BUGS

From Big Medical Encyclopedia

BUGS (Hemiptera) — group of a class of insects. The St. 20 thousand types is known To., leading a land or water life. One types eat juice of plants, others — blood of animals and the person, the third are the predators destroying insects, ticks (bugs-hishchnetsy) and even whitebaits of fishes (many water To., especially bugs laserworts). Among herbivorous To. are reckoned, the pages doing considerable harm - x. to cultures. Blood-sicking To. some types are poisonous insects, and and carriers (see) activators of a number of diseases. The secret of sialadens allocated To has poisonous action. at the act of a krovososaniye.

To. — insects with hemimetaboly. Their life cycle consists of the following phases: egg, larvae of 5 stages of development and adult individuals (imago). The greatest practical interest to medicine is of To. two families: Cimicidae and Triatomidae — brownies (nested norovye) the trapping parasites attacking the person. To. all types of these families are obligate bloodsuckers at whom both larvae of all stages of development and adult individuals eat blood.

Typical representatives this. Cimicidae: a bug bed (Cimex lectularius), a bug bed tropical (S. rotundatus), a bug of bats (S. pipistrelli), Lastochkin a bug (Oeciacus hirundinis) sometimes getting into the dwelling of the person, etc. Bugs this. Triatomidae are widespread almost only in the tropical and subtropical districts of America. It is known apprx. 100 types and these subspecies To., from which third are carriers American trypanosomiasis (see), or Chagas diseases (see. Shagasa disease ). From them main types are Rhodnius prolixus, Triatoma infestans, Panstrongylus megistus. Often triatomovy K. consider also as a subfamily of Triatominae of more extensive and everywhere widespread family of bugs-hishchnetsov (Reduviidae), also such types as Reduvius personatus parasitizing hl belong to Krom. obr. on nesekomy (including and on bed To.), and Phonergastes bicolori pes destroying ticks of Ornithodorus moubata — carriers of spirochetes of a typhinia. These types can attack also the person.

Fig. 1. Cimex lectularius — a bed bug (a female — full size of 5 — 6 mm).

Bed bugs — small wingless insects of red-brown color, length apprx. 6 and width apprx. 3 mm (fig. 1). The body is strongly flattened that allows To. to get into narrow cracks. Bed To. live in furniture, cracks and cracks of walls, a floor and a ceiling, holes and nests of synanthropic rodents and birds, in vivariums; their presence can be established on excrement in the form of black-brown spots. One female lays several honeycombs of eggs for the life. Duration of development from egg to an imago makes from 1 to 2,5 month and depends on air temperature and timeliness of food. Low temperatures do not kill To., and at t ° — 21 ° there comes the okocheneniye.

Bed To. are, as a rule, active at night; in questings they can creep on quite long distances. Bite To. generally open body parts, often piercing skin several times in search of the suitable place, also drink from 0,5 (larvae of the 1st stage) to 7 mkl blood (imago). To. are capable to long starvation (about one year), especially at low temperatures. At optimal conditions adults To. can live up to 14 months.

Stings To., often cause an itch, blistering and having combed; at mass reproduction bed To. cause disturbance to people, deprive of them a normal dream and rest. Reliable data about transfer bed To. there are no transmissible diseases though it is known that To. can keep in themselves causative agents of plague, sypny and a typhinia, the Q fever, a tularemia, etc.

Fight with bed To. consists of preventive and destructive actions. Preventive actions are directed to the prevention of emergence and reproduction To.; they include systematic repair of rooms, seal of cracks and plastering of walls, ceilings, updating and subbonding of wall-paper, systematic cleaning of rooms, obligatory disinsection of furniture, the mattresses and other things transported to new apartments from old, infected To. Different types physical belong to destructive actions. and chemical means of fight: a burning of metal beds, brick and cob walls fire of a blowtorch, processing of wooden products boiled water or a hot steam, cleaning of upholstered furniture and carpets by beating or by means of vacuum cleaners. From chemical means of fight with To. drugs GHTsG, a hlorofosa, a metaphos, trichlorometafos-3, etc. are most common (see. Insecticides ).

Fig. 2. Rhodnius prolixus — a triatomovy bug (a female — full size of 20 — 25 mm).

Triatomovy bugs is much larger, than bed: length of a body is from 15 to 34 mm (fig. 2).

They are often brightly painted, their wings half hitinizirovana.

Triatomovye To., as well as bed To., lead a nocturnalism, attacking the sleeping animals or people, and their sting is painless and the sleeping person does not wake up from a sting. Bite often about eyes and in lips, from here their other name «potseluyny bugs». Stings are followed by a severe itch and hypostases, and at persons with hypersensitivity also rash on a body, the face edema, heartbeat, an asthma which is speeded up by pulse and even a loss of consciousness; repeated stings can cause stronger reaction. During mass attack triatomovy To. people suffer also from a loss of blood since the largest types exhaust at one time up to 4 Ml of blood.

Triatomovye K. participate in transfer of American trypanosomiasis (see). In intestines To. the trypanosomes which got there with blood of the patient turn into metacyclic forms which then are allocated with excrement K. Infection of the person comes at hit of trypanosomes on mucous membranes, in a wound from a sting or a raschesa.

Fight with triatomovy To. includes the same measures, as fight with bed To.



Bibliography: The multivolume guide to microbiology, clinic and epidemiology of infectious diseases, under the editorship of H. N. Zhukova-Verezhnikov, t. 9, page 777, M., 1968; Resistance to insecticides and fight against carriers, a Series tekhn. dokl. No. 443, page 295, Geneva, WHO, 1972; The Guide to medical entomology, under the editorship of V. P. Derbenyova-Ukhova, page 221, M., 1974.


V. N. Danilov.

Яндекс.Метрика