Types of bacteria: harmful and beneficial. Beneficial bacteria for the intestines Human harmful and beneficial bacteria model

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The totality of bacteria that inhabit the human body has a common name - the microbiota. In a normal, healthy human microflora, there are several million bacteria. Each of them plays an important role for the normal functioning of the human body.

In the absence of any type of beneficial bacteria, a person begins to get sick, the work of the gastrointestinal tract and respiratory tract is disrupted. Beneficial bacteria for humans are concentrated on the skin, in the intestines, on the mucous membranes of the body. The number of microorganisms is regulated by the immune system.

Normally, the human body contains both beneficial and pathogenic microflora. Bacteria can be beneficial or pathogenic.

There are many more beneficial bacteria. They make up 99% of the total number of microorganisms.

In this position, the necessary balance is maintained.

Among the different types of bacteria that live on the human body, we can distinguish:

• bifidobacteria;
• lactobacilli;
• enterococci;
• coli.

bifidobacteria

This type of microorganisms is the most common, involved in the production of lactic acid and acetate. It creates an acidic environment, thereby neutralizing most pathogenic microbes. Pathogenic flora ceases to develop and cause the processes of decay and fermentation.

Bifidobacteria play an important role in the life of a child, as they are responsible for the presence of an allergic reaction to any food. In addition, they have an antioxidant effect, prevent the development of tumors.

The synthesis of vitamin C is not complete without the participation of bifidobacteria. In addition, there is information that bifidobacteria help to absorb vitamins D and B, which are necessary for a person for normal life. In the presence of a deficiency of bifidobacteria, even taking synthetic vitamins of this group will not bring any result.

lactobacilli

This group of microorganisms is also important for human health. Due to their interaction with other inhabitants of the intestine, the growth and development of pathogenic microorganisms is blocked, pathogens of intestinal infections are suppressed.

Lactobacilli are involved in the formation of lactic acid, lysocin, bacteriocins. This is a great help to the immune system. If there is a deficiency of these bacteria in the intestine, then dysbacteriosis develops very quickly.

Lactobacilli colonize not only the intestines, but also the mucous membranes. So these microorganisms are important for women's health. They maintain the acidity of the vaginal environment, do not allow the development of bacterial vaginosis.

coli

Not all types of E. coli are pathogenic. Most of them, on the contrary, perform a protective function. The usefulness of the genus Escherichia coli lies in the synthesis of cocilin, which actively resists the bulk of pathogenic microflora.

These bacteria are useful for the synthesis of various groups of vitamins, folic and nicotinic acid. Their role in health should not be underestimated. For example, folic acid is essential for the production of red blood cells and the maintenance of normal hemoglobin levels.

Enterococci

This type of microorganism colonizes the human intestine immediately after birth.

They help digest sucrose. Living mainly in the small intestine, they, like other beneficial non-pathogenic bacteria, provide protection against excessive reproduction of harmful elements. At the same time, enterococci are conditionally safe bacteria.

If they begin to exceed the permissible norms, various bacterial diseases develop. The list of diseases is very large. Ranging from intestinal infections, ending with meningococcal.

The positive effect of bacteria on the body

The beneficial properties of non-pathogenic bacteria are very diverse. As long as there is a balance between the inhabitants of the intestines and mucous membranes, the human body functions normally.

Most bacteria are involved in the synthesis and breakdown of vitamins. Without their presence, B vitamins are not absorbed by the intestines, which leads to disorders of the nervous system, skin diseases, and a decrease in hemoglobin.

The bulk of undigested food components that have reached the large intestine are broken down precisely due to bacteria. In addition, microorganisms ensure the constancy of water-salt metabolism. More than half of the entire microflora is involved in the regulation of the absorption of fatty acids and hormones.

The intestinal microflora forms local immunity. It is here that the destruction of the bulk of pathogenic organisms takes place, the harmful microbe is blocked.

Accordingly, people do not feel bloating and flatulence. An increase in lymphocytes provokes active phagocytes to fight the enemy, stimulate the production of immunoglobulin A.

Useful non-pathogenic microorganisms have a positive effect on the walls of the small and large intestines. They maintain a constant level of acidity there, stimulate the lymphoid apparatus, the epithelium becomes resistant to various carcinogens.

Intestinal peristalsis also largely depends on what microorganisms are in it. Suppression of the processes of decay and fermentation is one of the main tasks of bifidobacteria. Many microorganisms for many years develop in symbiosis with pathogenic bacteria, thereby controlling them.

Biochemical reactions that constantly occur with bacteria release a lot of heat energy, maintaining the overall heat balance of the body. Microorganisms feed on undigested residues.

Dysbacteriosis

Dysbacteriosis is a change in the quantitative and qualitative composition of bacteria in the human body . In this case, beneficial organisms die, and harmful organisms actively multiply.

Dysbacteriosis affects not only the intestines, but also mucous membranes (there may be dysbacteriosis of the oral cavity, vagina). In the analyzes, the names will prevail: streptococcus, staphylococcus, micrococcus.

In the normal state, beneficial bacteria regulate the development of pathogenic microflora. Skin, respiratory organs are usually under reliable protection. When the balance is disturbed, a person feels the following symptoms: intestinal flatulence, bloating, abdominal pain, upset.

Later, weight loss, anemia, vitamin deficiency may begin. From the reproductive system, abundant discharge is observed, often accompanied by an unpleasant odor. Irritations, roughness, cracks appear on the skin. Dysbacteriosis is a side effect after taking antibiotics.

If you find such symptoms, you should definitely consult a doctor who will prescribe a set of measures to restore normal microflora. This often requires taking probiotics.

Microorganisms live in the human intestine, which make up a total mass of up to two kilograms. They form the local flora. The ratio is strictly maintained according to the principle of expediency.

The bacterial content is heterogeneous in function and significance for the host organism: some bacteria in all conditions provide support through the proper functioning of the intestines, therefore they are called beneficial. Others are just waiting for the slightest breakdown in control and weakening of the body in order to turn into a source of infection. They are called opportunistic pathogens.

The introduction of foreign bacteria into the intestines that can cause disease is accompanied by a violation of the optimal balance, even if a person is not sick, but is a carrier of the infection.

Treatment of the disease with medicines, especially antibacterial action, has a detrimental effect not only on the causative agents of the disease, but also on beneficial bacteria. The problem is how to eliminate the consequences of therapy. Therefore, scientists have created a large group of new drugs that supply live bacteria for the intestines.

What bacteria form the intestinal flora?

About half a thousand species of microorganisms live in the human digestive tract. They perform the following functions:

• help with their enzymes to break down the substances that have got with the products to normal absorption, absorption through the intestinal wall into the bloodstream;
• produce the destruction of unnecessary residues of the digestion of food, toxins, toxic substances, gases, in order to prevent the processes of decay;
• produce for the body special enzymes, biologically active substances (biotin), vitamin K and folic acid, which are necessary for life;
• participate in the synthesis of immune components.

Studies have shown that some bacteria (bifidobacteria) protect the body from cancer.

Probiotics gradually crowd out pathogenic microbes, depriving them of nutrition and directing immune cells to them.

The main beneficial microorganisms include: bifidobacteria (make up 95% of the entire flora), lactobacilli (almost 5% by weight), Escherichia. Conditionally pathogenic are:

• staphylococci and enterococci;
• mushrooms of the genus Candida;
• clostridia.

They become dangerous when a person's immunity falls, a change in the acid-base balance in the body. An example of harmful or pathogenic microorganisms are shigella, salmonella - the causative agents of typhoid fever, dysentery.

Beneficial live bacteria for the gut are also called probiotics. So, they began to call specially created substitutes for normal intestinal flora. Another name is eubiotics.
Now they are effectively used to treat digestive pathologies and the consequences of the negative effects of drugs.

Types of Probiotics

Preparations with live bacteria were gradually improved and updated in terms of properties and composition. In pharmacology, they are usually divided into generations. The first generation includes drugs containing only one strain of microorganisms: Lactobacterin, Bifidumbacterin, Colibacterin.

The second generation is formed by antagonist preparations containing an unusual flora that can resist pathogenic bacteria and support digestion: Bactistatin, Sporobacterin, Biosporin.

The third generation includes multicomponent drugs. They contain several strains of bacteria with bioadditives. The group includes: Lineks, Atsilakt, Acipol, Bifiliz, Bifiform. The fourth generation consists only of preparations from bifidobacteria: Florin Forte, Bifidumbacterin Forte, Probifor.

According to the bacterial composition, probiotics can be divided into those containing as the main component:

• bifidobacteria - Bifidumbacterin (forte or powder), Bifiliz, Bifikol, Bifiform, Probifor, Biovestin, Lifepack Probiotics;
• lactobacilli - Linex, Lactobacterin, Atsilact, Acipol, Biobacton, Lebenin, Gastrofarm;
• colibacteria - Colibacterin, Bioflor, Bifikol;
• enterococci - Linex, Bifiform, dietary supplements of domestic production;
• yeast-like fungi - Biosporin, Baktisporin, Enterol, Baktisubtil, Sporobacterin.

What should be considered when buying probiotics?

Under different names, pharmacological firms in Russia and abroad can produce the same drugs-analogues. Imported, of course, much more expensive. Studies have shown that people living in Russia are more adapted to local strains of bacteria.

Still better to buy your own drugs

Another negative - as it turned out, imported probiotics contain only a fifth of the declared volume of living microorganisms and do not settle in the intestines of patients for a long time. Before purchasing, you need to consult a specialist. This is caused by serious complications from the misuse of drugs. Patients reported:

• exacerbation of cholelithiasis and urolithiasis;
• obesity;
• allergic reactions.

Live bacteria should not be confused with prebiotics. These are also medicines, but do not contain microorganisms. Prebiotics contain enzymes, vitamins to improve digestion, stimulate the growth of beneficial microflora. They are often prescribed for constipation in children and adults.

The group includes known to practitioners: Lactulose, pantothenic acid, Hilak forte, Lysozyme, preparations from inulin. Experts believe that it is necessary to combine prebiotics with probiotic preparations for maximum results. For this, combined preparations (synbiotics) have been created.

Characterization of first generation probiotics

Preparations from the group of probiotics of the first generation are prescribed to young children when first-degree dysbacteriosis is detected, and also if prophylaxis is necessary, if the patient is prescribed a course of antibiotics.

Primadophilus is an analogue of drugs with two types of lactobacilli, much more expensive than the others, since it is produced in the USA

The pediatrician chooses Bifidumbacterin, Lactobacterin for babies (include bifido- and lactobacilli). They are diluted in warm boiled water and given 30 minutes before breastfeeding. Older children and adults are suitable drugs in capsules, tablets.

Colibacterin - contains dried bacteria of Escherichia coli, is used for prolonged colitis in adults. A more modern monopreparation Biobacton contains an acidophilus bacillus, indicated from the neonatal period.

Narine, Narine Forte, Narine in milk concentrate - contains an acidophilic form of lactobacilli. Comes from Armenia.

Purpose and Description of Second Generation Probiotics

Unlike the first group, second-generation probiotics do not contain beneficial living bacteria, but include other microorganisms that can suppress and destroy pathogenic microflora - yeast-like fungi and spores of bacilli.

Used mainly for the treatment of children with mild dysbacteriosis and intestinal infections. The duration of the course should be observed for no more than seven days, then switch to live bacteria of the first group. Baktisubtil (a French drug) and Flonivin BS contain bacillus spores with a wide spectrum of antibacterial action.

Inside the stomach, spores are not destroyed by hydrochloric acid and enzymes, they reach the small intestine intact

Bactisporin and Sporobacterin are made from hay bacillus, antagonistic properties to pathogenic pathogens, resistance to the action of the antibiotic Rifampicin are preserved.

Enterol contains yeast-like fungi (saccharomycetes). Comes from France. Used in the treatment of diarrhea associated with antibiotics. Active against clostridia. Biosporin includes two types of saprophyte bacteria.

Features of third generation probiotics

Live bacteria collected in combination or several of their strains act more actively. They are used to treat acute intestinal disorders of moderate severity.

Linex - contains bifidobacteria, lactobacilli and enterococci, is produced in Slovakia in a special powder for children (Linex Baby), capsules, sachets. Bifiform is a Danish drug, several varieties are known (Baby drops, chewable tablets, complex). Bifiliz - contains bifidobacteria and lysozyme. Available in suspension (lyophilizate), rectal suppositories.

As part of the drug bifidobacteria, enterococci, lactulose, vitamins B 1, B 6

How are 4th generation probiotics different?

In the production of preparations with bifidobacteria of this group, the need for additional protection of the digestive tract and the removal of intoxication was taken into account. Means are called "sorbed" because the active bacteria are located on activated carbon particles.

Indicated for respiratory infections, diseases of the stomach and intestines, dysbacteriosis. The most popular drugs in this group. Bifidumbacterin Forte - contains live bifidobacteria sorbed on activated carbon, is available in capsules and powders.

Effectively protects and restores the intestinal flora after respiratory infections, with acute gastroenterological pathology, dysbacteriosis. The drug is contraindicated in people with congenital deficiency of the lactase enzyme, with rotavirus infection.

Probifor - differs from Bifidumbacterin Forte in the number of bifidobacteria, it is 10 times higher than the previous drug. Therefore, the treatment is much more effective. It is prescribed in severe forms of intestinal infection, with diseases of the large intestine, dysbacteriosis.

It has been proven that the effectiveness is equated in diseases caused by shigella to antibiotics of the fluoroquinolone series. Able to replace the combination of Enterol and Bifiliz. Florin Forte - includes a lacto- and bifidobacterium composition sorbed on coal. Available in capsule and powder form.

The use of synbiotics

Synbiotics are a completely new proposal in the treatment of intestinal flora disorders. They provide a double action: on the one hand, they necessarily contain a probiotic, on the other hand, they include a prebiotic that creates favorable conditions for the growth of beneficial bacteria.

The fact is that the action of probiotics is not long-lasting. After the restoration of the intestinal microflora, they can die, which again causes a worsening of the situation. Accompanying prebiotics nourish beneficial bacteria, provide active growth and protection.

Many synbiotics are dietary supplements, not medicinal substances. Only a specialist can make the right choice. It is not recommended to make a decision about treatment on your own. The drugs in this series include the following.

Lb17

Many authors refer to the best drugs to date. It combines the beneficial effect of 17 types of live bacteria with extracts of algae, mushrooms, vegetables, herbs, fruits, cereals (more than 70 components). Recommended for course use, you need to take from 6 to 10 capsules per day.

The production does not involve sublimation and drying, therefore the viability of all bacteria is preserved. The drug is obtained by natural fermentation for three years. Strains of bacteria work in different parts of digestion. Suitable for people with lactose intolerance, does not contain gluten and gelatin. Comes to the pharmacy chain from Canada.

Multidophilus plus

Includes three strains of lactobacilli, one - bifidobacteria, maltodextrin. Produced in the USA. Available in capsules for adults. The Polish remedy Maxilak in its composition contains: as a prebiotic oligofructose, as a probiotic - live cultures of beneficial bacteria (three strains from bifidobacteria, five from lactobacilli, streptococcus). Indicated for diseases of the gastrointestinal tract, respiratory system, impaired immunity.

Assigned to children from the age of three and adults 1 capsule in the evening with meals

Which probiotics have targeted indications?

With an abundance of information about bacterial preparations with live microorganisms, some people rush to extremes: they either do not believe in the expediency of using them, or, conversely, spend money on ineffective products. It is necessary to consult a specialist about the use of probiotics in a particular situation.

Infants with diarrhea during breastfeeding (especially those born prematurely) are given liquid probiotics. They also help with irregular stools, constipation, lagging behind in physical development.

Babies in such situations are shown:

• Bifidumbacterin Forte;
• Linex;
• Acipol;
• Lactobacterin;
• Bifiliz;
• Probifor.

If diarrhea in a child is associated with a past respiratory disease, pneumonia, infectious mononucleosis, false croup, then these drugs are prescribed in a short course for 5 days. With viral hepatitis, treatment lasts from a week to a month. Allergic dermatitis is treated with courses from 7 days (Probifor) to three weeks. A patient with diabetes is recommended to take courses of probiotics of different groups for 6 weeks.

For prophylactic administration, Bifidumbacterin Forte, Bifiliz are most suitable during the season of increased incidence.

What is better to take with dysbacteriosis?

It is necessary to be sure of the violation of the intestinal flora to pass a stool test for dysbacteriosis. The doctor must determine which specific bacteria the body lacks, how severe the violations are.

With an established deficiency of lactobacilli, it is not necessary to use drugs only. containing them. Because it is bifidobacteria that are decisive in the imbalance and form the rest of the microflora.

Monopreparations, in which there are only the same type of bacteria, are recommended by the doctor only with a mild degree of violations.

In severe cases, combined means of the third and fourth generations are needed. The most indicated Probifor (infectious enterocolitis, colitis). For children, it is always necessary to select combinations of drugs with lacto- and bifidobacteria.

Means with colibacilli are prescribed very carefully. When identifying ulcers in the intestines and stomach, acute gastroenteritis, probiotics with lactobacilli are more indicated.

Usually, the doctor determines the duration of treatment by the generation of the probiotic:

• I - a monthly course is required.
• II - from 5 to 10 days.
• III - IV - up to seven days.

In the absence of effectiveness, the specialist changes the treatment regimen, adds antifungal agents, antiseptics. The use of probiotics is a modern approach to the treatment of many diseases. This is especially important for parents of young children. It is necessary to distinguish medicines from biological food supplements. Existing dietary supplements with intestinal bacteria can only be used by a healthy person for the purpose of prevention.

There are approximately one hundred trillion cells in the human body, but only a tenth of them are human cells. The rest are microbes. They inhabit our skin, live in the nasopharynx, throughout the intestines. Of course, they are 10-100 times smaller than human cells, but they greatly affect our lives.

This is what a bacterium that causes stomach ulcers looks like under a microscope. Long flagella at the posterior end allow it not only to swim in the contents of the stomach, but also to "anchor" in its mucous membrane. The bacterium stimulates the secretion of hydrochloric acid, the stomach begins to digest itself, and the bacterium feeds on the products of this self-digestion. Nevertheless, sometimes it lives in the stomach of healthy people as a harmless symbiont and, according to some scientists, even brings some benefits, protecting a person from food poisoning.

Symbiosis with humans is clearly beneficial to bacteria: we give them a shelter with constant favorable conditions and abundant food. But they also give us something.

The contribution of microorganisms is most clearly revealed in experiments in which experimental animals are freed from symbiotic microflora. In mice removed from the womb by caesarean section and brought up in sterile conditions, the intestines are very swollen. It is assumed that for the assimilation of food without the participation of symbiotic microbes, the intestine must be longer and thicker. Germ-free mice have longer microscopic villi that line the inner wall of the small intestine. Through these villi, digested food is absorbed. There are fewer microscopic depressions in the intestinal wall in which microbes usually settle. There are fewer immune cells in the gut. Reduced even the number of nerves that control the movements of the intestines. It is assumed that microbes to some extent control the development of the intestine, creating the necessary conditions for themselves. An example of such an interaction in development is known in leguminous plants: nitrogen-fixing microorganisms from the soil cause the plant to develop special nodules on the roots, in which they settle. The plant has the corresponding genes for nodulation, but these genes do not appear unless stimulated by bacteria.

Germ-free mice are very susceptible to infection. In order to infect such a mouse, hundreds of pathogenic microbes are enough, and for an ordinary mouse, one hundred million are needed. Bacteria living in the intestines of normal mice physically block out the aliens and even secrete an antibiotic to kill them.

Bacteria living in the human intestine produce vitamin K, which is not synthesized by our body and is necessary for blood clotting. A number of other vitamins are also supplied by intestinal bacteria. In the intestines of ruminants live microbes that can digest plant cellulose and convert it into glucose, the lion's share of which goes to feed the animal itself. In some marine animals, luminous bacteria live in special glands, facilitating the search for prey or a mate with their light signals.

Recently, Swedish microbiologist Staffan Normark discovered that even the bacterium that causes stomach ulcers is somewhat beneficial. Its role in this disease was discovered more than ten years ago, but it is only now becoming clear why this bacterium is found in the stomach and in many healthy people. It produces an antibiotic that protects against salmonella and other dangerous microorganisms. Apparently, in principle, this is a useful symbiont, which sometimes "goes crazy" and causes ulceration of the stomach wall - perhaps in people with reduced immunity.

Bacteria live almost everywhere - in the air, in water, in soil, in living and dead tissues of plants and animals. Some of them are beneficial, others are not. Harmful bacteria, or at least some of them, are known to most. Here are some names that justifiably cause us negative feelings: salmonella, staphylococcus aureus, streptococcus, cholera vibrio, plague bacillus. But few people know useful bacteria for humans or the names of some of them. Listing which microorganisms are beneficial and which bacteria are harmful will take more than one page. Therefore, we consider only some of the names of beneficial bacteria.

Microorganisms with a diameter of 1-2 microns (0.001-0.002 mm) usually have an oval shape, which can be seen in the photo, which can vary from spherical to rod-shaped. Representatives of the genus Azotobacter live in slightly alkaline and neutral soils throughout the planet up to both polar regions. They are also found in fresh water and brackish marshes. Able to survive adverse conditions. For example, in dry soil, these bacteria can survive up to 24 years without losing viability. Nitrogen is one of the essential elements for plant photosynthesis. They are not able to separate it from the air on their own. Bacteria of the genus Azotobacter are useful in that they accumulate nitrogen from the air, converting it into ammonium ions, which are released into the soil and easily absorbed by plants. In addition, these microorganisms enrich the soil with biologically active substances that stimulate plant growth, help to cleanse the soil from heavy metals, in particular, from lead and mercury. These bacteria are useful to humans in areas such as:

1. Agriculture. In addition to the fact that they themselves increase soil fertility, they are used to obtain biological nitrogen fertilizers.
2. The medicine. The ability of representatives of the genus to secrete alginic acid is used to obtain drugs for gastrointestinal diseases that depend on acidity.
3. food industry. The already mentioned acid, called alginic acid, is used in food additives to creams, puddings, ice cream, etc.

bifidobacteria

These microorganisms, 2 to 5 microns long, are rod-shaped, slightly curved, as seen in the photo. Their main habitat is the intestines. Under adverse conditions, bacteria with this name quickly die. They are extremely useful for humans due to the following properties:

• supply the body with vitamin K, thiamine (B1), riboflavin (B2), nicotinic acid (B3), pyridoxine (B6), folic acid (B9), amino acids and proteins;
• prevent the development of pathogenic microbes;
• protect the body from the ingress of toxins from the intestines;
• accelerate the digestion of carbohydrates;
• activate parietal digestion;
• help absorption through the intestinal wall of calcium, iron, vitamin D ions.

If dairy products have a prefix to the name "bio" (for example, biokefir), this means that it contains live bifidobacteria. These products are very useful, but short-lived.

Recently, drugs containing bifidobacteria have begun to appear. Be careful when taking them, because, despite the undoubted benefits of these microorganisms, the usefulness of the drugs themselves has not been proven. The research results are rather contradictory.

lactic acid bacteria

More than 25 species of bacteria belong to the group with this name. They are predominantly rod-shaped, less often - spherical, as shown in the photo. Their size varies greatly (from 0.7 to 8.0 microns) depending on the habitat. They live on the leaves and fruits of plants, in dairy products. In the human body, they are present throughout the gastrointestinal tract - from the mouth to the rectum. Most of them are not harmful to humans at all. These microorganisms protect our intestines from putrefactive and pathogenic microbes.
They get their energy from the process of lactic acid fermentation. The beneficial properties of these bacteria have been known to man for a long time. Here are just a few of their applications:

1. Food industry - production of kefir, sour cream, fermented baked milk, cheese; fermentation of vegetables and fruits; preparation of kvass, dough, etc.
2. Agriculture - Fermentation of silage (ensiling) slows down the development of mold and contributes to a better preservation of animal feed.
3. Traditional medicine - treatment of wounds and burns. That is why it is recommended to lubricate sunburn with sour cream.
4. Medicine - the production of drugs to restore the intestinal microflora, the female reproductive system after infection; getting antibiotics and a partial blood substitute called dextran; production of drugs for the treatment of beriberi, gastrointestinal diseases, to improve metabolic processes.

Streptomycetes

This genus of bacteria consists of almost 550 species. Under favorable conditions, they form threads with a diameter of 0.4-1.5 microns, resembling mushroom mycelium, as seen in the photo. They live mainly in the soil. If you have ever taken drugs such as erythromycin, tetracycline, streptomycin or levomycetin, then you already know how useful these bacteria are. They are manufacturers (producers) of a wide variety of drugs, including:

• antifungal;
• antibacterial;
• antitumor.

In the industrial production of drugs, streptomycetes have been used since the forties of the last century. In addition to antibiotics, these beneficial bacteria produce the following substances:

In fairness, it should be noted that not all streptomycetes are equally useful. Some of them cause potato disease (scab), others are the cause of various human ailments, including blood diseases.

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The word "bacteria" in most people is associated with something unpleasant and a threat to health. At best, sour-milk products are remembered. At worst - dysbacteriosis, plague, dysentery and other troubles. Bacteria are everywhere, good and bad. What can microorganisms hide?

What is bacteria

Bacteria in Greek means "stick". This name does not mean that harmful bacteria are meant.

This name was given to them because of the shape. Most of these single cells look like rods. They also come in squares, stellate cells. For a billion years, bacteria do not change their external appearance, they can only change internally. They can be mobile and immobile. Bacteria Outside, it is covered with a thin shell. This allows her to keep her shape. Inside the cell there is no nucleus, chlorophyll. There are ribosomes, vacuoles, outgrowths of the cytoplasm, protoplasm. The largest bacterium was found in 1999. It was called the "Gray Pearl of Namibia". Bacteria and bacillus mean the same thing, only they have a different origin.

Man and bacteria

In our body, there is a constant struggle between harmful and beneficial bacteria. Through this process, a person receives protection from various infections. Various microorganisms surround us at every step. They live on clothes, they fly in the air, they are omnipresent.

The presence of bacteria in the mouth, and this is about forty thousand microorganisms, protects the gums from bleeding, from periodontal disease and even from tonsillitis. If a woman's microflora is disturbed, she may develop gynecological diseases. Compliance with the basic rules of personal hygiene will help to avoid such failures.

Human immunity depends entirely on the state of the microflora. Almost 60% of all bacteria are found in the gastrointestinal tract alone. The rest are located in the respiratory system and in the genital. About two kilograms of bacteria live in a person.

The appearance of bacteria in the body

A newly born baby has a sterile intestine.

After his first breath, many microorganisms enter the body, with which he was not previously familiar. When the baby is first attached to the breast, the mother transfers beneficial bacteria with milk that will help normalize the intestinal microflora. No wonder doctors insist that the mother immediately after the birth of her child breastfeed him. They also recommend extending such feeding as long as possible.

Beneficial bacteria

Useful bacteria are: lactic acid, bifidobacteria, E. coli, streptomycents, mycorrhiza, cyanobacteria.

All of them play an important role in human life. Some of them prevent the occurrence of infections, others are used in the production of medicines, and others maintain a balance in the ecosystem of our planet.

Types of harmful bacteria

Harmful bacteria can cause a number of serious diseases in humans. For example, diphtheria, tonsillitis, plague and many others. They are easily transmitted from an infected person through air, food, touch. It is the harmful bacteria, whose names will be given below, that spoil food. They give off an unpleasant odor, rot and decompose, and cause disease.

Bacteria can be gram-positive, gram-negative, rod-shaped.

Names of harmful bacteria

Table. Harmful bacteria for humans. Titles

Titles	Habitat	Harm
Mycobacteria	food, water	tuberculosis, leprosy, ulcer
tetanus bacillus	soil, skin, digestive tract	tetanus, muscle spasms, respiratory failure
Plague wand (considered by experts as a biological weapon)	only in humans, rodents and mammals	bubonic plague, pneumonia, skin infections
Helicobacter pylori	human stomach lining	gastritis, peptic ulcer, produces cytotoxins, ammonia
anthrax bacillus	the soil	anthrax
botulism stick	food, contaminated dishes	poisoning

Harmful bacteria are able to stay in the body for a long time and absorb useful substances from it. However, they can cause an infectious disease.

The most dangerous bacteria

One of the most resistant bacteria is methicillin. It is better known under the name "Staphylococcus aureus" (Staphylococcus aureus). can cause not one, but several infectious diseases. Some types of these bacteria are resistant to powerful antibiotics and antiseptics. Strains of this bacterium can live in the upper respiratory tract, open wounds and urinary tracts of every third inhabitant of the Earth. For a person with a strong immune system, this is not dangerous.

Harmful bacteria to humans are also pathogens called Salmonella typhi. They are the causative agents of acute intestinal infections and typhoid fever. These types of bacteria that are harmful to humans are dangerous because they produce toxic substances that are extremely life-threatening. During the course of the disease, intoxication of the body occurs, a very strong fever, rashes on the body, the liver and spleen increase. The bacterium is very resistant to various external influences. It lives well in water, on vegetables, fruits and reproduces well in milk products.

Clostridium tetan is also one of the most dangerous bacteria. It produces a poison called tetanus exotoxin. People who become infected with this pathogen experience terrible pain, convulsions and die very hard. The disease is called tetanus. Despite the fact that the vaccine was created back in 1890, every year on Earth 60 thousand people die from it.

And another bacterium that can lead to the death of a person is It causes tuberculosis, which is resistant to drugs. If you do not seek help in a timely manner, a person may die.

Measures to prevent the spread of infections

Harmful bacteria, the names of microorganisms are studied from the student bench by physicians of all directions. Every year, healthcare is looking for new methods to prevent the spread of infections that are dangerous to human life. With the observance of preventive measures, you will not have to waste your energy on finding new ways to deal with such diseases.

To do this, it is necessary to identify the source of the infection in time, determine the circle of the sick and possible victims. It is imperative to isolate those who are infected and disinfect the source of infection.

The second stage is the destruction of the ways through which harmful bacteria can be transmitted. To do this, carry out appropriate propaganda among the population.

Food facilities, reservoirs, warehouses with food storage are taken under control.

Each person can resist harmful bacteria in every possible way strengthening their immunity. Healthy lifestyle, observance of elementary hygiene rules, self-protection during sexual contact, use of sterile disposable medical instruments and equipment, complete restriction from communication with quarantined people. When entering the epidemiological region or the focus of infection, it is necessary to strictly comply with all the requirements of the sanitary and epidemiological services. A number of infections are equated in their impact to bacteriological weapons.