Emergencies of respiratory viral infections - microbiology. Zbudniki GRVI. taxonomy. characteristic. Microbiological diagnostics. specific prevention and treatment. Diagnosis and differential diagnosis of influenza

Golovna / Optimization of work

Microbiology of the influenza virus has been studied to the best of its ability. Its external parameters, future and power are indicated. The removal of data allows the “behavior” of one strain to be transferred.

The science of microbiology relates the influenza virus to the Orthomyxovirus family(Orthomyxoviridae). This virus is the most widespread in nature, and also the most dangerous (according to some scientists). These types of cases have a very high mortality rate. Others are less pathogenic, but through their wide spread they can bring great economic harm. In addition, the mortality rate in cases of illness, expressed in absolute numbers, is still high, unimportant to the not so high indicators.

Microbiology brings influenza to the orthomyxovirus family

Zbudnik influenza has a spherical shape on tissue cultures. In the native form (in preparations taken from people and creatures) it is thick, thread-like, and curved. The size of the virion is 80 to 120 nm. The structure of the viral part consists of the following elements:

External membranes, which are composed of lipids. This shell is removed by the virus, “removing” from the tissue, in the process of synthesis.

There are “spikes” on the surface- protein molecules rooted in the membrane that protrude above the surface. The great end of their meetings. There are two types of stench:

  • hemagglutinin – protein receptor (HA);
  • neuraminidase - enzyme (NA).

Membrane protein(M2). It has fragmented tubules that pass through the membrane. Ions pass through these tubules when the virus “nurses” in the cell cytoplasm. When the membrane breaks down, the genome changes.

Matrix protein(M2). It dissolves the inner capsule, spread under the ice ball, which contains the gene.

Nucleoproteins(NP). The internal part of the virus is nose genetic information. The smell is represented by 8 RNA fragments of varying sizes.

Polymerase proteins. These enzyme proteins serve the process of replication (multiplication) in the host cell. There are currently 3 types of them.

Non-structural proteins. Їх 2 tipis. They play an additional role when the virus multiplies.

Biochemistry, as well as microbiology, has been studied well against the influenza virus. Based on the decoding of its genome, a difference in the nucleotide sequence of various serotypes was revealed, which indicates the significance of their pathogenicity. The sequence of chemical reactions that occur during its reproduction is determined. Good Vivcheni antigenic power, detailed methods of laboratory diagnostics

Antigenic structure and classification

Classification and systematization in microbiology is done by taxonomy, the influenza virus is related to the RNA viruses of the Orthomyxovirus family. This homeland includes 6 canopies, 3 of them are influenza diseases.

In this manner, A, B and C are not just different views flu. The skin virus represents its own genus, which includes one species. Name the genus and species with which they flee. For example, influenza A has a Latin species name InfluenzaAvirus, this type of influenza is the only representative of the same genus InfluenzaAvirus. Influenza B IC has a similar nomenclature.

The Orthomyxovirus family includes 6 species, 3 of which are influenza pathogens.

The presence of viruses in different species is based on their importance for antigenic activity, the peculiarities of interaction with the host’s body, the stage of pathogenicity, as well as other signs. The diversity of antigens between influenza A, B and C is revealed on the level of structural protein (M1) and nucleoproteins (NP), and internal antigens, which may be species specific.

Within species, division into serotypes, strains, variants, and isolates is allowed. Depending on the serotype of the influenza virus, it depends on which type of surface antigen enters the warehouse. Є 18 subtypes of hemagglutinin (mostly mild), 11 subtypes of neuraminidase. Stinks are indicated by an Arabic numeral. For example, the H5N1 flu affects hemagglutinin 5 subtypes and neuraminidase 1 subtypes.

Nomenclature of zbudniks

In order to systematize information about the virus, compare it, report different types of infection, and also for other purposes, adopt standards for assigning specific isolates to the virus. An isolate is a culture that can be seen directly from a sample taken from animals or people. When nomenclature designated isolate, indicate:

  • virus type (A, B and C);
  • the type of creature from which the hymn was seen, as in the visions from samples taken from humans, this point is omitted;
  • the name of the geographic area where the sample was taken;
  • virus number;
  • rik vision of culture;
  • serotypes of antigens, the stench is taken from the arch.

For example, a virus of the genus A, seen in the province of Huan from the body of a pumping organism in 2002, numbered 795, as well as antigens - hemagglutinin type 5 and neuraminidase type 1, with the nomenclature name A/duck/Hunan/795/ 2002(H5N1). And the journal of the genus A, visions in New Caledonia from samples taken from people in 1999, may be number 120, hemagglutinin type 1 and neuraminidase type 1 - A/NewCaledonia/120/99(H1N1).

Influenza virus and visions from the body of a jock

There are few strains of influenza B and C currently circulating, and their nomenclature names vary slightly. It has a daily requirement for the type of surface antigens (H and N), since the genus B virus has little stench, so their distribution is not of epidemic significance. And in influenza C, neuraminidase and hemagglutinin disappeared within a day. In influenza genus C, the surface antigen is represented by a different language. Stock name: B/Beijing/184/93 and S/Taylor/1233/47.

Peculiarities of everyday life

U more middlebrow Viruses are unstable and cannot withstand high temperatures, the infusion of disinfectants, or ultraviolet radiation. Infection occurs when the pollen gets into the mucous membrane.

The degree of stench is up to the epithelium of the mucous membrane of the respiratory tract (and even up to the epithelium of the intestinal tract, as well as other organs). Upon contact with the host cell, the viruses attach themselves to it through additional receptors, and the vicoristic and genetic apparatus of the cell begins to reproduce.

The virus, which is consumed in the blood, causes intoxication

The epithelium at the site of infection is accompanied by pain, an inflammatory reaction is formed, which is manifested by catarrhal syndrome. Once the virus enters the bloodstream, intoxication and dystrophic changes in organs develop. The flu is more severe to an aggressive course with high fever, severe intoxication, and damage to the internal organs.

Nonspecific chemical mechanisms are not enough to allow the body to fight off infection. Dressing comes after a sufficient amount of antibodies have been generated. Immunity after an infection depends on the type of illness. With influenza, the pain is usually not persistent. This is due to the high diversity of the antigenic structure of the virus.

Diagnosis and differential diagnosis of influenza

As a routine analysis, serological methods are used. The essence of them is that the material taken from a person (swipe, smears, serum) is treated with a reagent to deliver antibodies to other antigens to the virus. During the hour of observation, a reaction from the antigen to the antibody is observed. The result of the reaction is visualized in different ways. One way is to allow antibodies to remain in the field of a fluorescent microscope until they are detected. There are also other methods.

Pathogenicity of HRV and influenza viruses

Crazy Influenza viruses and other flu viruses are classified according to the level of pathogenicity therefore, which parts of the respiratory tract are important to be affected, and also which syndromes are important when assessing the picture of the disease. However, due to the similarity of the clinical picture, without virological diagnostics, it is impossible to reliably determine what disease caused the illness. Particularly important is the correct diagnosis of influenza, as it has great epidemiological and also clinical significance.

The gastrointestinal tract is rich in diseases: there are nearly 200 of them. Among them are prokaryotes: bacteria, mycoplasma, chlamydia. Diagnosis of acute respiratory diseases viral infections administer medicine Therapists are already distinguishing between clinical symptoms, such as GRD: viral or bacterial. Wednesdays of the GRVI: influenza virus, parainfluenza, rhinovirus, reovirus etc. We have seen close to 200 GRVI weekdays. Only by laboratory methods can one prove that a person is ill with the influenza virus, etc. During the skin epidemic period, the 10th diagnosis of influenza is mild; during the non-epidemic period, the number of infections decreases to 30-40%.

GRIP (from the French grippe - to spit, established by the doctor Sabazh in the 19th century). Synonymous with Italian influenza.

The viral nature of influenza was discovered in 1933. The English teachings Smith and the authors saw in patients with the GRZ virus. In our country, two prominent scientists, A. A. Smorodintsev and L. A. Zilber, discovered a different influenza virus in 1940, which evolved from the virus seen in 1933. In 1974, another influenza virus was discovered. There are currently 3 known flu viruses, which are designated A, B, C. All those uncured illnesses like the flu are associated with the influenza virus A. The influenza virus also periodically causes illness, but it is not as scary as epidemics and pandemics when the virus arises oh flu A.

Influenza A virus, inoculated to the submolecular level. All influenza viruses contain RNA; in the center of the virus particles there is a ribonucleoprotein, which consists of 8 fragments - 8 genes. 1-6 genes encode the synthesis of one protein, and 7-8 genes encode 2 proteins; The influenza virus genome encodes a total of 10 proteins. The RNP units are coated with a protein coat and are also coated with supercapsids. The supercapsid of the influenza virus is composed of a lipoprotein membrane, these cells in which the virus multiplies (the fragments come out of the cells in the way of bruning). It is important that different influenza A viruses multiply in different cells, their surfaces can become significantly irritated. Supercapsids have 2 proteins - enzymes. The stench is evoked from the appearance of thorns:

Hemagglutinin 500-600 spikes. This enzyme can interact with the mucoprotein receptors of cells, so that the virus reacts with them and the virus is adsorbed on the surface of sensitive cells. Such receptors are on the surface of erythrocytes. After adsorption of the virus on erythrocytes and hemagglutination, take blood and add drops to remove the virus: after 1.5 weeks, aglutination is avoided or neither. titrate and add erythrocytes to the skin dilution, which is significant for the strength of virus A. For the detection of immune serum to known antigens The virus allows antibodies to bind to hemagglutinin and prevents the galvanization reaction of hemagglutination. Until now, it is known that the influenza virus has a number of types of hemagglutinin. People know 4 antigenic types of hemagglutinin (indicated by H). The available antigenic variants are: H1 3) H2 (with antigenic variants 1,2,3) H3 (with antigenic variants 1,2,3).

Neuraminidase between the spines of hemagglutinin. cliniform membranes. The role of neuraminidases is in mature cells, but does not help in penetration and exit from cells. Influenza viruses and humans have 2 antigenic variants of the neuraminidase type N1 N2.

The virus looks like a sea urchin - it is spherical, about 100 nm in diameter, covered with spikes.

Antigenic power to influenza A virus

Influenza viruses have a number of antigens: one antigen - the S-antigen, which is bound to the ribonucleoprotein, which is an internal antigen. After the S-antigen, the influenza virus is easily divided into influenza A, influenza B, and influenza C viruses. It is impossible to overlap the antigens here, since it is antigenic specificity. The assistant said that the influenza virus has a V-antigen, but in reality this is what they mean on the surface. : These include hemagglutinin and neuraminidase. These types of influenza virus include:

1. influenza A virus with H0N1 antigens

2. Influenza A virus with H1 N1 antigens. Appearing in 1947 rocі, having circulated 10 rocks (until 1957 rock), appeared on 20 rocks, again appearing in 1957 rocі and circulating dosi.

3. H2 N2 appeared in 1957 and circulated 10 years ago.

4. H3N2 appeared in 1968 and is circulating.

The H0N1 influenza virus was discovered in 1933, and circulated until 1947, and no one has been seen infected for 50 years.

Thus, influenza A virus, which causes illness at the same time, can be of two types. When this situation was explained, it was clear that the virus was circulating at all times, becoming an epidemic and starting in 1957, since it appeared new virus which is identified by two antigens: hemagglutinin and neuraminidase. It really was a pandemic: 2/3 of the Earth’s population fell ill. This virus was known, but in 1968 there was a new epidemic. There is a new virus that is being detected behind the H antigen. Thus, a pattern emerges: the emergence of a new virus is due to the formation of immunity in people. The more the new virus diversifies from the previous one, the more people get sick. This pattern provides a theoretical basis for action to prevent such illness from occurring.

The prevalence of influenza virus A. The prevalence of influenza virus is caused by two genetic processes:

Genetic shift occurs as a result of a new gene change and the exchange of genes during simultaneous reproduction of two influenza viruses in the community

antigenic drift - change in the antigenic warehouse, without completely replace antigen. In the middle of the antigen, minor changes occur. Antigenic drift is based on point mutations of the gene, as a result of a change in the antigen.

Types of infections. There are three types of infections:

productive infection: the virus is adsorbed, penetrates, reproduces and exits. Klitina collapses at this. If this is present in the body, then serious illness occurs.

Asymptomatic infection: reproduction rate is low. Clients suffer less and, on the whole, the body suffers from illness without symptoms, but when sick, there is an infection

latent infection: this type of infection has so far been studied in cell cultures in vitro. However, this type of infection in the human body is not known.

It appears after penetration of the virus that when RNP is formed, it attaches to the nucleus of the cell and thus resides in the cell. RNP is a foreign structure for the cell, and the compactness of the cell is conservative, so that it does not tolerate outsiders, but, prote, RNP seems to be in the middle of the cell. RNP is passed on to cell offspring. It is important that the 20-year failure of the virus is due to this mechanism itself.

INFLUENZA VIRUS: 2 influenza pandemics have been reported: first flu - Spanish flu at 18-20 r. XX century, pandemic in 1957. By this time, 20 million people had died from the flu. The influenza virus and the outbreak of GRZ will shorten the average troubles of life by about 10 years.

Flu is an anthroponosis. The influenza virus in humans is associated with illness in humans (it is also known that the influenza illness in humans is similar to the influenza illness in animals). The path of infection is wind-speckled. The virus is not stable in the global environment.

The gates of infection are the upper respiratory routes. Influenza viruses can spread to the prismatic epithelium of the upper respiratory tract. During reproduction, cells suffer from minor damage to cell necrosis. The rate of reproduction of the virus is even high and in 2-3 years the population of viruses increases by several orders of magnitude. This is why the incubation period for influenza is short. At the first stages of illness there are degenerative-dystrophic changes. There is no burning. If pneumonia develops in these early stages, it will again pass without a strong ignition reaction. Late bronchitis and pneumonia often develop with associated bacterial infection. As soon as sectional material of people who died from influenza pneumonia is examined, staphylococcus is then detected by microscopy, thus causing mixed infections.

Newsletters of ARVI (acute respiratory infections)

The gastrointestinal tract is rich in diseases: there are nearly 200 of them. Among them are prokaryotes: bacteria, mycoplasma, chlamydia. The diagnosis of acute respiratory viral infections is made by a doctor. Therapists are already distinguishing between clinical symptoms, such as GRD: viral or bacterial. Wednesdays of the GRVI: influenza virus, parainfluenza, rhinovirus, reovirus etc. We have seen close to 200 GRVI weekdays. Only by laboratory methods can one prove that a person is ill with the influenza virus, etc. During the skin epidemic period, the 10th diagnosis of influenza is mild, while during the non-epidemic period, the number of infections decreases to 30-40%.

GRIP (from the French grippe - to spit, established by the doctor Sabazh in the 19th century). Synonymous with Italian influenza.

The viral nature of influenza was discovered in 1933. The English teachings Smith and the authors saw in patients with the GRZ virus. In our country, two prominent scientists, A. A. Smorodintsev and L. A. Zilber, discovered a different influenza virus in 1940, which evolved from the virus seen in 1933. In 1974, another influenza virus was discovered. There are currently 3 known flu viruses, which are designated A, B, C. All those uncured illnesses like the flu are associated with the influenza virus A. The influenza virus also periodically causes illness, but it is not as scary as epidemics and pandemics when the virus arises oh flu A.

Influenza A virus, inoculated to the submolecular level. All influenza viruses contain RNA; in the center of the virus particles there is a ribonucleoprotein, which consists of 8 fragments - 8 genes. 1-6 genes encode the synthesis of one protein, and 7-8 genes encode 2 proteins; The influenza virus genome encodes a total of 10 proteins. The RNP units are coated with a protein coat and are also coated with supercapsids. The supercapsid of the influenza virus is composed of a lipoprotein membrane, these cells in which the virus multiplies (the fragments come out of the cells in the way of bruning). It is important that different influenza A viruses multiply in different cells, their surfaces can become significantly irritated. Supercapsids have 2 proteins - enzymes. The stench is evoked from the appearance of thorns:

· Hemagglutinin 500-600 spikes. This enzyme can interact with the mucoprotein receptors of cells, so that the virus reacts with them and the virus is adsorbed on the surface of sensitive cells. Such receptors are on the surface of erythrocytes. The result of virus adsorption on erythrocytes is hemaglutination. Here is a method of indicating the virus: take blood and add a drop of radish to remove the virus: after 1.5 weeks there is aglutination. Since the virus must be titrated to the skin and add red blood cells to the skin, the strength of virus A is significant. : homologous antibodies bind to hemagglutinin and the galvanization reaction of the hemagglutin is avoided. It is clear that the influenza virus contains a number of hemagglutinin species. In human influenza viruses there are 4 antigenic types of hemagglutinin (designated H). The following antigenic variants are available: H1 (with antigenic variants 1,2,3), H2 (with antigenic variants 1,2,3) H3 (with antigenic variants 1,2,3).

· Neuraminidase between the spines of hemagglutinin. Neuraminidase is an enzyme that breaks down neuraminic acid, and is converted to the group of sialic acids, which are found in cell membranes. The role of neuraminidases is in mature cells, but does not help in penetration and exit from cells. Influenza viruses and humans have 2 antigenic variants of the neuraminidase type N1 N2.

The virus looks like a sea urchin - it is spherical, about 100 nm in diameter, covered with spikes.

Antigenic power to influenza A virus

Influenza viruses have a number of antigens: one antigen - the S-antigen, which is bound to the ribonucleoprotein, which is an internal antigen. After the S-antigen, the influenza virus is easily divided into influenza A, influenza B, and influenza C viruses. It is impossible to overlap the antigens here, since it is antigenic specificity. The assistant said that the influenza virus has a V-antigen, but in reality this is what they mean on the surface. : These include hemagglutinin and neuraminidase. These types of influenza virus include:

1. influenza A virus with H0N1 antigens

2. Influenza A virus with H1 N1 antigens. Appearing in 1947 rocі, having circulated 10 rocks (until 1957 rock), appeared on 20 rocks, again appearing in 1957 rocі and circulating dosi.

3. H2 N2 appeared in 1957 and circulated 10 years ago.

4. H3N2 appeared in 1968 and is circulating.

The H0N1 influenza virus was discovered in 1933, and circulated until 1947, and no one has been seen infected for 50 years.

Thus, influenza A virus, which causes illness at the same time, can be of two types. When this situation was explained, it became clear that the virus had been circulating ever since, having become an epidemic in 1957, because a new virus had appeared that was traced to two antigens and hemagglutinin and neuraminidase. It really was a pandemic: 2/3 of the Earth’s population fell ill. This virus was known, but in 1968 there was a new epidemic. There is a new virus that is being detected behind the H antigen. Thus, a pattern emerges: the emergence of a new virus is due to the formation of immunity in people. The more the new virus diversifies from the previous one, the more people get sick. This pattern provides a theoretical basis for action to prevent such illness from occurring.

Multiplicity of influenza virus A. Multiplicity of influenza virus is caused by two genetic processes:

Genetic shift occurs as a result of a new gene change and the exchange of genes during simultaneous reproduction of two influenza viruses in the community

· Antigenic drift - a change in the antigenic warehouse, without a new replacement of the antigen. In the middle of the antigen, minor changes occur. Antigenic drift is based on point mutations of the gene, as a result of a change in the antigen.

Types of infections. There are three types of infections:

· productive infection: the virus is adsorbed, penetrates, reproduces and exits. Klitina is in ruins. If this is present in the body, then serious illness occurs.

· Asymptomatic infection: reproduction rate is low. Clients suffer less and, on the whole, the body suffers from illness without symptoms, but when sick, there is an infection

· Latent infection: this type of infection has so far been studied in cell cultures in vitro. The origin of this type of infection in the human body is not known.

It appears after penetration of the virus that when RNP is formed, it attaches to the nucleus of the cell and thus resides in the cell. RNP is a foreign structure for the cell, and the compactness of the cell is conservative, so that it does not tolerate outsiders, but, prote, RNP seems to be in the middle of the cell. RNP is passed on to cell offspring. It is important that the 20-year failure of the virus is due to this mechanism itself.

INFLUENZA VIRUS: 2 influenza pandemics have been reported: first flu - Spanish flu at 18-20 r. XX century, pandemic in 1957. By this time, 20 million people had died from the flu. The influenza virus and the outbreak of GRZ will shorten the average troubles of life by about 10 years.

Flu is an anthroponosis. The influenza virus in humans is associated with illness in humans (it is also known that the influenza illness in humans is similar to the influenza illness in animals). The path of infection is wind-speckled. The virus is not stable in the global environment.

The gates of infection are the upper respiratory routes. Influenza viruses can spread to the prismatic epithelium of the upper respiratory tract. During reproduction, cells suffer from minor damage to cell necrosis. The rate of reproduction of the virus is even high and in 2-3 years the population of viruses increases by several orders of magnitude. This is why the incubation period for influenza is short. At the first stages of illness there are degenerative-dystrophic changes. There is no burning. If pneumonia develops in these early stages, it will again pass without a strong ignition reaction. Late bronchitis and pneumonia often develop with associated bacterial infection. As soon as sectional material of people who died from influenza pneumonia is examined, staphylococcus is then detected by microscopy, thus causing mixed infections.

SICKNESS WITH FLU:

· Intoxication: temperature 39-40, caused either by the viral particles or tricks to the virus. Significantly, the wall of the blood vessels changes due to increased penetration (hemorrhage); in the acute period, lazing is contraindicated.

· On the side of the central nervous system: for the shell of viral proteins, for the shell of neurotropic viruses.

MECHANISMS OF ANTI-VIRAL PROTECTION. Antibodies against antigens and enzymes of the virus play a major role in the fight against influenza. Immunity against stress flu, type-specific. Alpha beta and gama inhibitors - react with the active center of hemagglutinin and the virus cannot be adsorbed on tissue. The presence and potency of the inhibitor varies with the genotype of a person, being an individual characteristic. The offensive mechanism of protection is the interferon system. There are interferons alpha, beta and gama. Normally, there is no interferon in humans; interferon begins to be produced by the cell when it is either infected by a virus or stimulated by an inducer. The ability to produce interferon is also inherent in the human genotype.

LABORATORY DIAGNOSTICS.

There are three main methods:

· Express diagnostics: immunofluorescent method, ELISA. Immunofluorescence method: a polished slope is introduced into the patient’s nasal passage and a light scraper is applied. Then the glass is treated with luminescent serum and since there is a viral antigen in the cellulose, the antibodies are reactive with it and we add light.

· Virological. Take a specimen from the nasopharynx of a sick person and infect it smoking embryo After incubation, the presence of the virus is verified by the hemagglutination reaction, and the virus titer is determined by the hemagglutination galvanization reaction.

· serodiagnosis. The diagnostic criterion is an increase in antibody titer. This is a retrospective method.

CELEBRATION: one by one effective methods Treatment for influenza involves the use of anti-influenza syrups. These are the Chinese sirens that can be treated with hyperimmunization with influenza vaccine. Remove the syrup, lyophilize it, mix it with sulfonamide drugs and freeze it intranasally. An allergic reaction may be caused by anti-influenza gamma globulins. Interferon is administered intranasally, which is especially effective in the early stages of illness. Also use drugs that inhibit the reproduction of the virus: remantadine, riboverine, etc.

INFLUENZA PREVENTION: Academician Belyakov believes that the most important thing is vaccination. on Narazi It means:

· Live influenza vaccine (divided by Smorodintsev) is administered intranasally

· The vaccine is driven in - to take revenge on viruses infected with formaldehyde

· subviral vaccine that replaces hemagglutinin particles from viral particles.

· Synthetic vaccine, which is based on the synthesis of chemical hemagglutinin.

Microbiology 09.20.96.

Newsletters of ARVI (acute respiratory infections)

The gastrointestinal tract is rich in diseases: there are nearly 200 of them. Among them are prokaryotes: bacteria, mycoplasma, chlamydia. The diagnosis of acute respiratory viral infections is made by a doctor. Therapists are already distinguishing between clinical symptoms, such as GRD: viral or bacterial. Wednesdays of the GRVI: influenza virus, parainfluenza, rhinovirus, reovirus etc. We have seen close to 200 GRVI weekdays. Only by laboratory methods can one prove that a person is ill with the influenza virus, etc. During the skin epidemic period, the 10th diagnosis of influenza is mild, while during the non-epidemic period, the number of infections decreases to 30-40%.

GRIP (from the French grippe - to spit, established by the doctor Sabazh in the 19th century). Synonymous with Italian influenza.

The viral nature of influenza was discovered in 1933. The English teachings Smith and the authors saw in patients with the GRZ virus. In our country, two prominent scientists, A. A. Smorodintsev and L. A. Zilber, discovered a different influenza virus in 1940, which evolved from the virus seen in 1933. In 1974, another influenza virus was discovered. There are currently 3 known flu viruses, which are designated A, B, C. All those uncured illnesses like the flu are associated with the influenza virus A. The influenza virus also periodically causes illness, but it is not as scary as epidemics and pandemics when the virus arises oh flu A.

Influenza A virus, inoculated to the submolecular level. All influenza viruses contain RNA; in the center of the virus particles there is a ribonucleoprotein, which consists of 8 fragments - 8 genes. 1-6 genes encode the synthesis of one protein, and 7-8 genes encode 2 proteins; The influenza virus genome encodes a total of 10 proteins. The RNP units are coated with a protein coat and are also coated with supercapsids. The supercapsid of the influenza virus is composed of a lipoprotein membrane, these cells in which the virus multiplies (the fragments come out of the cells in the way of bruning). It is important that different influenza A viruses multiply in different cells, their surfaces can become significantly irritated. Supercapsids have 2 proteins - enzymes. The stench is evoked from the appearance of thorns:

· Hemagglutinin 500-600 spikes. This enzyme can interact with the mucoprotein receptors of cells, so that the virus reacts with them and the virus is adsorbed on the surface of sensitive cells. Such receptors are on the surface of erythrocytes. The result of virus adsorption on erythrocytes is hemaglutination. Here is a method of indicating the virus: take blood and add a drop of radish to remove the virus: after 1.5 weeks there is aglutination. Since the virus must be titrated to the skin and add red blood cells to the skin, the strength of virus A is significant. : homologous antibodies bind to hemagglutinin and the galvanization reaction of the hemagglutin is avoided. It is clear that the influenza virus contains a number of hemagglutinin species. In human influenza viruses there are 4 antigenic types of hemagglutinin (designated H). The following antigenic variants are available: H1 (with antigenic variants 1,2,3), H2 (with antigenic variants 1,2,3) H3 (with antigenic variants 1,2,3).

· Neuraminidase between the spines of hemagglutinin. Neuraminidase is an enzyme that breaks down neuraminic acid, and is converted to the group of sialic acids, which are found in cell membranes. The role of neuraminidases is in mature cells, but does not help in penetration and exit from cells. Influenza viruses and humans have 2 antigenic variants of the neuraminidase type N1 N2.

The virus looks like a sea urchin - it is spherical, about 100 nm in diameter, covered with spikes.

Antigenic power to influenza A virus

Influenza viruses have a number of antigens: one antigen - the S-antigen, which is bound to the ribonucleoprotein, which is an internal antigen. After the S-antigen, the influenza virus is easily divided into influenza A, influenza B, and influenza C viruses. It is impossible to overlap the antigens here, since it is antigenic specificity. The assistant said that the influenza virus has a V-antigen, but in reality this is what they mean on the surface. : These include hemagglutinin and neuraminidase. These types of influenza virus include:

1. influenza A virus with H0N1 antigens

2. Influenza A virus with H1 N1 antigens. Appearing in 1947 rocі, having circulated 10 rocks (until 1957 rock), appeared on 20 rocks, again appearing in 1957 rocі and circulating dosi.

3. H2 N2 appeared in 1957 and circulated 10 years ago.

4. H3N2 appeared in 1968 and is circulating.

The H0N1 influenza virus was discovered in 1933, and circulated until 1947, and no one has been seen infected for 50 years.

Thus, influenza A virus, which causes illness at the same time, can be of two types. When this situation was explained, it became clear that the virus had been circulating ever since, having become an epidemic in 1957, because a new virus had appeared that was traced to two antigens and hemagglutinin and neuraminidase. It really was a pandemic: 2/3 of the Earth’s population fell ill. This virus was known, but in 1968 there was a new epidemic. There is a new virus that is being detected behind the H antigen. Thus, a pattern emerges: the emergence of a new virus is due to the formation of immunity in people. The more the new virus diversifies from the previous one, the more people get sick. This pattern provides a theoretical basis for action to prevent such illness from occurring.

Multiplicity of influenza virus A. Multiplicity of influenza virus is caused by two genetic processes:

Genetic shift occurs as a result of a new gene change and the exchange of genes during simultaneous reproduction of two influenza viruses in the community

· Antigenic drift - a change in the antigenic warehouse, without a new replacement of the antigen. In the middle of the antigen, minor changes occur. Antigenic drift is based on point mutations of the gene, as a result of a change in the antigen.

Types of infections. There are three types of infections:

· productive infection: the virus is adsorbed, penetrates, reproduces and exits. Klitina is in ruins. If this is present in the body, then serious illness occurs.

· Asymptomatic infection: reproduction rate is low. Clients suffer less and, on the whole, the body suffers from illness without symptoms, but when sick, there is an infection

· Latent infection: this type of infection has so far been studied in cell cultures in vitro. The origin of this type of infection in the human body is not known.

It appears after penetration of the virus that when RNP is formed, it attaches to the nucleus of the cell and thus resides in the cell. RNP is a foreign structure for the cell, and the compactness of the cell is conservative, so that it does not tolerate outsiders, but, prote, RNP seems to be in the middle of the cell. RNP is passed on to cell offspring. It is important that the 20-year failure of the virus is due to this mechanism itself.

INFLUENZA VIRUS: 2 influenza pandemics have been reported: first flu - Spanish flu at 18-20 r. XX century, pandemic in 1957. By this time, 20 million people had died from the flu. The influenza virus and the outbreak of GRZ will shorten the average troubles of life by about 10 years.

Flu is an anthroponosis. The influenza virus in humans is associated with illness in humans (it is also known that the influenza illness in humans is similar to the influenza illness in animals). The path of infection is wind-speckled. The virus is not stable in the global environment.

The gates of infection are the upper respiratory routes. Influenza viruses can spread to the prismatic epithelium of the upper respiratory tract. During reproduction, cells suffer from minor damage to cell necrosis. The rate of reproduction of the virus is even high and in 2-3 years the population of viruses increases by several orders of magnitude. This is why the incubation period for influenza is short. At the first stages of illness there are degenerative-dystrophic changes. There is no burning. If pneumonia develops in these early stages, it will again pass without a strong ignition reaction. Late bronchitis and pneumonia often develop with associated bacterial infection. As soon as sectional material of people who died from influenza pneumonia is examined, staphylococcus is then detected by microscopy, thus causing mixed infections.

SICKNESS WITH FLU:

· intoxication: temperature 39-40, caused either by the viral particles themselves or by the tricks of the virus. Significantly, the wall of the blood vessels changes due to increased penetration (hemorrhage); in the acute period, lazing is contraindicated.

· On the side of the central nervous system: for the shell of viral proteins, for the shell of neurotropic viruses.

MECHANISMS OF ANTI-VIRAL PROTECTION. Antibodies against antigens and enzymes of the virus play a major role in the fight against influenza. Immunity against stress flu, type-specific. Alpha beta and gama inhibitors - react with the active center of hemagglutinin and the virus cannot be adsorbed on tissue. The presence and potency of the inhibitor varies with the genotype of a person, being an individual characteristic. The offensive mechanism of protection is the interferon system. There are interferons alpha, beta and gama. Normally, there is no interferon in humans; interferon begins to be produced by the cell when it is either infected by a virus or stimulated by an inducer. The ability to produce interferon is also inherent in the human genotype.

LABORATORY DIAGNOSTICS.

There are three main methods:

· Express diagnostics: immunofluorescent method, ELISA. Immunofluorescence method: a polished slope is introduced into the patient’s nasal passage and a light scraper is applied. Then the glass is treated with luminescent serum and since there is a viral antigen in the cellulose, the antibodies are reactive with it and we add light.

· Virological. Take a swab from the patient’s nasopharynx, infect a chicken embryo, after incubation the presence of the virus is checked by the hemagglutination reaction, the titer of the virus is determined by the galvanization reaction of hemagglutination.

Taxonomy and classification: RNA viruses. Family I - Paramyxoviridae includes human parainfluenza viruses (5 serotypes) and respiratory syncytosis virus (RS);

Family II - Picomaviridae includes 7 serotypes of enteroviruses Coxsackie and ECHO, which attack diaphragmatic viruses, and 120 serotypes of rhinoviruses;

Family III – Reoviridae includes 3 serotypes that cause illness in the respiratory and scolio-intestinal tracts;

Family IV - Coronaviridae includes 3 serotypes that also attack the respiratory and scolial-intestinal tracts.

Structure : Medium size, spherical, rod-like or thread-like shape. Most of the GRV viruses contain single-stranded RNA, except for reoviruses, which contain double-stranded RNA, and DNA adenoviruses. The veins of them are lined with supercapsid.

Antigenic structure : foldable The skin virus has antigens; Viruses also contain type-specific antigens, which can be used to identify individuals from the assigned serotype. The skin group of HRV viruses includes a variety of serotypes and serovars. Most HRV viruses are hemagglutinous. RTGA is based on blocking the activity of hemagglutinin viruses by specific antibodies.

Culture : Optimal model for the cultivation of cells. For the skin group of viruses, the most sensitive cells are selected (for adenoviruses - fetal cells; for coronaviruses - fetal cells and tracheal cells). In infected cells the virus causes CPE (cytopathic effect). Cellin cultures are also tested when identifying pathogens with cytolytic activity (for example, adenoviruses). This is why the so-called reaction of biological neutralization of viruses in a cell culture (RBN and RN of viruses) is called for. It is based on the neutralization of the cytolytic activity of viruses with type-specific antibodies.

Immunity: virus-neutralizing specific IgA (to ensure local immunity) and Cellular immunity. Local production of a-interferon, which appears in the nasal passages, can lead to a significant reduction in the number of viruses. An important feature of HRV is the formation of secondary immunodeficiency. Post-infectious immunity is unstable, unbreakable, type-specific. There is a great number of serotypes and diversity of viruses – high frequency relapse.

Microbiological diagnostics Material for examination of nasopharyngeal mucus, swabs and swabs from the throat and nose.


Express diagnostics. Detect viral antigens in infected cells. Use RIF (direct and indirect methods) with fluorochrome-labeled specific antibodies, as well as ELISA. For viruses that need to be cultivated, the genetic method (GMT) is used.

Virological method. Indication of viruses in infected laboratory models is carried out by CPE, as well as by RGA and hemadsorption (for viruses with hemagglutinous activity), by inclusion (internal nuclear inclusions during adenovirus infection, cytoplasmic not included in the navcolonuclear zone during revirus). for illumination of “plaques”, and “color test”. Identify viruses by the antigenic structure of RSK, RPGA, ELISA, RTGA, RBN viruses.

Serological method. Antiviral antibodies were monitored in sick siblings captured at intervals of 10 days. The diagnosis should be made based on an increased antibody titer at least 4 times. Which shows the level of IgG in reactions such as RBN viruses, RSK, RPGA, RTGA.

Likuvannya : effective etiotropic - no; non-specific - a-interferon, oxolin (eye drops), for a second bacterial infection - antibiotics. The main treatment is symptomatic/pathogenetic. Antihistamines.

Prevention: non-specific - anti-epidemic. podіi. Specific – no. For the prevention of adenoviruses - oral live trivalent vaccines.

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