From Big Medical Encyclopedia

DERATIZATION (fr. deratisation) — destruction of the rodents constituting epidemiological danger or causing economic damage. Is usually carried out in inhabited and uninhabited constructions, in port constructions, by the ships, and also on the open area.

There are instructions that fight against rodents was conducted in Ancient Egypt. Rodents caused extensive damage to agriculture in this connection their natural enemies — cats were protected. In Ancient Greece and Rome, in addition to cats, for fight against rodents used caresses and ermines. Primitive tools of fishing of rodents (lovchy holes, samolova) began to be used already in the Middle Ages. Systematic deratization events are held since the beginning of 20 century.

Modern D. includes system of preventive and destructive actions.

Preventive actions

Preventive actions are directed to destruction of a food supply rodents (see) and creation of unfavorable conditions for their nesting and the hidden movement. In settlements preventive D. consists from a dignity. and construction and technical actions.

So, in rooms carry out daily cleaning, collect garbage only in metal tanks which timely take out. In warehouse and shops foodstuff stores in rodent-proof chests or on racks at the height of 25 — 30 cm from a floor.

Also the system of the stroitelnotekhnichesky actions interfering penetration of rodents into rooms is important. E.g., introduction openings of pipes and technical conductings close up cement, sheet iron, and air vents — the metal gauze with cells in 5 mm; windows of cellars shall be glazed; openings of refuse chutes close metal doors, etc.

Destructive actions

Destructive actions conduct departments and departments of preventive disinfection a dignity. - epid, and disinfection stations (see. Disinfection station , Sanitary and epidemiologic station ), and also veterinary service of the Ministry of Agriculture, disinfection services of other departments.

Destruction of rodents is carried out disinfectors (see) under the direction of dezinstruktor (see). Continuous systematic D.'s carrying out is the most effective, at a cut control of objects and deratization actions (in case of detection of rodents) are carried out at least once a month during the whole year.

Destructive events are held mechanical, chemical and biol, by methods (see. Dezinsitsiruyushchy means , Deratization means ).

A mechanical method — extermination of rodents by means of traps, traps or animal traps of various systems. Practices in settlements. Apply spring traps to catching of mice and rats (like Gero), and also arc traps.

For obtaining the greatest success it is necessary to accustom for 7 — 10 days rodents to tools of fishing for what in not alerted traps (traps) put a bait. Only after rodents will eat completely a bait, traps (traps) guard. This reception overcome the instinct of care which is especially strongly expressed at rats. Catching of rats can be made by means of traps or fish-traps — wire cells with a cone-shaped entrance.

Chemical methods — use of the poisoned baits, dusting of holes of rodents ratitsidam (see), a zatravlivaniye of rodents in holes gaseous toxic agents.

The poisoned bait (priming) is prepared from the foodstuff, attractive to rodents, mixed with toxic agent (ratitsidy). Use of long-term points of poisoning — boxes, trays and other devices is effective. Before use of a bait it is necessary to establish whether her rodents eat. Sizes of primanochny boxes: length is 30 — 40 cm, width is 15 — 18 cm, height is 15 — 18 cm. Two walls of a box deafs, and in two adjacent are made round openings that provides a free admission of rodents in a box and escaping it. Edges of a cover from walls with openings go beyond edges of walls on 5 cm. The cover is closed on the lock. The box is established in a corner of the room so that its walls with openings were turned to walls of the room. The interval between a box and walls of the room provides to rodents free access in a box, and for children and domestic animals the bait remains unavailable. Usually in boxes put the baits containing 100 g of flour, 10 g of sugar and 5 g of a ratitsid — zoocoumarin, a ratindan, etc. Long-term points of poisoning place at the rate of 1 — 2 by 100 m 2 areas. Apply also grain and grain bait containing phosphide of zinc or krysid. Dusting of holes and tracks of rodents is made anticoagulants. Along walls fill dust platforms 5 wide — cm and 15 — 30 cm long (10 — 15 g of drug).

Holes dust by means of hand sprayers. On some objects (grain, flour warehouses, bakeries) it is possible to apply drinking bowls with the water containing 10% of sugar and pollinated by zoocoumarin. — carriers of causative agents of diseases — apply the baits containing drugs of both ratitsidny, and insecticidal action (system poisons) to simultaneous extermination of rodents and their ectoparasites. Drug of insecticidal action, getting into blood of a little wild beast, causes death of the insects parasitizing on it and ticks; carry out processing of holes by mix of powdery ratitsid and insecticides or create long-term points of poisoning with the poisoned baits containing ratitsid and an insecticide.

If the square freed from rodents makes 80% and more, D.'s results are considered as satisfactory. The accounting of efficiency of D. is carried out, placing traps before destructive works (one trap on 33 m 2 the inspected area). Catching of rodents is carried out within 5 days. The percent of the got mice and rats on 100 traps is calculated. The accounting of efficiency of D. is carried out also by comparison of data on visit by rodents of dust platforms from powdery anticoagulants prior to the beginning of and after carrying out.

Biological methods — use of natural enemies of rodents, and also specific microorganisms, safe for people and domestic animals. In city conditions restriction of number of mice and rats is promoted by cats and dogs.

Bakteriol, method of controlling with rodents is based on use of the baits containing bacteria, pathogenic for rodents, from group of salmonellas (see. Deratization means , biological means, Salmonella ).

Accident prevention. During the work with toxic chemicals and bacterial cultures safety regulationss are strictly followed. Preparation of the poisoned baits is made in the special rooms provided to artificial ventilation (see).

The working personnel shall have overalls (a dressing gown, rubber gloves) and a respirator (see. Respirators ). The baits containing bacteria are forbidden to be applied on food objects, in food warehouses, in nurseries and to lay down. institutions.

Fight against rodents in field conditions

in the territory of the USSR field D. is carried out against the rodents bringing economic damage on fields and in forest plantings and also on epid, to indications in the natural centers of infectious diseases, napr, in the centers of plague (deserts, semi-deserts, stony steppes), a hemorrhagic nephrosonephritis (timberland), etc. Observance of rules of an agrotechnology, in particular timely bevelling of grain crops and their thrashing without loss, fight against weeds on crops, near them, etc. is essential for restriction of number of rodents on fields. On the timberland for the prevention of percentage by weight of forest rodents (red voles, forest mice, etc.) timely clearing of cutting areas, reduction of terms of export of business wood, combustion of brushwood, creation of the cleared-away woods of park type, especially in a green zone of the city are necessary.

In the natural centers of plague the greatest epidemiol, gophers, groundhogs, big, redtailed and midday sandworts matter. Apply preferential chemical method of controlling by means of the grain poisoned baits to fight against them. As baits use oats, wheat, corn, etc. For 1 hectare of the territory it is spent apprx. 2 kg of a bait. As a ratitsid phosphide of zinc with addition of 1% of vegetable oil is widely applied. Replacement of this drug with less toxic, napr, glyfluor is reasonable to prevent death useful granivorous and birds of prey. Use of the grain poisoned baits containing anticoagulants practices (difenatsin, zoocoumarin). For fight against groundhogs use a gas method — a priming of holes tsianplavy, chloropicrin. In comparison with a primanochny method gas is more labor-consuming and unproductive. As on all species of groundhogs trade is conducted, their destruction is made strictly on epid, to indications. Field D. by means of grain baits practices preferential in the spring — in the period of deficit of seed forages. Sowing of the poisoned bait is made from the airplane or from the car, supplied with the special equipment. In mountain areas or during the processing of the limited area manual sowing of a bait which is made by group of workers under the direction of a dezinstruktor is possible.

The accounting of efficiency of D. is carried out on platforms of 25 x 25 in size where the number of inhabited holes and number of the caught rodents before holding destructive actions is counted.

In the natural centers of a hemorrhagic nephrosonephritis exterminate red voles, forest mice, etc., disseminating the grain poisoned bait containing phosphide of zinc and vegetable oil. Replacement of phosphide of zinc with glyfluor or zoocoumarin is possible. Apply also the baits containing ratitsid and an insecticide. Sowing of a bait is made from the airplane or a manual way. During the holding destructive actions it is impossible to allow sowing of the bait poisoned with phosphide of zinc in close proximity to settlements in order to avoid death of domestic animals. For these purposes instead of the poisoned bait it is possible to recommend the layout of the paraffin briquettes containing grain and ratitsid (e.g., glyfluor, low-toxic for birds). 2 — 3 kg of briquettes which place under shelters at distance 15 — 20 m from each other are spent for 1 hectare.

Natural enemies of rodents in field and forest areas are birds of prey (a buzzard, a common kestrel, a kite, different types of owls) and mammals (a marten, a polecat, an ermine, caress, etc.).

Deratization of vessels

Fight against rodents on sea vessels is obligatory and is regulated by «The international medical and sanitary rules» and «Rules on sanitary patrolling of the USSR from a drift and spread of quarantine and other infectious diseases».

On vessels apply preventive and destructive events which are held taking into account species composition of rodents, a dignity to fight against rodents. - tekhn. a state and specific conditions of various types of vessel depending on the operational mode (the parking in port or on raid, the parking on ship repair, preparation for an exit in flight, stay in flight, return after swimming etc.).

Preventive actions are directed to the maintenance of the vessel in due a dignity. a fortune, creation of the conditions interfering penetration of rodents on deprivation of their shelters and difficulty of access to food. Vessels equip with special protecting constructive devices. The prevention of transition of rodents to vessels is carried out by hanging on mooring special zagraditel in the form of antirat boards. Foodstuff and their waste store in densely closed container. It is forbidden to store food in inhabited and service premises. Brightly ladders are lit and rise by height of 1 m at night. Protecting screens move away from boards of the vessel upon termination of handling works.

Destruction of rodents on vessels is carried out by mechanical and chemical methods. Bakteriol, a method on vessels is not applied.

To catch of rats apply traps and fish-traps, and to catch of mice — spring presses and mousetraps.

Chemical deratization means on vessels apply in the form of the poisoned baits (briquettes, ship's biscuits, etc.). Of vessels apply to gas D. more often methyl bromide (see). In some cases use tsianplav and a cyclone. Though gas D. of vessels is the most effective method, carrying out it is accompanied by great difficulties, she demands difficult measures for the prevention of poisonings of members of crews of vessel and the personnel which are carrying out aeration. Therefore gas processing of vessels is carried out only in the presence of diseases of plague, detection of a case of rodents or their big number and after arrival of vessels from unsuccessful ports on plague and when it is not possible to destroy rodents by other methods.

Vessels are allowed to swimming only in the presence of «The certificate on deratization» or «The certificate on release from deratization». «Certificates on deratization» are granted a dignity. - epid, stations of ports after holding destructive actions. «Certificates on release from deratization» are issued to those vessels which are free from rodents that shall be confirmed with objective control methods (arrangement of presses, dust platforms).

Deratization in field conditions

precedes Deratization works carrying out the evils, and a dignity. - epid. investigations (see. Medical investigation ). It will be organized by army doctors, epidemiologists, zoologists. In the course of investigation the number, species composition, preferential areas and objects of settling, conditions favoring to reproduction of rodents is defined. Availability of warehouses of food and fodder and water sources to rodents, and also population them dugouts, blindages, tents, vegetation along roads, the forest strips and bushes adjacent to arable lands, ricks of straw and hay, stacks of bread, etc. comes to light. At the same time pay attention to features of a land relief, abundance of vegetation, quantity of forages and their availability to rodents.

In the winter field rodents take strictly limited habitals, napr, ricks, stacks, dwellings of the person, storage of food, etc.

For D.'s carrying out the order of command of parts allocates zoologo-deratization groups which number is defined by scales of the territory and volume of the forthcoming works. At considerable increase of number of rodents or emergence among them epizooty (see) Will organize and medics — epidemiologists and zoologists head. Before D.'s carrying out zoologo-deratization groups have theoretical and practical training.

Fight against rodents in field conditions includes protection (barrier) of objects against penetration in them of rodents and destructive actions.

For protection against rodents of tents, dugouts, food warehouses, the reservoirs used by troops (wells, tanks, etc.), during the Great Patriotic War ditches with lovchy holes, snow-ice walls were widely used. Not less important measure is storage of foodstuff, especially those which are not exposed further to heat treatment (bread, crackers, sugar), in a container, impenetrable for rodents: boxes, barrels with covers, racks on the columns equipped with cones from a tin or plywood. Fellings of wells supply with densely closed covers. Destruction of rodents in blindages, dugouts, in food warehouses and other objects includes use as standard mechanical means of fishing (mousetraps, traps), and various samolovka (a bucket-samolovki, the falling platforms) made of improvised materials. In tents, dugouts, blindages lovchy holes which dig out on corners of these constructions are applicable.

Chemical destructive measures consist in use of the poisoned baits or a gas method. Along with a priming of holes processing is carried out by insecticidal drugs them (see. Pesticides ).

Destructive events in the nature are held taking into account biol, features and specifics of habitals of rodents. The most general of them are the dyking of ricks, haystacks and straw ring ditches with lovchy holes which daily examine; in the winter — a construction of snow-ice walls. The old straw, chaff unsuitable for economic use, weeds burn.

In special and transport vehicles apply the poisoned baits placed in the perforated boxes warmed by cotton wool or rags to extermination of rodents.

Bibliography: Bashenina N. V., etc. Rodents are wreckers of gardens and kitchen gardens, M., 1961; In and sh to about in V. I. Disinfection, disinsection and deratization, M., 1956, bibliogr.; Vashkov V. I., etc. Fight against rodents in the cities and settlements of rural areas, M., 1974, bibliogr.; Lamurye V. B. The guide to ship sanitation, the lane with English, M., 1968, bibliogr.; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 32, p. 3, M., 1955; With in and r ides of e of N to about P. A. Mouse-like rodents and protection from them of a harvest, stocks of products and wood cultures, Kiev, 1953.

S. A. Shilova; V. A. Vilkovich (deratization of vessels), V. D. Kucherenko (soldier.).