Although they were thought to have been eradicated long ago, bed bugs are a growing problem in our latitudes. Reasons for this lie not only in tourism and global trade, but above all in increasing resistance to insecticides, which favor bed bug infestations. If one notices bedbug bites on oneself, the disgust is usually great. Inevitably, one then wonders whether bed bugs are dangerous to humans and what one can do against the pests. We answer these and other questions in the following article.
What do bed bugs look like?
The bed bug – also known as Cimex lectularius – is found all over the world. The blood-sucking parasite is active all year round, mostly in inhabited indoor spaces. Its preferred host is humans, but much less frequently it preys on pets, birds or even bats. The bed bug belongs to the family of flat bugs. Depending on whether it has just finished a blood meal, the adult bed bug reaches a size of between four and nine millimeters. The six-legged, wingless parasite is hairy, reddish-brown in color and has a flat body shape. By the way, it owes its colloquial name to this – wallpaper flounder. Bed bugs before and after blood meal – iStock.com/JasonOndreicka and iStock.com/smuay
A bed bug infestation is often noticed late in the process
Basically, the bed bug can be easily recognized by its typical appearance. During the day, however, the nocturnal co-inhabitants are hardly visible. In accumulations, they then hide in the cracks of the slatted frame, the folds of the mattress, behind baseboards, heating pipes, light switches or even under wallpaper. At night, the little bloodsuckers are attracted by the warmth, smell and breath of their host and leave their hiding places. An infestation is relatively protracted. This is not least because signs – such as bed bug bites – are not noticed immediately. In addition, bed bugs reproduce relatively quickly. A female lays about 150 to 200 eggs during her lifetime. In addition, the parasites are extremely hardy, as they can survive for several months without any food at all. By the way, bed bugs usually stay close to the sleeping place of their host. Only in the case of very severe bed bug infestations does a spread to other rooms or adjacent apartments occur.
Where do bed bugs come from?
In fact, a bed bug infestation has nothing to do with poor hygiene, although it is usually detected more quickly in a clean household. As a rule, you drag the parasites into your own four walls, the reproduction then occurs rapidly. Although the bedbug was thought to have been eradicated in Europe after the Second World War, it is now relatively common again. The reasons for this are to be seen in globalization, among other things: Thriving tourism, increasing migration as well as increased (second-hand) trade blur national borders and lead to bed bugs increasingly appearing in Europe. However, the main reason is clearly the increasing resistance of the pests to insecticides. There are many ways in which the bed bug enters inhabited interiors. It is often transported in luggage as an unwelcome souvenir, completely unnoticed. A single fertilized female in suitcase or travel bag is sufficient to trigger a massive bed bug infestation. Likewise, overnight guests can introduce the parasite. It is also not uncommon for the purchase of used furniture, picture frames, clothing or accessories to result in an infestation of the bed bug. More rarely, bed bugs migrate from bird nests located on the house to inhabited rooms. In cases of very heavy infestation, spread to adjacent homes is also possible. However, the bed bug is not usually transmitted from person to person. This is because the parasite only settles on its host at night and for the duration of feeding.
How can you tell if you have bed bugs?
Bites from bed bugs, which often show up in the form of a typical rash, are considered the first sign of the presence of the unwelcome roommate. In fact, while bed bug bites provide a clue, they are not necessarily a sure sign of infestation. This is due to the fact that bed bug bites are quite similar to those of other parasites – such as flea bites or mosquito bites. Even dermatologists cannot diagnose bedbug bites beyond doubt.However, in addition to bite marks, there are a number of other signs that may indicate or confirm a bed bug infestation:
- Traces of feces on the mattress, bedding, slatted frame or even wallpaper (small, black spots).
- Small traces of blood on night or bed linen
- Sighting of adult animals (alive or dead)
- Sighting of larval shells (nymph skins).
- Smell of bitter almonds (in case of very heavy infestation).
Detect bed bug bites
Recognizing bed bug bites is not that easy. For example, mosquito bites or flea bites do not have too much difference in appearance. Therefore, clues to a bed bug infestation are the time of year the bites occur on the one hand, and the absence of pets on the other. Bed bugs bite all year round, while mosquitoes are only active in the summer. In addition, flea infestation without pets is relatively unlikely. In addition, there are other criteria to distinguish bed bug bites from flea bites or mosquito bites. For example, bed bug bites are not noticed immediately. This is because the parasite releases an anesthetic secretion in order to be able to drink the blood undisturbed. Only some time after the bite, unpleasant symptoms become noticeable – and even that not always. Bed bug bites often look like a rash. They occur in rows, because bed bugs bite several times. This typical course of bites is also called bedbug street. In addition, redness, wheals and slight itching are often noticeable. Flea bites are usually detected much faster in comparison. They are usually more itchy and lead to clear skin thickening (papules). Bed bugs: Pictures of the bites – iStock.com/Joel Carillet
Are bed bugs dangerous to humans?
Bed bug bites are not only annoying, affected people often fearfully wonder what diseases bed bugs can transmit. Here, however, can be given the all-clear: So far, namely, no case is known in which the parasite would have actually caused diseases. Thus, the bite of the bed bug may well be unpleasant, but it is not dangerous in the strict sense.
Treat bites from bed bugs – what helps?
In many people, however, the bite of the bed bug leads to slight redness, wheals as well as an unpleasant itch. Increased scratching increases the risk of bacterial infection. Allergic reactions to the secretion secreted by the bedbug when biting are also possible. This can lead to significant swelling, increased wheal formation and severe itching. In such cases, it is advisable to consult a dermatologist. Over-the-counter creams or – in the case of more severe symptoms – cortisone ointments can be used to treat bites and quickly relieve unpleasant symptoms.
Psychological consequences of a bed bug infestation
The psychological stress associated with a bed bug infestation should not be underestimated. Affected people often develop strong fears or feelings of disgust. They feel at the mercy of their own four walls and extremely uncomfortable. Conspicuous features such as compulsive washing or social isolation can also be observed.
What can be done against bed bugs?
To get rid of the annoying bed bugs as soon as possible – that is the pressing wish when one detects an infestation. In fact, however, those affected should better not fight the pests on their own, even if over-the-counter remedies against bed bugs suggest that this is quite easy. In fact, the opposite is true. Fighting bed bugs can be extremely tedious and requires the expertise of professionals. In addition, commercially available sprays against bed bugs are usually not very effective. In the worst case, they endanger your own health. Moreover, a single application does not usually stop the infestation, since bed bug eggs are resistant to insecticides. To actually permanently eliminate all developmental stages and contain the infestation, several coordinated treatments are necessary. In the event of a suspected bed bug infestation, the pest controller is therefore called upon – and as quickly as possible. He or she will determine whether an infestation is actually present and get to the bottom of the source. Contact insecticides with a long-term effect are generally used to combat bed bugs. Primarily, these are active substances from the group of pyrethoids, carbamates or pyrroles, which can also be used in combination.
What else helps?
In addition, supportive measures are necessary to get rid of bed bugs. For example, items that cannot be treated with an insecticide must either be stored well wrapped in the freezer at a minimum of -18 degrees Celsius for three days, or washed in the washing machine at 60 degrees with the longest program. Alternatively, they can be placed in an oven or sauna for about an hour at a minimum of 55 degrees. Eggs, larvae as well as adult bed bugs are effectively killed in this way. In addition, if you have a bed bug infestation, it is advisable not to use pieces of furniture and utensils in different rooms. Otherwise, the infestation can easily spread to other living spaces.
How long does it take for bed bugs to be gone?
Unfortunately, a bed bug infestation usually cannot be eliminated with a one-time treatment. Usually, several visits by the exterminator at intervals of about two to four weeks are necessary to really successfully combat all bedbug stages. Depending on the severity of the infestation, this can take several weeks to months. This is because the eggs do not respond to common insecticides. Therefore, long-term effective agents against bed bugs are usually used. This increases the likelihood that even freshly hatched larvae will die. In addition, existing resistance to insecticides is a growing problem in bed bug control. Thus, it may well be that some experimentation is required with regard to the active ingredient. The agents used are generally harmless to humans and vertebrates. In rare cases, however, allergic reactions may occur.
What exactly does the exterminator do against bed bugs?
The fight against bed bugs is relatively complex. As a rule, the exterminator must expose as many hiding places of the parasite as possible before the spray treatment. To do this, furniture is moved away or disassembled and all baseboards and light switches are removed. The insecticide is then sprayed into cracks and crevices and spread over open areas. Visible bed bug eggs must be removed either with tape or with a vacuum cleaner. The exterminator now inspects the infested rooms at intervals of about two to four weeks. As long as eggs, larvae or adult bed bugs can be detected, the treatment is repeated. Alternatively, insecticide-free heat treatments are also possible. In this case, special ovens (400 volts) are set up for about 36 hours. The temperature in the infested rooms is raised to 55 to 60 degrees Celsius. However, such treatments are comparatively expensive, unlike chemical treatments. They also do not necessarily drive away the bed bug reliably.
Prevent bed bugs – here’s how!
To prevent bed bug infestation in the first place, there are a few things to keep in mind, especially when traveling and buying second-hand goods:
- Always search vacation accommodations such as hotels and vacation homes for traces of the bed bug. If you find, ask for another room.
- When traveling, it is best to deposit your luggage well locked as far away from the bed as possible.
- After the vacation, it is recommended to unpack suitcase or travel bag in the bath or shower. In this way, stowaways are detected more easily.
- If you buy used furniture, clothing or accessories, you should scan them thoroughly for traces of the bed bug. Clothing is best washed at 60 degrees in the longest wash program. Alternatively, eggs, larvae and adults also die in cold (at least -18 degrees) or heat (at least 55 degrees).
Sources and further information
- Kuhn, C., Vander Pan, A. / Federal Environment Agency (2017): Guidebook. Bed bugs: Recognize, prevent, combat.
- Online information of the German Pest Control Association e. V.: Bed bug. Cimex lectularius. (Retrieved: 07/2020)
- Rahlenbeck, S. et al. (2015): Cimicosis: bed bugs – on the rise worldwide. In: Deutsches Ärzteblatt, Vol. 112(19).
- NDR (2019: Bed bugs – dangerous vacation souvenirs. (Retrieved: 07/2020)
