1972), the effects of DDT to pests were inspiring. Malaria was dramatically reduced across the world and typhus was virtually eliminated by widespread spraying of DDT. Curiously, because of DDT sprayed indoors to kill resting mosquitoes (mosquitoes rest on walls following a bloodmeal), populations of bed bugs along with other unwanted insect pests were killed in the process.
After its recall, chemical companies realized the profits that could be made in developing suitable replacements for DDT, although it is still used in the tropics to control the problem of malaria (300 to 500 million infected annually). Many different classes of pesticides followed DDT to treat indoor pests, however all were applied to an area. Bed bugs were specifically treated with powder spread generously over mattress material, box springs and around the bed. With the development of baiting, the general pesticides that had once treated for all insects became specific for cockroaches (the primary indoor pest). Because bedbugs feed on blood, the baits would not affect them. Bed bugs peeped out from their hiding places and by one infestation at a time, have moved slowly at first, and now swiftly back into hotels and homes. Because of their tendency to get inside of luggage, clothing, bags and other travel accessories, bed bugs score free rides back with a traveler. Bed bugs also hide in furniture and bedding so spreading can occur because of the purchase of used furniture. Maybe that bed or couch that looks gorgeous on the corner of the street should not be picked up and brought home: There’s a reason it’s being thrown away. Bed bugs! With the coming of better technology for traveling over the last few decades, these hitchhiking bugs have found more frequent travel around the globe.
Note: Bed bugs are found infesting places other than those thought of as traditional. In 2005 in Italy, 3000 train cars were found infested with bedbugs. Apparently travelers catching Z’s on overnight trains in Italy were tasty meals for Italian bed bugs. Many of these train cars were destroyed because there was no way to rid them of the nuisance.

Inspecting for Bed bugs

The visual inspection for bed bugs is the only reliable method at the present time. Sticky traps and other monitoring devices have not been found to be particularly effective and there are no systems specifically designed for bed bugs available currently. Bedbug inspection is similar to inspection for German cockroaches. Bed bugs are night feeders, so specimens are unlikely to be encountered during a daytime inspection. Instead, inspectors should look for telltales. Telltales are usually cast skins and fecal smears that resemble brown or black staining underneath the surface of harborages. Upon closer inspection, egg shells and even life specimens can be spotted just like for German cockroaches. Another great indicator of bed bug blood feeding is the blood smears that are left on the mattress.
Identification of the actual pest and location of the harborages is essential for the success of a treatment program. When bed bugs first infest, it starts with just one a few individuals. These bugs remain close to the feeding sites and do not actively seek other areas to invest. Once infestations become larger, bed bugs find shelter gradually farther from hosts. Reading up on some inspections it became clear to me that knowledge of the customer’s habits are as important as locations of sleeping areas.
These examples highlight the need for knowing the client’s habits:
Inspection of the sleeping area of a child turned up very few specimens even though the child had been complaining of frequent bed bug bites. When the child’s late night TV viewing habits were considered, inspection of the couch and cushions in front of the TV uncovered hundreds of bed bugs. Another case involved an older gentleman who was complaining of frequent bed bug bites. Inspection of the beds and couches yielded nothing until a look into his closet revealed a pullover sweatshirt with hundreds in its pockets and sleeves. In some cases, the harborage is not found in the beds and couches but in items not initially inspected, such as, blankets, night garments and covers.
A sign for a heavy infestation of bed bugs is a sweet, characteristic odor. This smell comes from secretions from bed bugs’ hind legs. As the infestation grows in number and in area, the secretions become more widespread making this distinct smell.

Physical Control

Once harborages are discovered and specimens identified as bed bugs, steps to control the infestation begin. The days of spray and pray are over. There are no magic bullets in the form of pesticides available for bed bugs as there are for ants and termites (fipronil). In dealing with bedbugs, there is a strong need for customer cooperation, perhaps more so than for any pest insect. There is no all-encompassing pesticide that is registered for complete interior application. Customers of pest service are almost as responsible for a failed treatment for bed bugs as the pest control service treating them.
There are many ways to protect one-self against these annoying creatures without using pesticides. As always, prevention of infestations is the best method. The best way to prevent bed bugs infestations is to have frequent inspections for them. If items are found to have bed bugs during inspection, they should be washed, given cold/heat treatment, fumigated or disposed of. This holds true for the hotel industry or people buying used furniture. Prevention by frequent inspection and ‘de-bugging’ methods before the furniture is brought into the home or hotel could save dollars and time in the long run. A habit of hotel managers “to move the problem” to another hotel room only helps bed bugs become more established!
However, even after large infestations of bed bugs have occurred, there are ways to limit them. If bed bugs are in the mattress, there are several options. Obviously getting rid of the mattress set will help but you can also steam ALL surfaces of the mattress (220 F) being particular around folds and grooves. Check the entire bed set. Steam the bed frames headboard, box spring etc to kill bed bugs that have left the mattress. Once the complete bed set is steamed, place the posts of the bed in plastic dishes. Bed bugs cannot climb like flies because they lack the same pads on their feet and cannot climb on plastic cups. Make sure to wash sheets and linens in hot water…and don’t wait…bedbugs do wander. Bed bugs will still be present in the room but cannot climb up into the mattress. Efforts should be made to keep blankets, sheets, pillows off the floor. Still, bed bugs have been known to climb up onto walls and ceilings and drop onto the bed from above! Sites on, around, and near the bed that could potentially harbor bed bugs should be vacuumed. Sealants and caulking can be used to close cracks in walls and floors. This requires great detail…bedbug nymphs can readily use very small cracks for harborage. Limiting harborage increases the distances bed bugs will have to crawl to reach hosts. With the increase in distance comes the increase in chances it will contact pesticides used or be spotted. Another method of introduction that has recorded has been through birds and rodents. The common bedbug prefers human hosts but will not limit its feeding to humans alone. Birds and bats or mice etc can readily provide bloodmeals for bed bugs.
Ways not to physically control bedbugs include the following: as said before, moving hotel guests to another room after reports of being bitten by bed bugs. Another method that has shown no success is quarantining the room for weeks or even months. Bed bugs can wait out for more than a year without a bloodmeal. Vacating the room for weeks or months just delays the problem. Control of this pest requires cooperation from the customer. Removing harborages, such as cracks and crevices, and reducing clutter around the feeding sites are essential in controlling bed bugs. Lastly, the recycling of thrown out furniture because of previous bedbug infestations guarantees the spread of bed bugs. Perhaps furniture should be labeled with a sign that will ensure all but the blind won’t take it off the curb… “Don’t Touch, Bed bugs!”

Chemical Treatment

Pesticide treatment for bed bugs can be divided into how they are used. There are four different categories; Crack and Crevice, Indoor Surface, Indoor Space, and Fumigation. (A good chart of available pesticides labeled for use against bedbugs is listed on table 1 at http://edis.ifas.ufl.edu/IG083) Treatment of mattress surfaces and bedding material really should never be done. There are non-pesticide methods that can kill bed bugs on these surfaces. Remember, the best way to treat for bed bugs is with chemicals in combination with physical techniques.
Chemicals should be directed to harboring sites. This includes all the cracks and crevices, holes, BEHIND electrical outlets (never put treatments inside electrical outlets), behind pictures and paintings, in drawers and behind nightstands, underneath carpets, especially behind and under tacking strips, behind wood trim, on light fixtures and on the base of ceiling fans, in wall voids between adjacent rooms etc. It is essential that all areas of harborage are treated to eliminate populations.
Crack and Crevice application is the most effective treatment for eliminating harborage sites. Usually using a dust or spray, these treatments can reach difficult locations. This should be the treatment of choice for all harborages and potential harborages found in an infested space.
Indoor surface treatments are used to create dead-zone for bed bugs crawling to and from harborages to the host. Application of this kind relies on residual sprays applied to surfaces around the bed to give a longer lasting protection against wandering bedbugs. Indoor space treatments are used to kill insects that are spotted. When a bed bug is seen, an aerosol, most commonly, is sprayed in its direction to kill it.
If all else fails and the infestation is beyond any kind of careful treatments and physical techniques, fumigate. Fumigation is very expensive and is almost always unnecessary. However, taking infested items that cannot be cleaned by other methods, such as furniture, box springs, electrical devices etc, and placing them in a fumigation chamber is very effective at removing these unwanted guests.
After doing any kind of chemical treatment for a customer, it is always necessary for a follow up. Of course, it makes your pest control service look better, but in the specific case of bed bugs and their shy behavior, re-infestations are common. Although it is possible for a brand new infestation from an outside source, but more likely not every harborage was treated and bed bugs have made a comeback in the treated house. It is in these cases where customer cooperation and dedication to the treatment program are most important to eliminate the pests.

Sources

Bed-bug epidemic bites at Austalian tourism. 2-3-2006. http://today.reuters.co.uk/news/

Bed Bug Problem Annoys Residents. 2-12-2006. http://www.channelcincinnati.com/news/

Cimex lectularis Linnaeus: The Bed Bug. 2006 http://www.thesahara.net/bed_bug.htm

Cooper, R.A and H Harlan. 2003. Bed Bugs and Kissing Bugs in Handbook of pest control: the behavior, life history and control of household pests (Mallis A., and S. Hedges, eds.) 9th ed. GIE Media, Inc.

Jupp, P.G and Lyons S.F. 1987. Experimental assessment of bedbugs (Cimex lectularius and Cimex hemipterus) and mosquitoes (Aedes aegypti formosus) as vectors of human immunodeficiency virus. AIDS, 1(3): 171-4.

Koehler, P and J Hertz. 2005. University of Florida IFAS extension, Bed Bugs and Blood-Sucking Conenose. http://edis.ifas.ufl.edu/IG083

Potter, M. 2006. University of Kentucky Entomology, Bed bugs. http://www.uky.edu/Ag/Entomology/entfacts/struct/ef636.htm