Objects of sanitary microbiology - the microscopic flora of this world and its ability to influence human he alth and population. Research in this area gives scientists an idea of the factors that correct the incidence and epidemiological situation. However, not only for epidemiologists, this science reveals a lot of new and useful information: microbiology is also relevant for hygienists.
Importance of the topic
Medical and sanitary microbiology is a science through which it is possible to assess the danger of various environments surrounding a person. Soil, air and water masses, everyday household items used by people are studied. Within the framework of microbiology, objects detected on medical equipment are examined. The task of scientists is to determine and clarify all possible mechanisms and factors for the transmission of pathogens of various infectious diseases. Particular attention is paid to intestinal, wound and airborne transmission.
As part of teaching the basics of sanitary microbiology in educational institutions, students are told how toreceive samples so that their studies show the correct results, by what methods the analyzes are carried out. Already at the stage of primary education, students should be aware of the permissible levels of pollution, as well as have an idea of the documentation that sets these levels. In our country, there are special norms, rules adopted by legislative structures. Accounting for this documentation is mandatory for all those working in this area. Guidelines and other documents regulating the work of specialists in the field of microbiology have been developed.
Nuances of the process
The tasks and methods of sanitary microbiology rarely include the determination of species in specific samples, their exact identification. As a rule, scientists work with some conditional microbial groups. To determine belonging to one, it is necessary to identify a certain minimum set of features. Morphology, cultivation, enzymatic features are evaluated.
About environments: soil
Sanitary soil microbiology is one of the main subsections of science. Its importance cannot be underestimated, because it is the soil that is the reservoir of many microscopic life forms. In combination with flora and fauna, such creatures form complex biogeocenoses. The structure and typical affiliation of a particular soil determine which microorganisms will live here, what is their density, activity, and how diverse the composition of the colonies is. The role is played by the organic, mineral composition of a particular site, physical condition, chemicalfeatures, heating, acidity and humidity levels - in a word, all the nuances that determine the state of the soil.
Scientists involved in soil sanitary microbiology have found that up to 6 tons of microbes can be contained in a 15-cm layer within one hectare. The highest density of such life forms is at a depth of 10-20 cm, but the layers lying over a meter from the surface are poor in microorganisms. From five meters and deeper, the soil is highly likely to be sterile.
Processes and their causes
One of the main tasks of sanitary microbiology is to determine the causes of pathogenic life forms entering the environment, finding out how they multiply and develop. Regarding soils, in particular, it has been established that the main percentage of dangerous microorganisms enters the soil with pus, saliva, feces, urine and other organic excretions of animals, humans, birds. The bodies of dead creatures are the source of dangerous microbes, especially if infectious pathologies became the cause of death. Soil contamination with pathogenic and conventionally considered such forms of life is observed during the discharge of wastewater from industrial facilities, as well as domestic and sewer.
One of the goals of sanitary microbiology is to determine the characteristics of pathogenic microbes, including the timing of their survival in some environment. It has been established that they vary significantly in the soil. Some life forms that do not generate spores can exist for days and months, others for years and decades.
For spore-producing pathological bacteria, the soil may be a natural placeexistence. This explains, for example, gangrene, tetanus against the background of contamination of the wound with earth. Some organisms live in the soil, die off, which leads to the formation of substances that are toxic to humans. Usually death occurs due to lack of water, heat, nutrients, due to the influence of direct sunlight or the appearance of antagonistic microbes.
We'll check everything
Soil is such an environment for sanitary microbiology, the research of which is extremely important, since their conclusions are relevant for many sciences, including practical medicine. The main task of studying the soil is to prevent infection of people, sanitary control and supervision, and taking into account the compliance of the situation with the standards. Specialists in the science in question are involved in the investigation of catastrophes and epidemics, environmental accidents. Soil analysis is made brief or extended - it depends on the requirements of the case. For example, routine monitoring of the situation requires an assessment of faecal contamination, if any. If a high concentration of bacteria is detected, which makes it possible to talk about such pollution, the region is considered unfavorable in terms of sanitary indicators. To assess the condition of the soil, samples are taken for laboratory testing and the content of Escherichia coli, streptococcus is detected. If present, contamination is fresh. Cyto-, enterobacteria indicate stale, some forms of clostridia point to old.
The methods of sanitary microbiology used in the study of soils are sometimes used as part of a preventivestudies to identify indicators, the analysis of which allows us to assess the likelihood of an epidemic. After receiving the results of laboratory tests, the data is compared with the standards adopted in the country. It is important not only to assess the content of life forms and their types, but also the composition of the soil, the influence of climate. At the moment, there is no single standard for assessing soil within the framework of the science described.
Water is the basis of life
Sanitary microbiology of water is no less important branch of science than the one discussed above. Like the earth, the liquid of open reservoirs is the environment for the existence of microscopic organisms, algae, and protozoa. It is customary to talk about autochthonous and allochthonous microflora. The second type is micro-organisms coming from the earth, air and from various creatures. Water is the area of localization of purifying biological processes, the task of which is to get rid of allochthonous microflora.
Sanitary microbiology of water is a science that studies the concentration and composition of microorganisms in water bodies and the dependence of these indicators on various factors. Thus, it has been established that the presence of organic substances strongly affects the concentration of microbes. Groundwater is considered the cleanest, since microflora lingers in the soil when liquid passes through it. But open water bodies are rich in microbes, since a large amount of a substrate useful for microflora is dissolved in the water. This comes from sewers and sewage, industrial waste.
Relevance of the problem
One of the goals of the sanitarymicrobiology - to assess the impact on the environment of a person and the products of his activity. Particular attention is paid to wastewater. Their volumes are growing every year, and a huge amount of microflora enters the reservoirs. With such volumes, the liquid does not have time to purify itself, and for every milliliter there are several million microbes.
Sanitary microbiology establishes how powerful the impact of contaminated water on the spread of disease. It has long been proven that this is an important epidemiological factor for intestinal diseases. Discharges of sick individuals, carriers of pathogens, end up in open water bodies, from where they gradually penetrate into drinking water. All this threatens the spread of polio, dysentery, hepatitis, typhoid and other dangerous diseases.
About terms and phenomena
As can be concluded from all of the above, sanitary microbiology is a science whose task is to protect the environment from pathogenic life forms. The specialists who have chosen it as their field of activity are investigating the influence of microscopic external flora on human he alth. The discipline is independent, dedicated to the microbiota and its features to harm the human population.
The main task of sanitary microbiology is the assessment of external objects according to the main indicators considered in this science. Norms are also being developed that reflect in which case objects are safe. Microbiologists must generate new research methods, expertly evaluate their accuracy and effectiveness, and apply such methods tostudying the external environment. The tasks of science include the formation of recommendations regarding the methods and ways of improving the external environment through the impact on the microflora. Professionals in microbiology should evaluate the effectiveness of such activities.
An equally important task of sanitary microbiology is the study of the patterns of the life cycle of microscopic life forms that inhabit the human environment. At the same time, attention is paid not only to the relationship with the human population, but also to the existence of microbes and bacteria in the ecological system.
Techniques of science
Modern sanitary microbiology uses two main methods of work - this is the direct detection of microscopic forms and indirect indication, which allows to assess the likelihood of the presence of microflora. The first option is considered to be much more reliable, but the level of sensitivity is still low, and the work itself is laborious. The complexity of the definition is associated both with a low concentration and with the uneven colonization of microbes in the environment, with competition between different species, and the presence of saprophytes. The causative agents are constantly changing, which further complicates the task. As a rule, a direct determination is made when there are epidemiological indications for this.
Food microbiology has an alternative method for identifying life forms - indirect. It is easier to implement, this approach is more accessible. There are two criteria on the basis of which the studied medium is evaluated: microbial count, concentration of representative microscopic formslife. The microbial count is the number of organisms per gram or cubic centimeter. It is believed that the higher the value, the higher the probability of the presence of pathogenic organisms, which means that it is possible to assess the epidemic situation.
Nuances of the question
The main task of sanitary microbiology of air, soil, food, medical equipment and other objects is to assess whether there is a pathological microflora in a particular area and how numerous it is. At present, it is quite difficult to cope with this issue - this is due to both the imperfection of technologies and the peculiarities of the objects under study. Currently applicable methods take into account that the main source of infectious pathogens are warm-blooded creatures, including humans. It is these populations that release pathogenic life forms into the environment.
When studying soil and water, air and food products in sanitary microbiology, the peculiarities of the natural environment of existence for pathogenic and conditionally being such life forms are taken into account. For many, this is, for example, the intestinal tract of warm-blooded creatures. The detection of typical intestinal microflora in some sample indicates a high probability of the presence of pathogens of cholera, typhoid. For other life forms, the biotope is the oral cavity. By examining microorganisms, one can assess the unfavorable situation of the region, thanks to which their concentration has become a sanitary indicative factor.
Sanitary demonstration - what are they?
These include only those microscopic life forms that are permanently containedin the secretions of warm-blooded creatures, enter the environment in a sufficiently high concentration, do not have alternative natural reservoirs. Such microflora should retain the ability to survive in the environment after isolation for a certain time period comparable to the survival of pathogenic microflora.
Microorganisms capable of active reproduction outside the body of a warm-blooded creature cannot be taken as sanitary indicators. Correction of biological properties is also not allowed when it enters the space external to the carrier's body. Microbiologists are only interested in typical life forms so that diagnosis is not too much of a problem.
When choosing sanitary-indicative forms of life, only those that can be accurately and easily calculated and evaluated by modern methods and means are taken into account. The growth of such microorganisms in the nutrient substrate should not be controlled and depend on other representatives of microscopic life forms. An important condition is the uniform distribution of microorganisms in the external environment. For example, when examining dense food items, homogenization is necessary to assess microbial content.
The choice of a microorganism as a sanitary indicator is possible only if it occurs both in the host organism and in the external environment in a higher concentration than a pathogenic life form.
All at once: is it possible?
Determining the extent to which a particular microorganism variant is applicable for analysis as a sanitary indicator, it is necessary to checkto meet all of the above conditions. The more matches are observed, the more accurate the result of analyzes using it will be. In practice, it is not always possible to choose a microflora that would fully satisfy all of the above requirements. In this case, it is necessary to stop at the closest to the ideal set of qualities.
About liquid
To determine how safe water used for drinking, food and products, mineral waters, medicinal and table waters, surface sewage, open, as well as therapeutic mud, one should resort to unified methods. They are regulated by the laws of the country, GOSTs have been adopted, guidelines have been developed.
For drinking water, it is established that per milliliter of liquid there should be no more than a hundred microbes in general, while the index per liter should be within three. The presence of Escherichia, coliphages in a liter of water is unacceptable. When they are detected, you can not use water for drinking. When analyzing 25 liters, protozoa, helminth eggs should not be detected.
About Standards: Continuing the Review
When identifying the characteristics of products intended for feeding children, it is necessary to assess the presence of intestinal pathogens. At 10 cubic centimeters there should not be a single sample, at 100 cm 3 - there should be no pathogenic bacteria. There can be up to hundreds of colony-forming units of microorganisms in each cubic centimeter.
For fermented milk products intended for children, 3 cm3 should not berepresentatives that can provoke intestinal diseases. When analyzing 10 cm3, coli and streptococcus should not be detected, and five times more in volume - no pathogenic bacteria. For beverages and cereals, cottage cheese, each gram should be free of representatives of these life forms, including Salmonella.
Food microbiology
To some extent, it is thanks to this science that the food industry in the form in which it is known to modern man can exist. The products contained in the refrigerators of ordinary citizens are the result of the work of scientists specializing in microbiology. With regard to food, they are developing new methods to protect products from dangerous life forms without losing taste and aroma.
In stores you can find a huge variety of products, the production of which is only possible through cultivated microscopic life forms. People rarely think, but it is thanks to such colonies, put at the service of humanity, that the production of kefir, cottage cheese and sour cream, and other similar products has become available on an industrial scale.
Another important industry is egg microbiology. This product inside is exceptionally sterile and rich in lysozyme (protein structure), which is able to destroy pathological microscopic life forms that have leaked through the natural barrier - the shell. In order for the egg to be stored for a long time and not be a source of danger to humans, microbiologists are developing storage methods, norms and rules in which natur althe ability to protect content is maintained for a long time.
