Recognition of Bedbugs
Bedbugs (Cimex lectularius) are haematophagous parasites of man, that is, a bit like mosquitoes, they feed on human blood by biting people.
The bed bugs are more or less oval shaped and their dimensions are the following: the male 4.0-6.5 mm x 2.2-3.2 mm; the female 4.5-8.5 mm x 2.7-3.7 mm. Swollen with blood, they can reach 9 mm in length as they stretch the segments of the abdomen.
They are very flattened, of reddish-brown colour, even if the immature forms may have softer colours up to the pearly white. It is not always easy to spot bedbugs in a room, as these insects have nocturnal habits and sting only at night, moving from their hiding places towards the unlucky sleeping guest.
Also their stings often go unnoticed, at least at the beginning, and are confused with injuries due to other causes or to other insects such as mosquitoes to which we are by sure more accustomed. Cimex lectularius, the common bedbug, is a parasite hosted almost exclusively by man.
If man is not present, bed bugs also suck the blood of animals, mainly birds and bats. Each female fertilised with bedbugs can lay up to 500 eggs during her lifetime, but she lays five to twelve eggs a day, which hatch in between 6 and 20 days.
Each male can fertilize several females. During the time span of one year, the bugs may reach the reproduction for 4 generations. The eggs are pearly white, about 1-1,5 mm long, and are laid (glued), isolated or in groups, close to the nesting points and, in any case, in hidden positions and difficult to reach. They are practically waterproof and, therefore, resistant to the effect of the common insecticides.
Small pale coloured neanids come out from the eggs, already ready to nourish of blood. The adult stage, in favourable conditions, is reached within 30-40 days, after five moults. Each moult requires at least one meal of blood. The adults live, as an average, 4-6 months, but in particular conditions they can reach the two years.
Signs of presence of bedbugs
Because of their ability to stay hidden, locating bedbugs is not always easy or simple. However, their presence can be detected quite easily by searching for “signs” of infestation, which are characteristic and usually quite evident.
One of the most typical signs of the presence of bedbugs is the excrement that these insects produce, which are usually deposited near nesting points in the form of small round, slightly raised spots with a diameter of 0.3-1 mm. The faecal stains have a “tarry” appearance and, if treated with hydrogen peroxide, tend to produce oxygen bubbles by reaction with the iron atoms present in the degradation products of the haemoglobin of the blood.
Fragmented with the classic faecal stains, it is possible to find other yellowish white and “dry” looking stains: these are small accumulations of uric acid salts emitted by the excretory apparatus. Since insects tend to get rid of the last residues of the previous meal immediately after the new blood meal, faecal stains can often also be found on sheets, blankets or on the skin itself of the spotted individual.
During its development cycle Cimex lectularius goes through 5 growth stages to reach the adult stage.
The transition from one stage to the next takes place through a moult, during which the insect gets rid of its old cuticle, which is then abandoned in the environment. These fragile remains (exuvie), which have typical appearance and colouration, are often easier to detect than the living specimens, and are in any case an unequivocal sign of the presence of the insect.
Since many other insects leave their remains in the environment, all of which can be similar to an untrained eye, it would be good if the final identification were carried out by a competent person. In the case of an ongoing infestation, it will also be possible to detect the presence of eggs, sometimes very numerous, within the nesting points and/or in the immediate vicinity. Being white or in any case very light, the eggs are very easy to see, especially on dark surfaces, where, on the contrary, faecal stains are often less evident.
In the absence of other characteristic evidence, the presence of stings and the resulting allergic reaction is not in itself an indication of bedbugs. In fact, there are many other species of arthropods that can sting humans habitually or occasionally, or in one way or another cause allergic reactions that are difficult to distinguish from those caused by bedbugs.
The bedbug stings when they occur are not painful so that the affected person notices the stings when waking up or after several hours. The most affected areas of the body are the limbs and back. Usually the stings are concentrated in certain areas of the body and can be distributed fairly aligned with each other as they reflect the trajectory that the bedbug travels along moving over the body of its host and stinging him.
Similarly to the previous case, in the absence of other symptoms, the appearance of some bloodstains on pillows or sheets is not automatically a sign of bedbugs. The stains can be produced by some minor skin lesions, loss of a crust, acne and other factors. On the other hand, the constant and continuous appearance of very small blood stains should not be overlooked and should be considered a possible wake-up call.
Cimex lectularius is a species now widespread throughout the world and especially in the temperate climate zones of North America, Europe and Central Asia.
Temporary reception activities, such as hotels, hostels, farmhouses, B&B, campsites, etc..
All those means of transport where passengers spend their time sleeping, or in any case remaining practically immobile, in a lack of light, for example trains, ferries and ships.
However, the problem can also concern different means of transport such as buses, subways, trucks and vans (if used to transport infested materials), but also campers, caravans and caravans (especially if rented).
Cinemas and theatres, where spectators sit for quite a long time in the dark and with their attention focused on the show.
Any other context in which there are human beings sleeping (private homes, timeshare, residences, rented holiday homes, boarding schools, student dormitories, communities, hospitals, prisons, etc.).
It is important to stress that the presence of bedbugs is not necessarily linked to poor hygienic conditions, as these pests are able to live very well in very clean environments as well as in poorly clean environments.
Obviously, however, disorder and poor hygiene can increase the chances for bedbugs to find hiding places and be intercepted within an environment.
How do bedbugs get there?
The appearance of a Cimex lectulariusin infestation in a new environment is always a consequence of the accidental introduction of specimens from another already infested environment.
Bedbugs spread from one environment to another in two different ways:
- Over very short distances the spread is active and it is the bedbugs themselves, as the infestation proceeds, that spontaneously colonize new surrounding areas. From one room to the adjoining rooms, from one apartment to the adjacent ones, etc.
- The other mode of diffusion, much more insidious and common, is the passive one: the bugs are unconsciously transported from one environment to another as “unwanted passengers”, hidden inside clothes, luggage or other objects and, in this way, they can move hundreds or thousands of kilometers in a few hours.
- Once penetrated into an environment, bugs tend to quickly locate possible “hot spots”, i.e. more favorable locations to nest in close proximity to guests’ rest or resting places.
Most infestations usually develop on a bed frame or in the immediate vicinity, usually within a radius of one and a half metres from the point where the head rests on the pillow to sleep.
As the colony grows larger, areas further and further away from the starting point will be infested and, as time goes by (thanks also to passive transport phenomena) their presence will also affect other adjacent and non-adjacent rooms.
If a bug infestation is not identified and eradicated in a short time, it tends to develop exponentially within a few weeks, always involving new environments, especially if there are people on which the bugs can feed.
Health risks from bedbugs
The direct damage caused by the bugs is the allergic reaction triggered by the stings. Except in rare cases of hypersensitive subjects, where the reaction can also be very violent (breathing difficulties, anaphylactic shock), the symptoms are usually local and, apart from the discomfort and itching, do not pose any real danger to the victim. To date, bedbugs do not appear to be able to transmit diseases.
However, the psychological damage caused by bedbug infestation should not be overlooked. This is probably due to the fact that bedbugs tend to infest precisely those environments where humans feel safer and more protected, and their attacks usually occur while the host is asleep and particularly helpless.
The fact of having to live forcibly with a blood-feeding parasite, preferably hiding in bedrooms and attacking while sleeping is more than enough to seriously compromise anyone’s mental serenity. All this can result in states of anxiety, panic attacks, depression, insomnia, exhaustion and so on.
Prevention of bedbug infestations
Prevention aims more to prevent the parasite from entering a new environment through objects or people who passively carry the parasite from one place to another. If you therefore suspect that you are in or have frequented a place at risk, this is always appropriate:
- Do not move objects from premises where the infestation is in progress, unless they have to be removed or cleared.
- Objects to be disposed of (magazines, paper, rubbish bags) should be closed in intact and sealed plastic bags.
- Sheets, curtains and linen taken from infested premises shall be kept closed in plastic bags during cleaning and transport for washing and shall be washed at a temperature of at least 50°C.
- Keep control of objects/personnel entering and leaving the rooms even after pest control treatments (the risk of transport to/from adjacent untreated rooms should always be kept in mind).
- Check and inspect your luggage and its contents with care if you suspect that you have stayed in a bedbug infested environment.
Problems related to reception and transport activities
The type of environments frequented by bedbugs has serious consequences for such activities.
In the meantime, the possible economic damages must be considered: they include the expenses for the disinfestation interventions, the costs for the reclamation of furniture and clothing but also, in the case of the reception activities, the loss of income deriving from the impossibility to use the infested rooms.
There is also a not insignificant damage to image: the reporting of a bedbug infestation can seriously damage the commercial image of an activity, and the fact is even more serious if the activity in question is part of a chain of similar activities or under the same trademark.
Bedbug control systems
For an effective fight, all bedbug hideouts must be found. The search must also include double ceilings, raised floors and adjacent rooms.