Generality
Blatte is the generic name used to indicate numerous species of insects belonging to the Blattodea order.
Also known with the common name of " cockroaches ", there are 4, 600 different species of cockroaches currently known and divided into six different families.
These are insects widespread almost all over the world and at any altitude (some species are present in places that are even over 2, 000 meters above sea level).
Cockroaches - which normally give rise to feelings of disgust and annoyance - should not worry so much about their appearance, but about the possible allergic reactions that they are able to trigger and the potential pathogens they are able to transmit to humans, giving origin to very serious diseases.
Fortunately, with the help of a few simple measures, the risk of "invasion" by these insects as well as the risk of contracting pathologies are rather reduced. In the unfortunate eventuality of infestation by cockroaches, on the other hand, it could be necessary to resort to drastic measures, such as insecticides or actual disinfestations by specialized firms.
What are
What are the cockroaches?
As mentioned, cockroaches are insects of the Blattodea order which belong to six different families: Blaberidae, Blattellidae, Blattidae, Cryptocercidae, Polyphagidae and Nocticolidae. Within these families are included more than 4, 000 different species of cockroaches that can live almost anywhere. Of these thousands of species at the moment, there seem to be only 30 that can interact and create problems for humans.
Species of Common Cockroaches in Italy
In Italy, there are mainly cockroaches belonging to three of the aforementioned families: Blattellidae, Blattidae and Polyphagidae. The most widespread species on the Belpaese surface, however, belong mostly to the Blattidae family and are:
- Blatta orientalis, also known with the common names of oriental cockroach, black or common; undoubtedly better known as a common cockroach.
- Blattella germanica, also known as gray cockroach.
- American Periplaneta, commonly known as red cockroach or American cockroach.
- Supella longipalpa, known by the vulgar name of the furniture cockroach or brown banded cockroach.
Did you know that ...
In some cultures - like the Chinese, Thai and Mexican - cockroaches are part of the normal diet. In Mexico and Thailand the bodies of cockroaches are cooked by boiling or grilling, or they are dried. In China, on the other hand, cockroaches are mostly eaten fried. Of course, insects intended for human consumption are not caught in the wild due to the potential transmission of pathogens, but are bred.
Features
Main Morphological Characteristics of the Cockroaches
Naturally, each species of cockroaches has its own peculiarities and characteristics. However, in principle, it is possible to state that cockroaches are insects with a body that can be more or less elongated, characterized by generally not too showy colors ranging from light brown to black. The dimensions are extremely variable: from tiny cockroaches just 3 millimeters long, you get to decidedly larger cockroaches that exceed 8-9 centimeters in length.
The head has variable-sized antennas, the mouthparts are chewers and the jaws are generally short but strong. The legs are thin but functional; depending on the species, cockroaches may have more or less developed wings even if, in some cases, they are absent.
Interactions with Man
Cockroach behavior and human relations
Most cockroaches show phytophagous behavior, that is, they eat plants and plants of different types. Many species, however, are omnivorous and can also eat food for human and / or animal nutrition. Generally, it is precisely the presence of food - in particular, sugary and starchy foods - that drives the cockroaches to infest foodstuffs, public places and domestic environments. The interactions that these insects have with humans, therefore, concern the infestation of residential areas, pantries, warehouses, etc.
Cockroaches are insects that love dark and damp places, while they fear the light and this is why they tend to appear in houses only at night, running away and seeking shelter in holes and cracks as soon as the light is turned on or during daylight hours.
Curiosity
Some cockroaches also practice predation on other insects. In this regard, it has been noted that the American cockroach can feed on bed bugs (extremely annoying ectoparasites).
Damage
Damage caused to humans by cockroaches
Due to the interaction (generally indirect) of cockroaches with humans, these insects can give rise to various problems, causing damage, sometimes very serious. In detail, cockroaches can cause:
- Economic damages deriving from the infestation of foodstuffs that can no longer be marketed following contact with these insects, or economic damages deriving from the attack on crops and plants due to the phytophagous nature of cockroaches.
- Health damage due to:
- Potential transmission of pathogens of different nature: bacteria, viruses, fungi, protozoa and helminths.
- Induction of allergic manifestations in sensitive individuals.
With regard to the first point, it should be pointed out that the economic damages caused by the eating habits of cockroaches are not so relevant. Undoubtedly they involve a waste of material and money, but the economic damages induced by them are generally contained and not excessively relevant.
On the contrary, damage to health caused by the presence of cockroaches in foodstuffs, in public places and / or inside homes can be decidedly more relevant. In this regard, it should be pointed out that cockroaches can transmit pathogens or allergenic substances by direct contact with foods or objects of common use, or through their feces or their regurgitations. Blatta-man direct contact, on the other hand, is extremely rare, as these insects tend to escape when a human being approaches.
Cockroaches and Myths to Dispel
Around the cockroaches - considered unpleasant by most western cultures - revolve various myths and legends completely without foundation. Below, the main ones will be debunked:
- Cockroaches can bite or sting humans : it is a widespread belief, but not entirely true . In fact, cockroaches are not able to sting humans because they do not have any sting and - although they are equipped with a chewing apparatus - they usually do not bite humans. As stated above, in fact, these insects have a very shy behavior and in the presence of human beings they tend to run away and hide. Therefore, the potential transmission of pathogens and the onset of allergies is hardly due to an unlikely attack on the insect.
- Cockroaches live only in dirty places and with a poor degree of hygiene : it is the most widespread commonplace regarding these insects; as common and widespread as false . While it is true that cockroaches can easily live in unhealthy places and with reduced hygienic conditions, it is also true that they can infest clean and sanitized places just as easily. In fact, cockroaches are cosmopolitan insects that can adapt to life in different environments, as long as there are the conditions to ensure their survival, such as the presence of food and hiding places. Therefore the simple fact of not physically seeing these insects in an impeccably clean house does not mean that they are not present. In fact, as stated above, cockroaches prefer to come out in the darkest hours and, above all, when there are no human beings nearby.
Transmitted pathogens
Pathogens and diseases transmitted by cockroaches
Cockroaches are able to convey different types of pathogens (bacteria, viruses, fungi, helminths and protozoa), in turn, capable of giving rise to dangerous infectious diseases in humans.
As stated, transmission does not occur by direct contact between cockroaches and humans. These insects, in fact, behave as mechanical vectors of the aforementioned pathogens and the transmission to humans occurs through the ingestion of food or the use of tools with which the cockroaches have been in contact.
In turn, the insect may have come into contact with the pathogen in poorly hygienic, unhealthy and unclean environments where infected substances or objects are present (including animal excrement or sick human beings).
Particularly widespread is the transmission of bacteria (including, but not exclusively, staphylococci, streptococci and clostridia), as is the transmission of viruses (among which we find, for example, that of hepatitis A).
However, among the diseases that can be easily transmitted through cockroaches, we recall:
- Salmonellosis : infection triggered by Gram-negative bacteria belonging to the genus Salmonella . In milder cases the infection causes gastroenteritis, while in more severe cases it can give rise to septicemia and extraintestinal manifestations.
- Tuberculosis : it is an infectious disease that particularly affects the lungs and is caused by an infection supported by Mycobacterium tubercolosis, better known as Koch's bacillus.
- Hepatitis : it is an inflammation of the liver that can be triggered by infections sustained by microorganisms of various types, both viruses and bacteria (infectious hepatitis).
- Typhus : this is a systemic infectious disease triggered by the bacterium Salmonella typhi . In order to ensure rapid healing, typhoid should be promptly diagnosed and treated.
- Cholera : is an infectious disease caused by the exotoxins of Vibrio cholerae, a Gram-negative bacterium belonging to the vibrio group. Infection can occur in a particularly severe form and timely treatment is essential.
Allergies
Allergic manifestations induced by cockroaches
The role of cockroaches in the onset of allergic disorders - and, in particular, of respiratory allergies - has taken on considerable significance only in relatively recent times. In this case, cockroaches do not represent the mechanical carrier of any allergenic agents, but they are the same cause of allergies. More specifically, several allergens from saliva, faeces and the body of the same cockroaches were isolated and identified.
These allergens - re-traceable in the dust of many homes and public places - are capable of giving rise to bronchial hyper-reactivity and asthmatic attacks in predisposed subjects.
Did you know that ...
Recent studies have shown that the continuous contact of children with high concentrations of cockroach allergens can increase the risk of asthma.
In addition to this, the existence of a cross-allergy between cockroaches of different species and even a cross-allergy between cockroach allergens and those resulting from dust mites has been demonstrated.
However, the possibility of experiencing allergic reactions following contact with allergens originating from cockroaches - in addition to the genetic predisposition of each individual - depends on various factors, such as:
- The species of cockroach from which the allergens originate;
- The concentration of these allergens in the home, workplace, etc .;
- The duration of exposure to allergens (spending a lot of time in places where there are allergens resulting from cockroaches, in fact, increases the risk of experiencing allergic reactions);
- The presence of more or less accentuated ventilation. In ventilated places, in fact, allergens released by cockroaches circulate more easily, which increases the likelihood that they can favor the appearance of allergic manifestations.
Fight against the cockroaches
Useful Tips for Avoiding Cockroach Infestations
Although cockroaches can be eliminated by various types of insecticides, prevention is the best weapon to combat them.
It is true that these annoying insects can also live in carefully cleaned places, but proper hygiene and above all adequate food preservation represent in any case the first step to avoid the arrival and allocation of cockroaches in homes or other places. In fact, despite the careful cleaning of the environment, if cockroaches can find easy access to food, they will infest even the cleanest homes or rooms.
In any case, to avoid any cockroach infestation it is necessary to try to reduce the possible sources that can favor the development of this phenomenon. More in detail, it can be useful:
- Avoid leaving cockroaches, or any other insect, food or leftovers within reach.
- Keep food properly closed and in a dry place.
- Regularly clean the places where food is stored, washed, prepared and cooked (larders, kitchens, stoves, pots, crockery, cutlery and places where these objects are stored, storage warehouses, etc.).
- Store waste - in particular organic waste - in a place that is not accessible to cockroaches, taking care to maintain a good level of hygiene also in this area (cockroaches, in fact, also love to eat food scraps and not just food kept in a pantry, in storage warehouses or in the kitchens of restaurants).
- If necessary, use appropriate traps or insecticides in the home or in the places at risk to nip a possible invasion of cockroaches in the bud.
If this does not prove to be functional and if you are faced with a real cockroach infestation, you may need to contact specialized disinfestation companies.
