Causes, symptoms and influenza treatment. Flu is the most dangerous rally viral flu than treat

Influenza is infection Upper respiratory tract. Caused by the influenza virus and can take the dimensions of epidemics (from 5% of the fallen inhabitants) and pandemic (distribution to neighboring countries).

The flu virus is steady in the cold season, about 15% of the inhabitants of the Earth each year. Children, pregnant women, elderly and people suffering from heart disease and lungs are particularly vulnerable.

Study history

The flu virus people were sick for a long time. Back in 412 to n. e. Hippocrates recorded a case of the disease, along the symptoms very similar to the influenza virus. In the Middle Ages, people often hurt the flu, often the situation took the character of the epidemic. Since the beginning of the XII century, more than a hundred cases of the dissemination of the disease have been recorded in the sources. A real disaster was a pandemic in 1580, when many people in Europe died. Of course, in those days people did not have the idea what a virus is, and the mass morbidity of people attributed to the kare of the gods or the fluttering comet.

IN XX century The most famous pandemic - Spanish flu (Spanish) - raged in 1918, 30% of the world's population were infected, about 100 million people were killed. Interestingly, China was a hearth of this virus. Then, where are Spain? The fact is that in those years (and these were the years of the First World War) The country of Spain did not participate in hostilities, the censorship in the media was minimal, and the reporters loosely covered the events, including cases of influenza. The newspapers constantly flashed messages about mass infection and high mortality, so the general idea was to have developed that in Spain became the place of spread of the virus.

The viral nature of the influenza was opened only in the 30s of the twentieth century. In 1931, the American scientist R. Shoop was put forward to the assumption that the disease in the pigs he studied is very similar to the symptoms of influenza and has a viral origin. In 1933, this assumption was confirmed: indeed, it was possible to allocate a microorganism called Orthomixovirus Influenzae - the virus of influenza A. In the 40s, viruses of types B and C were identified

Currently, all these types are well studied, as well as their symptoms. A-type influenza is the most dangerous. He constantly mutters and amazes people and animals. Viruses in and with multiply only in the human body.

What the virus looks like

In every way the flu is often called any kind of sharp respiratory diseases. But do not confuse the influenza virus with other ARVI viruses, which revealed more than 200 species.

What does the flu virus look like? The causes of influenza are microorganisms containing RNA or DNA. Exist and multiply in environment They cannot, so they are being introduced into the organisms of living beings. Finding into the upper airwaysThe virus sticks to the cells of the mucous membranes, comes to life and begins to actively share.

At that moment, the sick is very contagious, since the virus is sprinkled with coughing and sneezing to many meters around and falls into the respiratory tract of other people or animals. It has been proven that the virus applies at a speed of 120 km / h.

Equator is considered an equator, the outbreaks of the disease are registered regularly. It is believed that the virus lives in the organisms of birds and animals, during the migration of flight birds, flu viruses move to other parts of the world.

Infection

All people are susceptible to the influenza virus. The disease is distributed by air-drip, the source of infection is a sick man with obvious or only beginners of influenza. The smallest droplets of saliva and mucus when coughing and sneezing are spreading to many meters around, they inhale others.

With the uncomplicated course of the disease, the selection of the virus is terminated for about 6 days, with complications in the form of pneumonia, a person remains contagious to 3 weeks.

The virus is perfectly preserved at minus temperatures, so flash outbreaks occur during the cold season. Every 2-3 years there is an epidemic when up to 50% of the population may be sowed. Usually the epidemic causes the type A virus, since this type is the most susceptible to mutations. The symptoms of the A-type influenza are familiar to almost everyone. Below we clarify this information again.

The type V virus applies significantly slower and covers about 25% of people every 4-6 years. The type C virus amazes mostly children and highly weakened people.

The most favorable temperature for the spread of the influenza virus is the range from -5º to + 5º. At these temperatures, the humidity of the air decreases, the respiratory tract of the person becomes more dry, and the virus freely enters the body.

Basic symptoms

Symptoms of the disease usually appear suddenly. There are several degrees of the course of the disease, but we will talk about it later.

The incubation period (the period from the virus hitting the body before the appearance of the first symptoms) is about 2 days.

Flu began to begin as follows:

• A sharp rise in temperature - up to 38º and above.
• Strong chills.
• Total weakness and malaise.
• Lomotics in the bones and pain in the muscles are signs of intoxication of the body.
• Noye headache. It applies to the entire forehead, whiskey, on the abnormal arcs and a soccer. The elderly pain can cover the whole head, neck and shoulders.
• Pain and thread in the eyes, especially when rotating the eyes.
• Toothing, conjunctivitis.
• Sensitivity to light, sharp sounds.
• Increased sweating.
• Red face, but the skin of the body is pale.
• In severe forms, nausea, vomiting, diarrhea (intestinal flu) can begin.
• Young children can be cramps.
• Willing sleep, anxiety, hallucinations.
• Nasal congestion, error and dry throat. However, these catarrhal symptoms quickly pass, and a strong dry cough begins. It can last 7-10 days.
• Redness in the throat gradually acquires a blue tint, the edema develops. After a week, the mucosa is restored.
• Convenience and dryness in nasal passages is replaced by a strong runny nose. The mucus can constantly flow from the nose, while the bridge is hurting. Possible nasal bleeding due to strong highs.
• When listening to lungs, short-term lags are heard. When coughing begins to hurt the chest, cough painful and adsatory cough. Possible complications in the form of bronchitis and tracheitis.

Children are possible, the defeat of the larynx and other organs respiratory system. There is an echo of larynx and trachea, rapid and difficult breathing, an adsatory long cough.

• The influenza virus can hit the heart muscle. In this case, when listening to the heart, the doctor will hear the muffled sound, a rhythm.
• At the beginning of the disease, the pulse is frequent. Three days later, the pulse slows down, the general weakness appears.
• Lost, decline in appetite, rejection of food. As a result, the intestinal peristalsis deteriorates, constipation and bloating are possible. In the language there are white raids.
• When complicating on the kidney, there is a change in current indicators in the composition of urine. It appears protein and red blood cells.
• In the blood, the number of leukocytes increases, elaborates ERAC (erythrocyte sedimentation rate).
• Fever lasts from two to 10 days. Feeling all the time feels fatigue and defeat. He is tormented by a runny nose, cough, lubrication in the body and heat. After a disease, many observed irritability, drowsiness, reduced blood pressure, asthenia. In this case, the recovery period is needed.

Degree of disease

The flu itself, his symptoms and treatment are very similar to ORVI, so externally determine the presence of influenza is difficult. However, with a mass disease, you can talk about the epidemic, and this indicates the influenza virus.

The severity of the disease may be different:

• The light shape of the influenza is very weak, the temperature rises slightly, there are practically no symptoms.
• The average severity of the disease is characterized by an increase in temperature to 38º - 39º; Typical influenza symptoms are observed: lubrication, weakness, headache, dryness and sore throat, cough begins.
• A heavy form involves an increase in temperature to 40º, seizures, hallucinations, vomiting, nasal bleeding begins.
• Heavy hyperstoxic shape. With this form in a patient, the temperature is above 40º, serious disorders in the work of the brain and the nervous system are noted. Bleeding, brain edema and lungs are possible. High probability of fatal outcome.

What is dangerous flu dangerous

First of all, the flu is dangerous by various complications. Especially often complications are developing in children, elderly and weakened people.

Heavy influenza forms are able to make health maximum harm. Distinguish 2 basic types of complications:

1. Light complications. These can be various pneumonia, light abscess, sharp respiratory syndromes.
2. Extreme complications. This rhinitis, sinusitis, otitis, tracheitis, meningitis, encephalitis, radiculonurite, myocarditis, liver and kidney damage.

Especially carefully needed to treat the course of the disease in children under 3 years and to people over 65 years old. This is the most dangerous age in which the body's protective functions are weakened, therefore high risk of complications.

Treatment and prevention

Influenza - serious and cunning disease, Doctors doctors independently treat him. At first signs of the disease, immediately consult a doctor and make a diagnosis. Element the influenza virus is possible using nasal and throat smears. For more accurate diagnosis, the doctor may assign a patient to pass general analysis blood and make x-ray lungs.

• A sick person should be selected in a separate room, put in bed and highlight for it lingerie, towel, dishes, hygiene objects (including soap). Remember that the virus lives in the environment until 72 hours, and the patient is 7-10 days.
• Wear a gauze bandage and try not to communicate with coughing and sneezing people. In the days of the epidemic, do not attend mass events and contact less with other people.
• At the first signs of the disease, there should be at home and avoid contacts with relatives and other people. Call your doctor at home.
• Regularly ventilate all the rooms, do twice a day wet cleaning.
• We wash your hands more often, clean the nose and cozy the throat. Do not touch the dirty hands to the nose, eye, mouth.
• Drink enough water (2-2.5 liters of water per day).
• Increase immunity with simple and accessible ways. To do this, it is useful to drink infusion of Echinacea, the decoction of richness, there are sour berries (cranberries, lingonberry) more citrus fruits. It is proved that Vitamin C warns the risk of infection several times, and at the very beginning of the disease - greatly facilitates the symptoms and the course of the disease.
• Correctly fitter. Give preference to healthy vegetable food in which there are many vitamins and trace elements.
• Make morning gymnastics, engage in active sports. Very useful walking in the rapid pace. Try at least 30 minutes a day to actively spend time.
• Observe the day mode. Alternate and rest, let yourself be saturated. Scientists have proven that regular lack of sleep (sleep less than 6 hours) oppresses immunity. Full sleep, on the contrary, is able to significantly increase the body's resistance to viruses and bacteria.
• Avoid stress, they significantly weaken the organism.
• What should not do absolutely - it's smoking. It is proved that smoking weakens the body and suppresses natural immunity. In case of flu, smoking is completely contraindicated, as the virus is striking the trachea, bronchi and lungs, these organs will simply do not hold out Nicotin attack.

Many people have a manifestation of influenza. Symptoms are very reminded by a cold. However, the flu is not an easy, it is fraught with serious complications. Therefore, conduct prevention, follow the rules for communicating with sick people and be sure to consult a doctor.

These viruses are only distantly associated with human paragrippa viruses, which are RNA viruses belonging to the family of paramixes that are frequent cause respiratory infections In children, such as croup, but can also cause a disease similar to the flu, in adults. The fourth family of influenza viruses - influenza D. The type of type of this family is a large cattle influenza virus, which was first highlighted in 2012.

Influenzavirus A.

This genus has one kind, influenza virus A. Wild etched birds are natural owners for a wide variety of influenza viruses A. Sometimes viruses are transmitted to other species, and then can lead to destructive outbreaks among the poultry or lead to influenza pandemic in humans. Type A viruses are the most vigilant human pathogens among the three types of influenza and can cause severe disease. Flu viruses type A can be divided into various serotypes based on antibody response to these viruses. Serotypes that were confirmed in the human body ordered by the number of human deaths as a result of a pandemic:

H1N1, which caused Spanish in 1918 and swine flu in 2009

H2N2, which caused Asian flu in 1957

H3N2, which caused Hong Kong flu in 1968

H5N1, which caused a bird flu in 2004

H7N7, which has an unusual zoonogenic potential

H1N2, endemic among people, pigs and birds

Influenzavirus B.

Influenza B almost exclusively infects people and meets less often than influenza A. Single animals, except for a person susceptible to infection of influenza type B - seal and ferret. This type of flu is mutated at a speed of 2-3 times slower than type A and, therefore, less genetically diverse. There is only one flu influenza B. As a result, the lack of antigenic diversity, the degree of immunity to the influenza B is usually purchased in early age. However, influenza b mutters quite often, and permanent immunity is not possible. This reduced antigenic change rate, in combination with a limited circle of hosts (inhibits an antigenic shift between the species), is a guarantee that flu pandemic in will not occur.

Influenzavirus C.

This genus has one kind, the flu virus with, which infects people, dogs and pigs, sometimes causing severe diseases and local epidemics. However, the flu is less common than other types of influenza, and usually causes only a slight disease in children.

Structure, properties and nomenclature of subtypes

Flu viruses A, B and C are very similar in their structure. The particle of the virus is 80-120 nm in diameter and, as a rule, has an approximately spherical shape, although filamentous forms may occur. These filamentine forms are more common in flu with a pomp, which can form a rope structure up to 500 μm long on the surface of infected cells. However, despite these diverse forms, viral particles of all influenza viruses are similar in their composition. Viral particles consist of a shell containing two main types of glycoproteins wrapped around the central kernel. The central kernel contains a viral RNA genome, and other viral proteins are sealing and protecting this RNA. RNA is usually single-chain, but in special cases double. What is unusual for the virus, its genome is not one fragment of nucleic acid. Instead, it contains seven or eight parts of segmented negatively polar RNA, while each part of RNA contains one or two genes that encode the gene product (protein). For example, the genome of the influenza A contains 11 genes on eight parts of RNA encoding 11 proteins: hemagglutinin (HA), neuraminidase (NA), nucleoproteid (NP), M1, M2, NS1, NS2 (NEP: nuclear export protein), PA, PB1 (polymerase base 1), Pb1 -f2 and Pb2. Hemagglutinin (HA) and neuraminidase (Na) are two large glycoproteins on the outer side of viral particles. On is a lectin, which mediates the binding of the virus with target cells and penetration of the viral genome into the target cell, while Na participates in the release of the posterity of the virus from infected cells, when the sugars are cleaving, which bind mature viral particles. Thus, these proteins are a target for antiviral drugs. In addition, they are antigens to which antibodies can be excited. Influenza viruses are divided into subtypes based on the reaction of antibodies on on and Na. These different types of HA and Na form the basis of differences in H and N, for example, the H5N1 virus. There are 16 subtypes H and 9 subtypes N, but only H 1, 2 and 3, and N 1 and 2 are usually found in the human body.

Replication

Viruses can only be replicated in living cells. Infection and replication is a multi-stage process: first, the virus should contact the cell and enter it, then deliver its genome to the area where it can produce new copies of viral proteins and RNA, collect these components into new viral particles, and Finally leave the host cell. Influenza viruses are binding to hemagglutinin on Salahic acid sugars on the surface of epithelial cells, as a rule, in the nose, throat and light mammals and in the intestine of birds. After the hemagglutinin is split off the protease, the cell imports the virus by endocytosis. Intracellular parts are still clarified. It is known that the virions converge to microtubule, organizing the center, interact with acid endosomes and, finally, penetrate the target endosomes for the release of the genome. Once inside the cell, the acidic medium in the endosome causes two events: first, part of the hemagglutinin protein glorifies a viral shell with a vacuum membrane, then the ion channel M2 allows the protons to move along the viral shell and oxidize the virus core, which causes the separation of the kernel and the release of viral RNA and kernel proteins. Viral RNA molecules (VRNA), auxiliary proteins and RNA-dependent RNA polymerase are then emitted to the cytoplasm (2nd stage). The ion channel M2 is blocked by the drug amantadine, which prevents the development of infection. These main proteins and VRNA form a complex that is transported to the cell core, where RNA-dependent RNA polymerase begins to transcribe an additional positive-polar VRNA (steps 3a and b). VRNA is either exported to the cytoplasm and is broadcast (step 4) or remains in the kernel. The newly synthesized viral proteins are either secreted through the Golgi apparatus on the cell surface (in the case of neuraminidase and hemagglutinin, step 5b) or transported back to the kernel to associate a VRNA and form new particles of the viral genome (step 5a). Other viral proteins have several actions on the host cell, including deteriorating cell mRNA and using elevated nucleotides for the synthesis of VRNA, as well as inhibiting the broadcast of MRNA host cells. Negative-polar VRNAs that form the genomes of future viruses, RNA-dependent RNA polymerase and other viral proteins are collected in the virion. Gemagglutinin and neuraminidase molecules are grouped into convexity in the cell membrane. VRNA and the core virus proteins leave the kernel and enter this branch (step 6). Mature viral kidneys leave the cell and move in the sphere of phospholipids of the host membrane, which gives hemagglutinin and neuraminidase is a membrane coating (step 7). As before, the viruses adhere to cells through hemagglutinin. Mature viruses are separated from the cell, as soon as their neuraminidase splits the remains of sialic acid from the host cell. After the release of new influenza viruses, the host cell dies. Due to the lack of RNA corrective enzymes, RNA-dependent RNA polymerase, which copies the viral genome, makes an error of about every 10 thousand nucleotides, which is approximately the length of the HRNA influenza. Consequently, the majority of the newly manufactured influenza viruses are mutant; This causes an antigen drift, which is a slow change in antigens on the virus surface for a long time. The separation of the genome on eight separate VRNA segments allows you to mix or unimpose VRNA, if more than one type of influenza virus infects one cell. Observed as a result, the rapid change in viral genetics produces antigenic shifts, which are sharp changes from one antigen to another. These sudden big changes allow the virus to infect a new owner and quickly overcome protective immunity. This is important when a pandemic occurs.

Mechanism

Transmission

When an infected person sneezes or coughs, more than half a million virus particles can spread to people nearby. In healthy adults, the spread of the influenza virus (the time during which a person can be infectious) sharply increases half the day after infection, the peak comes to the 2nd day and is preserved for, on average, five days, but can be maintained nine days. For those people who develop symptoms from experimental infection (only 67% of healthy experimentally infected individuals), symptoms and virusing show a similar picture, but the virusing precedes the disease for one day. Children are much more contagious than adults, and distribute the virus from the moment of the development of symptoms and up to two weeks after infection. People with weakened immunity, the selection of the virus can last longer than two weeks. The flu can spread in three main ways: by direct transmission (when an infected man sneezes, and the sputum falls directly into the eyes, nose or mouth of another person); airborne droplet (when someone inhales the air infected with man with a cough or sneezing), and through hands in the eyes, through hands in the nose, or through hands in the mouth, or through contaminated surfaces, or through direct personal contact (for example, Sharp your hand). The relative importance of these three ways to transfer remains unclear, and they can all facilitate the spread of the virus. With air-drip transmission, drops are sufficiently small for inhalation by man, from 0.5 to 5 μm in diameter. Inhalation only one drop can be enough to cause infection. Despite the fact that over one sneezing is standing out to 40,000 drops, most of the drops are large enough and quickly settle. How long the flu survives in air drops, it seems depends on the level of moisture and UV radiation, while the low humidity and the lack of sunlight in the winter period contribute to survival. Since the flu virus can persist outside the body, it can also be transmitted through contaminated surfaces, such as banknotes, door handles, light switches and other household items. The duration of time during which the virus will persist on the surface varies. The virus survives for one or two days on solid non-porous surfaces, such as plastic or metal, for fifteen minutes on dry paper napkins, and only for five minutes on the skin. However, if the virus is present in the mucus, it can protect it for longer periods (up to 17 days on banknotes). Viruses bird flu Can survive for an indefinite period when freezing. They are inactivated when heated to 56 ° C (133 ° F) for at least 60 minutes, as well as with the help of acid (at pH<2).

Pathophysiology

Mechanisms with which the influenza infection causes symptoms in people, studied intensively. One of the mechanisms as believed is to inhibit the adrenocorticotropic hormone (ACTH), which leads to a decrease in the level of cortisol. Knowledge of what genes are transferred to a specific strain can help predict how much it will infect people and how serious infection will be (that is, to predict the pathophysiology of the strain). For example, part of the process that allows influenza viruses to penetrate the cells, is the splitting of a viral protein of hemagglutinin by any human protease. In the case of light and airlet viruses, the structure of hemaggglutinin means that it can only be split only by proteases that are in the throat and lungs, so these viruses cannot infect other fabrics. Nevertheless, in the case of highly virulent strains, such as H5N1, hemagglutinin can be split by a wide variety of proteases, which allows the virus to spread throughout the body. The hemagglutinin viral protein is responsible for determining which types of strain can infect, and where the flu strain will be born in the respiratory tract of man. Stranches that are easily transmitted between people have hemagglutinine proteins that bind to receptors at the top of the respiratory tract, for example, in the nose, throat and mouth. In contrast, the H5N1 deadly strain is associated with receptors, which are mainly deep in the lungs. This difference in the infection site can be one of the reasons why the H5N1 strain causes severe viral pneumonia in the lungs, but not so easily transmitted by people when coughing and sneezing. Common influenza symptoms, such as fever, headaches and fatigue, are the result of the presence of a huge number of pro-inflammatory cytokines and chemokines (for example, interferon or tumor necrosis factor) in infected cells. Unlike rinovirus, which causes a cold, the flu causes tissue damage, therefore the symptoms are not fully associated with an inflammatory response. This powerful immune response can produce hypercitelinemia. Presumably, this effect may be the cause of an unusual mortality of the H5N1 avian influenza virus and a pandemic strain of 1918. Nevertheless, another possibility is that these large quantities of cytokines are only the result of massive levels of viral replication produced by these strains, and the immune response itself does not contribute to the disease.

Prevention

Graft

Flu vaccine is recommended by the World Health Organization Centers and Centers for the Control and Prevention of United States Diseases among high-risk groups, such as children, elderly, medical workers, as well as people who have chronic diseases, such as asthma, diabetes, cardiovascular Vascular diseases, or persons with weakened immunity. In healthy adults, the vaccine is moderately effective in reducing the number of flu-like symptoms in the population. Actual data maintain a decrease in influenza rates in children over two years. In people with chronic obstructive pulmonary disease, vaccination reduces the number of exacerbations, but it is not clear whether it reduces the number of exacerbations from asthma. Evidence maintain a lower level of flu-like diseases in many groups with immunosuppression, such as patients with HIV / AIDS, cancer, and after organ transplantation. People with a high risk, immunization can reduce the risk of cardiovascular diseases. It is unclear whether immunization of health workers affects treatment results. Due to the high speed of the virus mutation, a particular flu vaccine, as a rule, provides protection for no more than a few years. Each year, the World Health Organization predicts which virus strains are likely to be circulated next year, which allows pharmaceutical companies to develop vaccines that will ensure the best immunity against these strains. The vaccine will be reformulated every season on several specific flu strains, but does not include all strains active in the world during this season. The development and production of millions of doses necessary to combat seasonal epidemics takes about six months; From time to time, a new or overwhelming strain becomes noticeable during this time. In addition, it can be infected immediately before vaccination, as well as sick strain, which is vaccine, presumably should prevent, because in order for the vaccine to become effective, it is necessary about two weeks. Vaccines can cause a reaction of the immune system as if the body would actually be infected, and common symptoms of infection can develop (many symptoms of colds and influenza are only common symptoms of infection), although these symptoms are usually not so serious and durable like influenza. The most dangerous side effect is a strong allergic reaction or a viral material itself, or to residues from chicken eggs used to grow influenza; Nevertheless, these reactions are extremely rare. The economic efficiency of vaccination against seasonal influenza was widely appreciated for various population groups and in various situations. It was established that vaccination is cost-effective, especially in children and the elderly, but the results of economic evaluations of flu vaccination against influenza are often dependent on key assumptions.

Prevention of influenza

Reasonably effective methods of reducing the transmission of influenza include good personal hygiene and habit not touch the eyes, nose or mouth; Frequent washing of hands (with soap and water, or alcohol outflows for washing hands); habit of close the mouth when coughing and sneezing; Avoid close contact with sick people; And understanding the need to stay at home if you are sick. It is also recommended to avoid spit. Despite the fact that facial masks can help prevent transmission during patient care, there are mixed data on the beneficial effects of these masks in society. Smoking increases the risk of influenza infection, and also produces more serious symptoms of the disease. Since the flu is applied by air-droplet and, when contacting infected surfaces, surface disinfection can help prevent some infections. Alcohol is an effective disinfectant against influenza viruses. Quaternary ammonium compounds can be used along with alcohol, due to which the disinfecting effect lasts longer. In hospitals, quaternary ammonium and chlorine compounds are used for disinfection of premises or equipment that were occupied by patients with influenza symptoms. At home, this can be effectively done by adding a chlorine-containing bleach. During past pandemic, the closure of schools, churches and theaters slowed down the spread of the virus, but did not have a great effect on the overall level of mortality. It is unclear whether the abbreviation of mass clusters of the people, for example, by closing schools and jobs, effective in reducing the spread of influenza, as individuals with influenza, you can simply move from one place to another; Such measures will also be difficult to implement in practice and it may be unpopular. When a small number of people is infected, the insulation of patients can reduce the risk of transmission.

Physic treatment

People sick with flu are recommended to rest much, drink plenty of liquid, avoid drinking alcohol and tobacco, and, if necessary, take medicines, such as acetaminophen (paracetamol) to reduce the fever and muscle pain associated with the influenza. Children and adolescents with influenza symptoms (especially fever) should be avoided by aspirin during infection (especially influenza type B influenza), as this may lead to the development of the Reee syndrome, rare, but potentially fatal liver disease. Since the flu is caused by a virus, antibiotics do not affect infection; If they are not prescribed for the treatment of secondary infections, such as bacterial pneumonia. Antiviral drugs can be effective if they are accepted in early terms, but some flu strains may have resistance to standard antiviral drugs and there is concern about the quality of studies.

Antiviral tools

Two classes of antiviral drugs used against influenza - neuraminidase inhibitors (oseltamivir and zanamivir) and protein inhibitors M2 (adamantane derivatives).

Neuraminidase inhibitors

In general, the advantages of neuraminidase inhibitors in healthy people seem to not exceed risks. There is no use of these drugs in people with other health problems. Among patients considered patients with influenza, these drugs reduce the duration of symptoms on a little less than one day, but, apparently, do not affect the risk of complications, such as the need for hospitalization or risk of pneumonia. Until 2013, the benefit was not established, since the manufacturer (ROCHE) refused to provide test data for independent analysis. More common resistance to neuraminidase inhibitors has led researchers to search for alternative antiviral drugs with various mechanisms of action.

Inhibitors M2.

Antiviral drugs Amantadine and Rimantadine inhibit the viral ion channel (protein M2), thus inhibiting the replication of influenza A. Virus A. These drugs are sometimes effective against flu, if they are given at the beginning of infection, but ineffective against influenza viruses in which there is no target of drugs M2 . The measured resistance of Amantadin and Rimantadina in American H3N2 isolates increased to 91% in 2005. Such a high level of resistance can be associated with the easy accessibility of amantadine as part of the non-receptible medium of colds in countries such as China and Russia, and their use to prevent flashes of flu in the farm bird. CDC has not recommended the use of M2 inhibitors during flu 2005-06. Due to the high level of resistance to drugs.

Forecast

The influenza virus effects are much more serious and last longer than the usual cold. Most people are fully recovered in 1-2 weeks, but others may develop the life-threatening complications (for example, pneumonia). Thus, the flu may be deadly, especially for weak, young and old, or in chronically sick. People with a weak immune system, for example, people with an advanced stage of HIV infection or patients with transplantation (whose immune system is suppressed to avoid rehabilitation of the transplanted organ) suffer from particularly severe disease. Pregnant women and small children are also exposed to an increased risk of complications. Influenza can aggravate chronic health problems. People with emphysema, chronic bronchitis or asthma can develop shortness of breath during flu, and the flu can cause an aggravation of coronary heart disease or stagnant heart failure. Smoking is another risk factor associated with a more serious disease and increase in influenza mortality. According to the World Health Organization, "every winter dozens of millions of people are ill with influenza. Most of them are not present at the workplace only during the week, but the elderly people are more susceptible to the high risk of death from illness. We know that all over the world the death tolls exceeds several hundred thousand people per year, but even in developed countries, this number is not accurately established, because health services usually do not check who actually died of influenza and who died from flu-like diseases " Even healthy people can get infected, and serious flu problems can develop at any age. People over 50 years old, very small children and people of any age with chronic diseases have a greater probability of influenza complications, such as pneumonia, bronchitis, sinusitis and ear infections. In some cases, autoimmune responses to infection of the influenza virus can contribute to the development of Guien-Barre syndrome. However, since many other infections can increase the risk of this disease, the flu can only be one of the important causes of epidemics. This syndrome is considered to also be a rare side effect of flu vaccine. In one of the reviews, the frequency is about one case per million vaccinations. Infect infection in itself increases both the risk of death (up to 1 per 10,000) and the risk of developing SGB to a much higher level than the highest level of alleged influence of the vaccine (OK. 10 times higher, according to the latest estimates).

Epidemiology

Seasonal oscillations

The flu reaches the peak of prevalence in the winter, and due to the fact that in the northern and southern hemispheres of winter comes at different times of the year, in reality there are two different flu seasons every year. That is why the World Health Organization (with the assistance of national influenza centers) recommends using two different vaccine drugs every year; One for the North, and the other for the southern hemisphere. For a long time, it is not clear why the flashes of the influenza occur seasonally, and not evenly throughout the year. One possible explanation is that in winter people are more likely located in the room, in close contact with each other, and it contributes to the transfer of a virus from a person to a person. Increasing the number of trips in connection with the winter holiday season on the Northern Hemisphere can also play a role. Another factor is that low temperatures lead to greater dryness of air, which can dry the mucus, preventing the effective displacement of viral particles by the body. The virus also survives longer on the surfaces at low temperatures. The air-drip transmission of the virus is the highest in low temperatures (below 5 ° C) with low relative humidity. Lower air humidity in the winter, it seems to be the main cause of seasonal influenza transmission in regions with temperate climates. However, seasonal changes in the infection level are also found in tropical regions. In some countries, these peaks of infection are observed mainly during the rainy season. Seasonal changes in the level of interaction depending on school quarters, which are one of the main factors of other childhood diseases, such as measles and cough, can also play a role in the development of influenza. The combination of these small seasonal effects can be enhanced by a dynamic resonance with endogenous cycles of the disease. H5N1 demonstrates seasonal variability of both people and birds. An alternative hypothesis to explain the seasonal fluctuations of the influenza infection is the impact of the level of vitamin D to the immunity to the virus. For the first time, this idea was proposed by Robert Edgar Hope-Simpson in 1965, he suggested that the causes of the flu epidemic in the winter period can be associated with seasonal vitamin D oscillations, which is produced in the skin under the influence of solar (or artificial) UV radiation. This can explain why the flu is observed mainly in the winter and during the rain rainy season, when people remain indoors, away from the sun, and their vitamin D levels fall.

Dissemination of the epidemic and pandemic

The antigen drift creates influenza viruses with slightly modified antigens, while the antigenic shift creates viruses with completely new antigens. Since the flu is caused by a number of species and strains of viruses, in any year some strains can extortion, while others create epidemics, and another strain can cause a pandemic. As a rule, in the normal two seasons of influenza per year (one by one for hemisphere), there are from three to five million cases of severe illness and about 500,000 deaths around the world, which, according to some definitions, is an annual flu epidemic. Despite the fact that the incidence of flu may vary widely in different years, approximately 36,000 deaths and more than 200,000 hospitalities are connected every year in the United States with influenza. One of the ways to calculate the mortality from influenza showed the average number of deaths per year at 41400 in the United States in the period from 1979 to 2001. Various methods of disease control and prevention centers (CDC) in 2010 reported a range from a low level of about 3,300 deaths to high - 49,000 per year. Approximately three times in a century there is a pandemic, which infects most of the population of the globe and can kill tens of millions of people. One study showed that if the strain with a similar influenza of 1918 with virulence would arise today, it could kill from 50 to 80 million people. New influenza viruses are constantly developing as a result of mutation, or recombination. Mutations can cause small changes in hemagglutinin and neuraminidase antigens on the virus surface. This is called an antigenic drift, which slowly creates an increasing variety of strains while one of them evolves, which can infect people who have immunity to previously existing strains. This new version then replaces the former strains, since it is quickly "rolled" on the population of the globe, which often leads to the epidemic. However, since strains produced as a result of the drift will still be quite similar to old strains, some people still have immunity to them. In contrast, when influenza viruses are recombined, they acquire completely new antigens, for example, by recombination between avian influenza strains and human flu strains; This is called antigenic shift. If a human flu virus is produced, which has completely new antigens, everyone will be exposed, and the new influenza virus will spread uncontrollably, which leads to a pandemic. In contrast to this model of pandemics based on antigen drift and shear, an alternative approach was proposed, in which periodic pandemics are manufactured by the interaction of a fixed set of viral strains with a human population with an ever-changing set of immunity to various viral strains. The time of generation of influenza (time from the beginning of one infection before the start of another) is very short (only 2 days). This explains why flu epidemiic starts and end in a short time, just a few months. From the point of view of public health, the flu epidemic quickly apply and they are very difficult to control them. Most of the influenza virus strains are not very contagious and each infected person will infect only 1-2 people (the main number of reproduction for influenza, as a rule, is about 1.4). Nevertheless, the influenza generation time is extremely short: the time of infection from person to person is only two days. The short time of generation means that the flu epidemic, in general, reaches a peak in approximately 2 months and quiet after 3 months: Therefore, the decision on intervention in the influenza epidemic should be taken earlier, and this solution is thus often done in the presence of incomplete data. Another problem is that people become contagious before they develop symptoms, which means that the premises of people in quarantine after they are ill, is not an effective method. At the middle person, the spread of the virus is usually at the peak in two days, while the peak of symptoms comes on the third day.

History

Etymology

The word "Influenza" comes from Italian and means "influence" and refers to the cause of the disease; Initially, the disease was attributed to unfavorable astrological influences. Changes in medical thoughts led to the name modification in "Influenza del Freddo", which means "the influence of the cold". The word influenza was first used in English to designate the disease, which we know today, in 1703 by J. Haugger from Edinburgh University in his dissertation "De Catarrho Epidemio, Vel Influenza, Prut in India Occidentali Sese Ostendit". Archaic terms for the symbol of influenza include epidemic Qatar, Grippe (from French, first used Molino in 1694), Pader and Spanish fever (especially for the pandemic strain of 1918 influenza).

Pandemia

The human symptoms in humans were clearly described by the hippocratic about 2400 years ago. Despite the fact that the virus seems to cause epidemics throughout human history, the historical influenza data is difficult to interpret, since symptoms may be similar to the symptoms of other respiratory diseases. The disease could spread from Europe to America at the beginning of the European colonization of America. Almost all the indigenous population of the Antille Islands was killed by an epidemic resembling flu, which broke out in 1493, after the arrival of Christopher Columbus. The first convincing record of the influenza pandemic dates back to 1580. The outbreak of the disease began in Russia and spread to Europe across Africa. In Rome, more than 8,000 people were killed, and several Spanish cities were practically destroyed. Pandemic sporadically continued during the 17th and 18th centuries, while the pandemic of 1830-1833 was particularly widespread; She infected about a quarter of all people who were influenced. The most famous and lethal flash was a 1918 influenza pandemic (Spanish flu) (type A flu, subtype H1N1), which lasted from 1918 to 1919. It is not known exactly how much this flu has killed a person, but, according to the estimates, the number of victims was from 50 to 100 million people. This pandemic was described as the "greatest medical holocaust in history" and, perhaps, she killed as many people as black death. This huge number of victims was associated with an extremely high level of infection, reaching 50%, and the extreme severity of symptoms may have been caused by hypercitisenemia. Symptoms in 1918 were so unusual that initially influenza was mistakenly diagnosed as a dengue, cholera or typhus. One observer wrote: "One of the most powerful complications was bleeding from mucous membranes, especially from the nose, stomach and intestines. Bleeding from ears and petechial hemorrhages in the skin also had a place. " Most deaths were associated with bacterial pneumonia, a secondary infection caused by influenza, but the virus also killed people directly, causing mass hemorrhages and swelling in the lungs. The 1918 flu pandemic (Spanish flu) was truly global, spreading even to the Arctic and remote Islands of the Pacific Ocean. An unusually severe disease caused death from 2 to 20% of the total number of infected, in contrast to the usual mortality from the influenza epidemic, which is 0.1%. Another unusual feature of this pandemic is that she mainly killed young people. 99% of pandemic deaths from influenza was observed in the age group to 65 years, and more than half of deaths - in young adults aged 20 to 40 years. This is unusual, since the flu is usually the most detrimental for the youngest (under the age of 2) and very old (over the age of 70) people. The total mortality from the pandemic of 1918-1919 is not known, but it is assumed that it was killed from 2.5% to 5% of the world's population. As many as 25 million, perhaps died during the first 25 weeks; In contrast, HIV / AIDS was lost 25 million in the first 25 years. Later influenza pandemic were not so destructive. They included the 1957 Asian influenza (type A, H2N2 strain) and 1968 Hong Kong flu (type A, strain H3N2), but even these small flashes claimed the lives of millions of people. During later pandemic, antibiotics were available to control secondary infections, and this may have contributed to a decrease in mortality compared with the Spanish flu in 1918. The first isolated influenza virus was a virus from poultry, when in 1901 the agent causing a disease called "Pernaya Plague" was passed through Shamberman filters, which have pores that are too small in order for their bacteria. The etiological cause of influenza, the family of Orthomyxoviridae viruses, was first discovered in the pigs Richard Shop in 1931. After this discovery soon followed the selection of the virus from the human body by a group of scientists under the leadership of Patrick Leidloou in the Medical Research Council of the United Kingdom in 1933. Waydl Stanley for the first time It was possible to crystallize the tobacco mosaic virus in 1935, and only after that the non-porous nature of viruses was evaluated. The first essential step towards the prevention of influenza was the development of an inactivated flu vaccine in 1944 by Thomas Francis Jr.. The scientist was based on the work of Australian Frank McFarlan Burtnet, who showed that the virus lost the virulence when he was cultivated in fertilized chicken eggs. The use of this observation by Francis allowed his group of researchers at the University of Michigan to develop the first flu vaccine, with the support of the US Army. The military took place participation in studies due to their experience gained during the flu epidemic during World War II, when thousands of soldiers were killed by a virus for several months. Compared to vaccines, the development of anti-influenza drugs leaks more slowly. Amantadine was licensed in 1966, and almost thirty years later, the development of the following grade preparations (neuraminidase inhibitors) began.

Society and culture

The flu is associated with direct expenses due to the loss of performance and related medical treatment, as well as indirect costs for preventive measures. In the United States, the flu is associated with expenditures of more than $ 10 billion per year, while it was estimated that the future pandemic could lead to costs of hundreds of billions of dollars in the form of direct and indirect costs. Nevertheless, the economic consequences of the past pandemic were not studied intensively, and some authors believe that the Spanish flu actually had a positive long-term effect on the growth of income per capita, despite a significant reduction in the working-age and severe short-term depressive effect. During other studies, attempts were made to predict the costs of such a serious pandemic as the Spanish influenza of 1918, to the US economy, when 30% of all workers were the patients, and 2.5% died. The incidence rate is 30% and a three-week duration of the disease will reduce the gross domestic product by 5%. Additional costs will come from medical treatment in the amount of 18 million to 45 million people, and the total economic damage will be approximately $ 700 billion. The profil costs are also high. Governments around the world have spent billions of US dollars to prepare and planning strategies in the event of a potential pandemic of the H5N1 bird flu, including the costs associated with the acquisition of drugs and vaccines, as well as the development of an educational alarm and strategy plan to improve cross-border control. On November 1, 2005, US President George W. Bush announced a national strategy to ensure the protection against dangerous pandemic flu asking for Congress to provide $ 7.1 billion to start implementing this plan. At the international level, on January 18, 2006, donor countries pledged to allocate $ 2 billion to combat bird flu during the two-day International Donor Bird and Human Influenza Conference held in China. When evaluating the H1N1 2009 pandemic in some countries in the southern hemisphere, the data suggests that all countries have experienced some time limited and / or geographically isolated social / economic effects and a temporary decline in tourism revenues, most likely because of the fear of the disease H1N1 2009. It is too early to talk about whether the H1N1 pandemic caused any long-term economic effects.

Research

Influenza studies include research on molecular virology, as a virus causes diseases (pathogenesis), immune response, viral genomics, and as a virus is distributed (epidemiology). These studies help in the development of measures to counteract the influenza; For example, provide a better understanding of the reaction of the body's immune system, which contributes to the development of vaccines, and the detailed idea of \u200b\u200bhow the flu is struck by the cells, contributing to the development of antiviral drugs. One of the most important fundamental research programs is a project for sequencing the flu genome, creates a flu sequence library; This library should help find out which factors make one strain more deadly than the other, which genes are most influenced by immunogenicity, and as a virus evolves over time. Research in the field of new vaccines is of particular importance, since at present the production of vaccines is a very slow and expensive process, in addition, vaccines must be reformulated annually. Sequencing the flu genome and recombinant DNA technology can accelerate the generation of new vaccine strains, allowing scientists to replace new antigens in a previously developed vaccine strain. New technologies for growing viruses in cell culture, which promise higher developing, less price, quality improvement and best potential are also being developed. The study of the Vaccine of Universal Influenza A, directed against the external domain of the transmembrane virus protein M2 (M2E), is held at the University of Ghent Walter Firsce, Xaviere Saless and their team and now successfully completed the phase I clinical trials. Some success was observed in the study of the "universal flu vaccine", which produces antibodies against proteins on a viral shell, which mutated less quickly, and, thus, one injection can potentially provide a longer protection effect. A number of biological preparations, therapeutic vaccines and immunobiological drugs are also investigated for the treatment of infection caused by viruses. Therapeutic biological preparations are designed to activate the immune response to the virus or antigens. As a rule, biological preparations are not targeted on metabolic pathways as antiviral drugs, but stimulate immune cells, such as lymphocytes, macrophages and / or antigen-representing cells, in an attempt to initiate an immune response against cytotoxic actions against the virus. Flu models, such as mouse flu, are convenient models to verify the effects of preventive and therapeutic biological preparations. For example, a T-cell lymphocyte immunomodulator inhibits viral growth in a mouse flu model.

Other animals

The flu is striking many types of animals, as well as the transfer of viral strains between the species. Birds, presumably, are the main reservoirs of influenza viruses among animals. Sixteen forms of hemagglutinine and nine forms of neuraminidase were revealed. All well-known subtypes (HXNY) are found in birds, but many subspecies are endemic in people, dogs, horses and pigs; Populations of camels, ferrets, cats, seals, minks and whales also show evidence of preliminary infection or influenza. The flu virus options are sometimes referred to as the species for which the strain is endemic or to which it is adapted: bird flu, human flu, swine flu, horsepower influenza and dog influenza. (Feline flu usually belongs to rinotrachet cats or calicivirosis, and not to infection with influenza virus.) In pigs, horses and dogs, the symptoms of influenza are similar to the symptoms of the human flu and include cough, fever and loss of appetite. The frequency of animal disease is not so well studied as a person infections, but the flareness of the flu in seals caused about 500 deaths of seal off the coast of New England in 1979-1980. Nevertheless, the flashes in pigs are commonplace and do not cause great mortality. Vaccines were also developed to protect poultry from bird flu. These vaccines can be effective for multiple strains and are used either as part of a preventive strategy, or in combination with animal selection in attempts to eradicate outbreaks.

Bird flu

The symptoms of influenza in birds are variables and may be nonspecific. Symptoms in the infection of bird flu infection with a low pathogeneity can be soft and include withdrawn feathers, a slight reduction in egg production or weight loss in combination with minor respiratory diseases. Since these light symptoms may make it difficult to diagnose in field conditions, tracking the spread of avian flu requires a laboratory test of samples from infected birds. Some strains, such as Asian H9N2, are highly visible for poultry and can cause stronger symptoms and significant mortality. In the most pathogenic form, the flu in chickens and indeek causes a sudden appearance of heavy symptoms and almost 100% mortality within two days. Since the virus is rapidly distributed in close conditions of agriculture in chickens and turkeys, these outbreaks can be associated with large economic losses for poultry farms. Adapted to birds, highly pathogenic strain H5N1 (the so-called HPAI A (H5N1), "HighlyTogenic strain of a Bird influenza and subtype of the H5N1 virus") causes H5N1 influenza, widely known as "bird flu" or simply "bird flu" and is endemic in Many populations of birds, especially in Southeast Asia. This Asian strain HPAI A (H5N1) is distributed throughout the world. It is an epizootic (epidemic is not in a person) and a panzootic (disease affecting animals of many species, especially on a large area), and can kill tens of millions of birds and stimulate the rejection of hundreds of millions of other birds in an attempt to control its distribution. Most of the "avian influenza" in the media, and most of the references to H5N1 - about this particular strain. Currently, HPAI A (H5N1) is a bird disease, and there is no evidence of the effective transfer of HPAI A (H5N1) from a person to man. Almost in all cases, infected people have extensive physical contact with infected birds. In the future, H5N1 can mutate or recombine into a strain, contributing to the effective transmission of the virus from a person to a person. The exact changes that are necessary for this are not fully understood. However, due to the high mortality and virulence of H5N1, its endemic presence and greater and ever-increasing reservoir of biological owners, the H5N1 virus represented the World Pandemic Threat During Flu 2006-07, and billions of dollars were spent on the H5N1 virus studies and preparations for the possible Pandemic influenza. In March 2013, the Chinese government reported three cases of H7N9 influenza infection in humans. Two of them died, and the third was seriously sick. Although it was not believed that the strain of the virus could effectively spread between people, by mid-April, at least 82 people fell ill from H7N9, 17 of which died. These cases include three small family clusters in Shanghai and one cluster between a neighboring girl and a boy in Beijing, which indicates the possibility of transmitting a virus from a person to man. WHO notes that in one cluster there were no two cases of diseases confirmed in the laboratory, and further indicates that some viruses are able to cause limited transmission from person to person in conditions of close contact, but are not transmitted in sufficient volume to cause large outbreaks.

Swine flu

In pigs, swine flu causes rise to temperature, lethargy, sneezing, cough, breathing difficulty and decline in appetite. In some cases, infection can cause miscarriage. Although mortality is usually small, the virus can lead to weight loss and poor growth, as a result of which lead to economic damage to farmers. Infected pigs can lose up to 12 pounds of body weight for from 3 to 4 weeks. The direct transmission of the influenza virus from pigs to a person is sometimes possible (this is called zoonous swine flu). In general, it is known about 50 cases of human disease that took place from the moment the virus was found in the middle of the 20th century, which led to six deaths. In 2009, the strain of the H1N1 of pork origin virus, which is usually referred to as "swine flu", is the cause of the 2009 influenza pandemic, but there is no evidence that it is an endemic disease in pigs (i.e., actually swine flu ) Or transmitted from pigs to people, instead of spreading from a person to a person. This strain is the recombination of several H1N1 strains, which are usually located separately, in humans, birds and pigs.

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The flu is a severe infectious disease that can affect people of any age and gender. According to statistics, millions of people around the world die from the influenza and its complications. Thus, the flu is a serious danger to life and health. Therefore, it is very important to know how the basic influenza symptoms look like.

Description of the disease

The flu was known for a long time, from ancient times. However, he became a serious problem only in the twentieth century, as the most terrible bacterial infections retreated - plague, cholera, typhus. A well-known Pandemic of the Spanish Influenza, which took place at the beginning of the twentieth century and struck almost all countries and continents. Then two tens of millions of people died from the disease, and many of them were young and healthy. Often today in separate regions there are outbreaks of new dangerous varieties of disease, such as pork or avian influenza.

However, the epidemics of ordinary flu, sometimes referred to as seasonal, can be dangerous. In seasonal influenza, the disease is striking many children, older people and people with chronic diseases and other health problems. The flu is also dangerous for pregnant women, as it can harm the child's health.

It is also worth considering that the disease causes great damage to the economy of any country that is exposed to the epidemic, since a significant part of the working population is disabled for a period of time. In general, in seasonal flu during the year, up to 15% of the world's population may be ill. And about 0.3% of diseases ends with a fatal outcome.

As flu arises

The disease is caused by the smallest biological particles - viruses. The influenza virus was highlighted in the middle of the 20th century. It refers to a group of RNA-containing viruses, that is, viruses that store genetic information in the RNA molecule. Three kind of virus is known - A, B and C, inside of which virologists allocate individual strains and serotypes, depending on which proteins contain the flu virus.

The characteristic feature of the influenza virus is its ability to constant mutation. And this means that every year all new strains appear, and if a person has surpassed the flu and acquired a resistance to infection with one strain, this does not mean that he will not be able to pick up the disease caused by another strain of the virus.

The most severe flu epidemic causes viruses of the genus A. They can be transmitted from both a person to person and from animals to man. The viruses in less often become the cause of epidemics, although among viruses of this group there are also those that cause severe forms of the disease. The influenza virus is never causes epidemics. This is a relatively safe for a person's type of virus. It is striking only the most weakened categories of people.

The influenza virus is usually quite resistant to adverse external influences. It can persist in frozen form up to several years. At room temperature on various items, it can be saved for several hours. Drying and heating to +70 ºС kills the virus for a few minutes, and boiling does it almost instantly. The virus is also sensitive to ultraviolet, ozone and some chemicals.

In most cases, the virus is transmitted by air-droplet, with sneezing or cough, in some cases, even with a conventional conversation. It may also be infected through household items, for example, when a person concerns the surfaces of the surfaces of the objects where the virus is located, and then faces. When hitting the mucous membranes of the respiratory tract, the virus begins its reproduction.

The incubation period of influenza groves from various factors - the number of virus particles in the body, the state of the human immune system, such as a virus, etc., and can vary from several hours to 5 days.

A person infected with the virus may be dangerous to others, as it spreads around itself the causative agents of the disease. This danger is maintained even if the person has not been sick or have already silenced the flu. However, the most dangerous for the influenza man in the first two days of the disease.

Forms of the disease

There are several basic forms of the disease, depending on the intensity of the observed symptoms:

• easy
• average
• heavy
• toxic
• lightning.

With light and medium flu forms, treatment can be carried out at home. In other cases, hospitalization is recommended. This is especially true of those who have chronic diseases of the cardiovascular system and the lungs.

Complications of influenza

Most of the fatal cases in the disease of the flu are associated not with the disease itself, but with characteristic complications for it. Flu complications affect, above all, cardiovascular and nervous systems, lungs, kidneys and liver. The most dangerous complications of influenza are:

• viral pneumonia, severe treatment even in hospital conditions;
• inflammation of the heart muscle - myocarditis and fabrics surrounding the heart - pericarditis;
• inflammation of brain shells () and brain (encephalitis);
• severe renal and liver failure;
• early abortion of pregnancy and fetal infection in pregnant women.

Symptoms

Influenza symptoms are extremely diverse. The main symptoms include:

• high temperature
• cough,
• headaches,
• pain in body and muscles,
• sore throat,
• pain in the eyes
• rubber (rhinitis),
• weakness and Breakiness
• disorders of the gastrointestinal tract.

All these symptoms, with the exception of high temperatures, can not always manifest itself and not all patients.

Heat

For this, the symptom is characterized by high values. The typical temperature at the beginning of the disease is usually higher than +39 ºС, and often it can turn out for the mark of +40 ºС. Only with the light shapes of the flu, the temperature can fluctuate at the mark of +38 ºС. Such a strong temperature increase is a consequence of intoxication of the body, as well as the reaction to its immune system.

Another feature of increasing temperature is that it usually occurs very sharply, literally in a few hours. The duration of the period during which the temperature in the patient is increased depends on the severity of the disease and whether the antipyretic means takes. It usually lasts 2-4 days. Then the temperature drops to subfebris values. In the case of heavy influenza forms, the high temperature is poorly shot down with the help of antipyretic agents. Or knocks on a very short period of time.

Cough

Influenza viruses are mostly affected by the mucous membrane of the bronchi. Therefore, with a cough influenza, a typical symptom appears in 9 out of 10 patients. However, the cough is not always manifested in the first hours of the disease. In addition, often cough can be relatively weak compared to the cough observed in other respiratory diseases. Cough is usually a continuous character, it can handle a person and not give him to fall asleep.

At the beginning of the disease, cough is usually dry and unproductive. As the wet wet, the cough is replaced by wet.

Head and Body Pain

Headaches, pain in the chest, as well as unclear pains in other parts of the body, especially in the muscles of the legs, are a consequence of the body intoxication. Often these are the first symptoms of influenza, appearing even before increasing the temperature. The painful sensations in the muscles can wear the character of fraud. Headache is usually concentrated in the frontal zone, although it can spread throughout the head. Sometimes it can be observed in the eyes, lights. All this is quite commonly encountered influenza symptoms.

Larygit, pharyngitis, runny nose, sinusitis

Symptoms of inflammation of the mucous membranes of the upper respiratory tract - runny nose, sore throat, sneezing can often not be observed at all. However, such symptoms are also found (about half of the cases). Often they are explained not to the influence of influenza viruses themselves, but by secondary bacterial infection. Most often, children suffer from such phenomena.

Other symptoms

Sometimes there are disorders of the gastrointestinal tract - nausea, dyspepsia, loss of appetite. Sometimes vomiting and diarrhea are possible. Although in general for influenza, such symptoms are uncharacteristic.

Also, against the background of the high temperature, the patient may have increased sweating, redness and hyperemia of the skin, rapid heartbeat, reduced blood pressure, heart rate disorders. When listening to the heart, muted tones are noticeable, systolic noise.

Duration of the disease

The active phase of influenza with clearly pronounced symptoms usually lasts no more than 3-5 days. A longer case of the disease increases the risk of various complications - inflammation of lungs and pleura, otitis, myocarditis, endocarditis, encephalitis, liver and kidney lesions.

What are the differences in flu species

With a light form of influenza, the patient has a relatively low temperature - in the +38 ºС area, and sometimes subfebrile, the cough is poorly expressed or may be absent. General well-being satisfactory. The active phase of the disease lasts 2-4 days, and complete recovery occurs a week later.

In case of moderate severity, a temperature is observed about +39 ºС. Cough is moderate. The health of the patient is satisfactory, despite the strong weakness. Headaches may be present. With severe flu, the temperature rises to +40 ºС. Strong headaches and lubricants in the whole body. Strong cough, nasal bleeding is possible. With an increase in the temperature above +40 ºС, cramps, nonsense, hallucinations, loss of consciousness are possible.

The lightning form is a rare form of influenza, but this is not less dangerous. It is characterized by a very rapid development of symptoms, an increase in temperature to +40 ºС, for several hours, the presence of signs of general intoxication of the body. The disease can end the pulmonary and brain edema and fatal.

What to do at the first symptoms?

In the event that a person has the first signs of influenza, the first thing that needs to be done is to call a doctor at home. The main reason for calling a doctor is a high temperature - over +38 ºС. To go independently in a clinic with such a temperature is dangerous not only for the patient himself, but also for the surrounding people who can infect the patient. Especially vulnerable to infections Children and the elderly people, people suffering from cardiovascular diseases and kidney diseases. However, even adult and healthy people can die from toxic flu. This development of events is not completely excluded.

Before the arrival of the doctor, it is necessary to observe the bed mode. The antipyretic and anti-inflammatory means are better not to take if the patient's condition is satisfactory, since their reception can distort the clinical picture. The doctor should examine the patient and decide whether he should be treated at home, or in a hospital. If the treatment is held at home, the doctor will appoint all the necessary medicines.

For the treatment of influenza can be used:

• etiotropic agents
• immunomodulators
• symptomatic agents (anti-inflammatory and antipyretic drugs).

Expectorant and muscolithic preparations are accepted for the treatment of cough. For the treatment of throat and runny nose, rinsing, inhalation, nasal drugs are useful.

Of great importance for speedy recovery, the correct diet, the use of vitamins, abundant drink, compliance with the beddown is also.

What is the difference between flu and ORVI

Influenza is a less common disease than a banal cold. But at the same time more dangerous. In everyday life, the flu is often customary to call any OZ, accompanied by an increase in temperature. But it is completely wrong. Attack the body, including the respiratory tract, can various bacteria and viruses, but the flu is only a disease caused by the influenza virus, and no other.

To the number of viruses causing so-called acute respiratory viral diseases (ORVI) include:

• rinoviruses
• adenoviruses
• enteroviruses
• paragrippa viruses.

The probability of catching the disease caused by any such virus is much higher than to get infected with the flu. Moreover, a separately taken person may be hurting the flu far away every year, while it can carry respiratory diseases every year caused by other viruses.

Such a situation generates a somewhat indulgent attitude towards the disease. Say, I have been sick with the flu in winter - it heatured, poured, pulled the papers for a couple of days, and that is terrible, not died! So why do you need vaccinations and other measures to prevent influenza? Meanwhile, this person could not even face a flu virus as such.

Most people who collided precisely with the flu, and not with ORVI, can distinguish the symptoms of influenza from the SMI symptoms. However, in some cases it can be difficult. Viruses such as paragripping virus, which is reflected in its name, can give symptoms, very similar to the symptomatics of influenza light and medium severity. Therefore, it will not be superfluous to remind what kind of symptoms are more peculiar to the influenza than ORVI.

First, it is a sharp rise in temperature to high values, in + 39-40 ºС, for a short period of time, literally in a few hours. For most other respiratory diseases, the temperature rise occurs much slower, that is, half a day or one day in humans the temperature is subfebrile, and before values \u200b\u200bin + 38ºС or even + 39ºС it rises only the next day. This feature of the disease is very dangerous, since the fever can often find a person by surprise, for example, when he is at work.

Secondly, it is the temperature level itself. With most ORVI, the temperature still does not overcome the mark of +39 ºС. With the flu +39 ºС is not the limit. Often the temperature can jump up to the level of +40 ºС. However, in some other infectious diseases, such a high temperature is also possible, for example, with enterovirus infection. However, it is more common in summer.

Thirdly, this is the time of respiratory, symptoms, such as cough. With influenza, the symptoms of this type usually appear only after the temperature increases. With ORVI, the person can have a sore throat all day, and only after this temperature will occur.

Fourth, this is the severity and the number of respiratory symptoms themselves. With the present influenza patient, only cough is usually tormented, which, however, can be very strong and breast congestion. Faringitis, laryngitis and rhinitis appear rarely. Usually they are associated with a bacterial infection who has joined later.

Fifth, these are general signs of intoxication - headache and lubrication in the whole body, first of all, in the muscles of the legs. For ARVI, such symptoms are usually not characteristic, in contrast to influenza. Also, what is important, such symptoms for influenza may appear even before increasing the temperature and appearance of respiratory symptoms, and, thus, be the first signs of an impending disease. Symptoms such as strong malaise, fatigue and weakness are also not characteristic.

Sixth, this is the duration of the disease and the recovery period. When ORVI, the temperature usually holds 2-3 days, and after the temperature drop in temperature, the person usually feels good. With flu, the temperature lasts 4-5 days, but even after the fever passed, a person can feel the bombardness and ailments during a couple of weeks.

The flu is one of the most common infectious diseases, refers to a group of sharp respiratory viral infections.

The influenza viruses cause this disease, which at the moment there are more than 2,000 species. These viruses can spread in the form of epidemics whose lifting is usually on the autumn-winter period, and pandemics that are registered every 30-40 years. Many patients belong to the influenza rather dismissively, considering it a common "cold", while annually from this disease, about 250-500 thousand people die in the world.

People of all age categories are susceptible to the flu virus, but this disease is the greatest danger for persons of old age, children, pregnant women, as well as people suffering from diseases of the lungs and hearts. The source of the influenza is already a sick person who emits the virus through cough, sneezing, etc. Having an aerosol transmission mechanism (inhalation of mucus drops, saliva), the flu spreads quite quickly - the patient is a danger to others during the week, starting From the first hours of infection.

Symptoms of influenza

Influenza, whose symptoms are not specific, distinguish from other ARVIs without special laboratory research is almost impossible.

The diagnosis of "influenza" in practice is established mainly only on the basis of an epidemic situation.

The disease begins, as a rule, is sharp: the body temperature rises to 38-40 0 s, znobit, headache, brutal pain in the joints and muscles, weakness. The discharge from the nose cannot be called a typical symptom for influenza, because for this disease, on the contrary, dryness is characterized in the nose and sip. In most cases, an intense dry cough occurs, which is accompanied by pain in the sternum. Inspection of the patient can reveal more signs of influenza as hyperemia of the face, arterial hypotension, the injection of Schler ("Red Eyes"), graininess and hyperemia of solid and soft sky, relative bradycardia.

Symptoms of influenza are usually saved for 3-5 days, after which the patient is amended.

With severe disease, the most frequent complications are otitis, sinusites, pneumonia, but it is possible to develop such consequences as brain edema, vascular collapse, hemorrhagic syndrome, the addition of secondary bacterial complications, aggravation of chronic diseases.

Physic treatment

For a long time, the treatment of influenza was only symptomatic and assumed to receive antipyretic, expectorant, antitussive drugs, vitamins, in particular larger doses of ascorbic acid, as well as compliance with the beddown and consumption of sufficient liquid. Today, symptomatic treatment of flu has not lost its relevance, however, at the same time, it was understood that, in addition to eliminating the symptoms of the disease, it is necessary to fight directly and with its cause, that is, with a virus.

Medications for influenza must be appointed by the doctor, today it is effective in antiviral drugs, provided that their reception will be started before the clinical manifestations of the disease.

To suppress the propagation of the virus in the body, decline in the severity of symptoms, reduce the duration of the disease and reduce the frequency of secondary complications, it is recommended to take such antiviral drugs as Zanamivir and Ozheltonivir (Tamiflu). These drugs from influenza are effective in relation to many flu strains, but their reception is possible only for its intended purpose and under the control of the doctor. To block proton pumps and prevent the penetration of virus into cells, preparations of Rimantadine and Amantadine are used. The antiviral and immunostimulating properties have interferon preparations (infrapperion, inharon, amicin) and interferon inductors (Kagole, cycloferon), but independent treatment of influenza by drugs is undesirable, the decision to accept the feasibility of their reception.

The right to existence also have homeopathic medicines for influenza, among which are widely popular with otsilocqing, which is an extract of heart and musk duck liver. Despite the fact that manufacturers of certain drugs based on animal organisms or plant extracts argue that their means are effective in the treatment and prevention of influenza, as a rule, these statements do not have clinical confirmations.

Prevention of influenza

Influenza vaccination is a traditional way to prevent the disease. Vaccination is most shown to children, elderly children, patients with chronic diseases of the lungs and hearts, doctors. Influenza vaccination involves the introduction of a healthy person a lively, inactivated vaccine containing antigens usually three virus strains selected based on WHO recommendations.

Emergency prevention of influenza can be called intranasal (drops in the nose) administration of interferon (Naoferon), which is advisable to apply after close communication with infected. Also, with direct contact with patients from infection with influenza, the use of gauze bandage can protect, the use of remantadadine or lubrication by oxoline oxoline moss.

Non-specific influenza prevention suggests: airing the room, frequent hand washing with special means, wet cleaning with the use of disinfectants, as well as air disinfection with ultraviolet irradiation, catalytic cleaners, aerosol disinfectors. To maintain immunity capable of resisting the virus, it is necessary to include in the diet products rich in vitamins, lactic acid bacteria, as well as use honey, propolis, royal milk.

The prevention of the flu epidemic largely depends on the consciousness of the already ill person who needs to avoid public places with a large cluster of people for whom the patient, especially coughing and sneezing, represents the potential danger of infection.

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Special attention should be paid to sick children, elderly people and those who have other diseases.

Causes of influenza development

Influenza viruses constantly exist around us. It is typically very quickly changed (to mutate), and that is why the flu can be sick many times. The virus applies very quickly. Sneezing, coughing, talking, sick people splashing the smallest droplets in the air, in which there are viruses. Doctors say that the flu is transmitted to air-droplet.

Symptoms of influenza

In a sharp period of the disease, you can have a high temperature, headache, and joints (lubrication), followed by a runny nose, cough and throat pain. Such a state can last a week.

In some cases, the disease applies to the lungs, causing and pneumonia. It is more often found in elderly, smokers, people with poor health or patients who have asthma or other lung diseases.

What can you do

It is better to relax until you feel better, and the temperature will not drop.

A day well drink up to 8 glasses of liquid (water, juices, sweet herbal tea with lemon and honey / if you do not have). It is especially important to drink a lot if you have a high temperature, and you sweat a lot. Do not drink strong tea, coffee or alcoholic beverages, because They do not fill the lack of fluid in the body, and on the contrary, increase it. Fresh lemon juice, mixed with honey and hot water, warm milk with honey reduce and soften the dry cough. There is a better easy food, and only when you want.

You can take medications that facilitate pain and reduce the temperature. Children should not give aspirin (), for them it is better to buy children's paracetamol in the pharmacy. Before taking a medicine and especially to give it to children, carefully read the instructions on the package and follow all the recommendations.

You can consult with a doctor or with a pharmacy officer about new drugs that improve the health with flu and reduce the period of time when you feel very bad. But keep in mind that usually this kind of drugs must be taken within the first 48 hours from the moment of the appearance of the first symptoms of the disease (lubrication in the joints and an increase in body temperature).

What can a doctor

It is best to immediately consult a doctor (call a doctor at home) and take a hospital leaf. If you go to work, to the store or in any other public place, then you are not only risking to get some complication, but also contribute to the spread of the disease. Be sure to contact the doctor elderly or often and for long-friendly people, if a child fell ill or if an adult enhanced temperature holds longer than 4 days.

The flu is caused by viruses, so the use of antibacterial drugs will not help. Antibiotics appoints a doctor only in the case of the development of complications caused by bacteria.

Preventive measures

If you have a high risk of developing complications or a high likelihood of influenza disease (including a profession associated with: Militiamen, medical workers, teachers, employees of children's institutions), then the doctor may offer to make vaccination. Flu vaccination is better held in October-November. You can refer to the doctor or in vaccine centers. Vaccination does not give 100% guarantees that you will not get sick, but significantly reduces the risk of the disease.

Change annually, depending on species of viruses, which will allegedly lead to the development of the epidemic. Vaccination does not conduct children under 6 months, people with allergies on chicken protein or those who had previously had a reaction to the introduction of flu vaccine.