From Big Medical Encyclopedia

INDICATION OF MICROORGANISMS (Latin indicatio, from indicare to specify, define) — a complex of microbiological methods of a research for definition in objects of the environment (air, water, the soil, surfaces of various objects, etc.) pathogenic for people and animal fungi, bacteria, rickettsiae, viruses.

Development And. m as the section of microbiology it is connected with clarification of value of water, air, the soil as factors of transfer of the infectious beginning. Value I. m increased in system of actions for studying of the biosphere in connection with the accelerated growth of the cities, density of the population and connected with this pollution of the soil, water sewage and human excrement. In the second half of 19 century data on presence of pathogenic microbes at objects of the environment begin to appear. R. Koch and JI. Pasteur find in the soil of activators of a mephitic gangrene, A. Nicolaier — tetanus. L. Pasteur, and then and other scientists conduct a research of air on existence of microorganisms in it. In Russia there are works of scientists and doctors in whom questions of influence of a polluted air on incidence in prisons, intrahospital infections are taken up. During this period original methods of catching of bacterial aerosols are offered. K. Flyugge (1898), and then P. N. Lashchenkov (1927) put forward the concept about a role of the airborne mechanism by transfer of the infectious beginning.

Since methods of direct detection of pathogenic microbes in the environment not always yielded reliable results, there was a need of development of indirect indicators of pollution of water, the soil, air.

At And. m use means and methods of researches which are applied to laboratory diagnosis of infectious diseases and a dignity. - mikrobiol, researches.

Pathogenic microflora is concentrated in allocations of the patient (fecal masses, a phlegm etc.). Hit of allocations in water, the soil, air leads to reduction of concentration of pathogenic microorganisms in an object. Saprophytes join microflora of allocations. It complicates And. m in objects of the environment.

Efficiency And. the m substantially depends on the correct sampling from objects of the environment, their preparation to mikrobiol. to a research and methods of a research.

Sampling from objects of the environment is made by means of devices — Dyakonov, Krotov, Rechmensky's bakterioulovitel, etc. (see. Samplers ), impactors (see. Indication of weapons of destruction ), batometr (see), etc. At the same time special attention is paid at choice of the place of possible greatest pollution of objects by pathogenic microflora.

Preparation of tests for a research pursues the aim to increase probability of detection in the studied material of the corresponding microorganisms. Microflora of water is concentrated. Apply physical to this purpose. methods, in particular filtering through Berkefeld's candles, Shamberlan or, most often, via nitrocellulose membrane filters (see. Bacterial filters ); physical. - chemical ways — sedimentation by coagulants, the agglutinating serums, a method of flotation, and also a combination of the listed ways.

Concentration of viruses in the studied water is carried out along with sampling for what on 2 — 4 days immerse gauze tampons — «small pillows» in the studied water. On other way of test of water transfer to flat-bottomed flasks on which bottom lower a magnet. Under a stopper of a flask suspend on a thread a gauze tampon so that it was completely submersed in liquid. Flasks place on electromagnetic mixers or in the shaking machine and their contents mix 30 — 45 min. for adsorption and concentration of viruses on tampons. Further tampons wring out in a sterile vessel, alkalinize the received liquid for the best desorption of viruses sterile solution of soda or disubstituted sodium phosphate with pH 8,0. Then the tampon is repeatedly immersed in this liquid and again wrung out.

Preparation of tests of the soil for a research begins with dilution of microflora, i.e. preparation of suspension in cultivation 1:2, 1:3. For simplification of a desorption of viruses from parts of the soil the last is alkalinized. For the subsequent concentration of microflora in suspensions of the soil use the methods applied at a research of water. From surfaces of various objects microflora is washed away the sterile tampons moistened with isotonic solution of sodium chloride and then desorbed and concentrated in the mentioned ways.

The received concentrate of microflora, except pathogenic microbes, contains a large number of the saprophytes which are actively growing on mediums and exerting antagonistic impact on pathogenic microorganisms. For suppression of saprophytes of suspension are processed by mix of antibiotics. The microbic suspensions intended for a research on existence of imperfect pathogenic fungi mix with equal amount of solution of biomycin, penicillin or streptomycin (on 500 — 1000 PIECES on 1 ml of a suspension) and maintain 30 — 60 min. in the thermostat. A subsample, intended for indication of rickettsiae and viruses (except for a research on ornithoses), process mix of penicillin (1000 PIECES on 1 ml) and streptomycin (1000 PIECES on 1 ml). The material intended for a research on spore-forming microflora is exempted from vegetative microorganisms warming up of microbic suspension at t ° 50 — 60 ° within 30 min.

The microbiological research of the prepared object begins with its crops on inhibitory mediums (see). For suppression of growth of saprophytes by Wednesdays add a methylrosanilinum chloride, antibiotics and other drugs. Purification of suspensions of foreign microflora can be reached by preliminary infection of animals with rubbing in of the studied material in the scarified leather of an animal or immersion of the shaved site of skin in the studied water at several o'clock. Biol, a way of cleaning is applicable only for indication of microbes of zoonotic group. This method is often used at indication of rickettsiae, causative agents of leptospirosis, a tularemia, a malignant anthrax, etc.

The sowed mediums, including cultures of fabrics and chicken embryos, incubate in the thermostat. Release of pure growth and identification of microorganisms are carried out on standard to bacteriological techniques (see).

For timely carrying out protivoepid, actions time spent for carrying out is of great importance And. m. Therefore at And. m, except classical, widely apply the accelerated and express methods of indication.

Classical mikrobiol, methods of a research are counted on obtaining the answer in several days and even weeks. According to these methods crops are within a day grown up on mediums. Then colonies, morphology and tinktorialny properties of microorganisms are studied, pure growth of the activator is emitted, the detailed research cultural, biochemical, serol, and pathogenic properties of the allocated strain is conducted.

The accelerated methods allow to reduce time of a research considerably. It is reached, first, by entering into mediums of growth-promoting factors of microbes (yeastrels, hydrolyzates of casein, a filtrate of culture sartsin, a potato stick, etc.); secondly, a research of cultures after the reduced term of a podrashchivaniye (4 — 6 hours), i.e. before achievement of a stationary growth phase by them; thirdly, due to reduction of number of stages of researches. Such methods are reaction of increase of a caption of a phage, acceleration of obtaining results of fermentation of sugars by introduction on Wednesdays of a large number of microbes at rather trace amount of sugar, etc.

Reaction of increase of a caption of a phage is the original technique allowing to carry out And. m without release of pure growth (see. Reaction of increase of a caption of phages ). The essence of a technique comes down to identification of increase in quantity of phage particles at their meeting with homologous bacteria.

Express methods I. m allow to define infectiousness of an object in more short time in comparison with the accelerated methods. Reduction of time is reached by an exception of the scheme of a research of process of cultivation of cultures and definition their biochemical, activities. Together with concentration of microflora in the studied object express methods I. m take several hours or tens of minutes. Reactions belong to these methods precipitations (see), gaptokholevy flocculation using membrane filters, agglomeration of alizaric suspension agglutinins, coal agglomeration, indirect hemagglutinations (see) and method immunofluorescence (see).

Reaction of gaptokholevy flocculation belongs to number serol, reactions. The principle of specific agglomeration of the cholesterol adsorbing hapten of a required microorganism (a polisakharidno-cholesteric complex) on the surface is its basis. Reaction consists of three stages: preparations of solution of cholesterol, preparation of gaptokholevy antigen and agglomeration of gaptokholevy antigen immune serum.

Reaction of agglomeration of alizaric antibodies is based on adsorption of specific antibodies alizaric suspension with its subsequent crowding which is caused a sensitization of alizaric suspension antibodies the homologous microorganisms which are in the studied material.

See also Indication of weapons of destruction .

Bibliography: Adamov A. K. A method of bystry detection of pathogenic microbes by means of alizaric suspension antibodies, Riga, 1959; Artyomova V. N. Researches of a possibility of indication of bacteria in water by a spektro-ultramicroscopic method, the Gigabyte. and dignity., No. 9, page 75, 1972; Bagdasaryan G. A. and L about in c of e in and the p E. L. Indication and an inactivation of intestinal viruses in objects of external environment, M., 1972, bibliogr.; Grigorieva L. V. Enteroviruses in external environment, M., 1968, bibliogr.; Grinkh. ileynv. Aerosols — dust, smokes and fogs, the lane with English, L., 1972; Zuev V. E. The laser — the meteorologist, L., 1974, bibliogr.; Karalnik B. V. Erythrocyte diagnosticums, M., 1976; Karpuzidi K. S. and Drozhev-k and N and M. S. Use of environments with lysates of microbes-kormilok for the purpose of acceleration of bacteriological diagnosis of a typhoid, Zhurn, mikr., epid, and immun., No. 6, page 92, 1957; Kucherenko V. D. Indication of pathogenic microbes in external environment, M., 1964, bibliogr.; Methodical instructions on allocation of cytopathic enteroviruses from drain waters, sost. V. A. Kazantseva and G. A. Bagdasaryan, M., 1965; V. V., Kiktenko V. S. and Kucherenko V. D Starlings. Survival and indication of pathogenic microbes in external environment, M., 1966, bibliogr.; T and m and to about in V. D. and about l d-farb D. M. Reaction of increase of a caption of a phage (RNF), M., 1962, bibliogr.; F and x - m and B. A N. Microbiological refractometry, M., 1967, bibliogr.

V. D. Kucherenko.