How to treat group B influenza. Influenza B: symptoms and treatment in children

Contents of the article

Flu(synonyms for the disease: influenza) is an acute infectious, highly contagious disease, caused by influenza viruses, transmitted by airborne droplets, characterized by an acute onset, a short febrile period, significant intoxication, symptoms of damage to the mucous membranes of the upper respiratory tract and frequent complications, mainly from the respiratory system.

Historical Flu Data

It is believed that influenza was first described and isolated as a separate disease by the Frenchman Etienne Pasquier (1403) based on an analysis of the epidemic that swept through Europe. Since that time, about 20 pandemics have been known. The largest of them is the pandemic of 1918-1919 pp. (“Spanish Flu”), during which about 500 million were ill and 20 million people died, and 1957-1959 pp. (Asian flu), when more than 2 billion people were ill and at least 1 million died. Until recently, in addition to the name influenza (from the French Gripper - to grab), the synonym for influenza was used. The virus was discovered by R. Shope (1931) and W. Smith, S. Andrews, P. Laidlaw (1933).

Etiology of influenza

Influenza viruses (A. B, C) belong to the Orthomyxoviridae family, containing single-stranded RNA. The fragmentation of the genome leads to a high frequency and efficiency of recombinations, i.e. significant changes in the antigenic and biological properties of the pathogen. Virions are sized (80-120 nm), mostly spherical in shape. Influenza A virus has two main types of antigens - hemagglutinin (H, 11 subtypes) and neuraminidase (N, 8 subtypes). The virus is well cultured in chicken embryos. Among experimental animals, primates, hamsters, and mice are sensitive to it. In addition, a large variety of cell cultures are used for cultivation. Capable of agglutinating human erythrocytes (especially O (I) group), chicken and other vertebrates.
Low resistance to environmental factors. Drying, sudden changes in temperature and humidity have a detrimental effect on its virulence. Highly sensitive to disinfectants, UV radiation, ether. Influenza viruses B and C do not differ in significant antigenic variability and are less important in the occurrence of epidemics.

Epidemiology of influenza

The main source of infection is a sick person. Serological and virological studies, observations of epizootics on livestock farms, poultry farms, etc. does not deny the possible role of animals as a reservoir of infection.
The mechanism of transmission of infection is airborne.
A sick person, already in the last hours of the incubation period and in the first 2-3 days of illness, releases a huge amount of virus in an aerosol when breathing, coughing, sneezing. On the 4-7th day from the onset of influenza, patients (convalescents) are no longer infectious. The increase in incidence in areas of temperate and cold climates occurs in winter. This is due to some extent to the predominant stay in enclosed spaces, lower relative air humidity, which contributes to the preservation of the infection in aerosols, and the like. Epidemics of influenza A develop rapidly, 30% of the population gets sick within 1-2 months, influenza B develops more slowly, no more than 30% of the population gets sick in 2-4 months, type C virus causes only sporadic cases of the disease. The importance of hypothermia and other stress factors in the occurrence of the disease has not been proven.
Flu- one of the most difficult problems in medicine. Its impact on human health cannot be taken into account, and the socio-economic damage from epidemics is enormous. The emergence of epidemics and pandemics is associated with urbanization. Numerous contacts during work, social activities and recreation, the possibility of rapid movement of large masses of people by transport, especially urban transport, lead to the rapid spread of the disease. This is facilitated by the large number of mild (erased) forms of influenza, which are usually carried on the legs. The second reason for the potential pandemic nature of influenza is the possibility of complete (shift) and partial (drift) changes in the antigenic structure of the virus. The emergence of new subtypes of the virus leads to pandemics. In people who have had the flu, antibodies to the type A virus persist for 1-3 years, and to the type B virus for 3-6 years.

Pathogenesis and pathomorphology of influenza

In the form of an aerosol, the virus enters the mucous membrane of the upper respiratory tract. Already after C-5 hours, massive reproduction and release of virions from destroyed cells is observed. The process is growing exponentially. Due to the cytopathogenic effect of the virus, destruction and desquamation of epithelial cells occurs with the advent of interstitial tissue and capillaries, which facilitates the penetration of the pathogen into the blood. Next, the viremia phase begins, which covers the direct influence of virions, the action of preformed derivatives of destroyed cells, accompanied by significant toxicosis and a complex immuno-allergic reaction. As a consequence of rapidly growing toxicosis and capillary toxicity, functional disturbances in the activity of the nervous system and circulatory organs are observed. There is much evidence of the direct damaging effect of virions that are part of immune complexes, as well as defective virions on the tissue of the brain, heart, blood vessels, kidneys, and lungs. In this phase, specific and nonspecific protective factors operate. On the 2-3rd day from the onset of the disease, a phase of predominant damage to the respiratory tract begins, which is accompanied by a secretory reaction and intense desquamation of the epithelium. Recently, data have appeared on the possibility of long-term persistence of the influenza virus in the form of immune complexes and defective virions, which opens up new, even unknown aspects of the influenza problem.
The mucous membrane of the upper respiratory tract and bronchi is hyperemic (fiery red), edematous, with hemorrhages, and sometimes covered with fibrinous films. Histological changes - desquamation of the epithelium, circulatory disorders, capillary congestion, perivascular edema, dystrophic changes in the cerebral cortex, subcortical nuclei, piriform neurons (Purkin cells). Dystrophic changes in other organs do not have signs characteristic of influenza.

Flu clinic

The incubation period lasts from several hours to 2-3 days. The initial signs of the flu are general discomfort, mild chills, nasal congestion, dryness and dandruff in the throat.
Within a few hours, fever appears (38-40 ° C), which is accompanied by intense headache, especially in the frontal, temporal and superciliary areas. Characterized by pain in the eyes, which intensifies with their movements and in bright light. General weakness, pain in muscles and joints increases, sometimes due to pain in the eyes and head it does not attract the patient’s attention. During this period of illness (1.5-2 days), significant disturbances in the general condition are possible - dizziness, short-term loss of consciousness, nausea, vomiting, decreased blood pressure. Preschool children sometimes experience convulsions with loss of consciousness at the height of fever.
A characteristic sign is hyperemia and swelling of the face, injection of scleral vessels. The skin of the extremities and torso is, as a rule, slightly hyperemic; in severe forms, pallor and sometimes general cyanosis are observed. The mucous membrane of the soft palate and the posterior wall of the pharynx is characterized by bright hyperemia and pinpoint hemorrhages, dilation of the vessels of the posterior wall of the pharynx, and hypertrophy of the follicles. Note the dryness and granularity of the mucous membrane, the flu-like tongue - with unchanged shape and size, the moist mucosa is covered with a bluish-white coating with porcelain opalescence (Fezan's symptom).
The frequency, intensity of the pulse, and blood pressure fairly objectively reflect the severity of the condition. If the toxicosis is significant, tachycardia, pulse tension, decreased blood pressure are observed, and in especially severe cases - relative or absolute bradycardia.
Damage to the respiratory organs in the first two days does not have diagnostic clarity. Auscultation - vesicular or harsh breathing, especially in the posterior-lower sections. X-ray - increased vascular pattern, expansion of the roots of the lungs as a result of congestion and edema.
A special place in influenza belongs to damage to the nervous system. Recent research results prove that all severe forms of influenza should be considered encephalitic syndrome. This is evidenced by both the given signs (stupefaction, loss of consciousness, severe headache) and possible manifestations of intracranial hypertension (dizziness, hyperesthesia, nausea, vomiting, hyperreflexia, convulsions). In addition, encephalography, echolocation, and cerebrospinal fluid studies confirm changes in the central nervous system that go beyond neurotoxicosis.
On the third day of uncomplicated influenza, regardless of the severity of the course, the body temperature drops to low-grade fever, the condition improves significantly, and general weakness decreases. Toxicosis is replaced by a dry cough and catarrhal manifestations that appear or intensify. The cough is almost constant, sometimes unbearable. If we take into account the impossibility of nasal breathing and serous nasal discharge, then, despite objective improvement, most patients feel unwell. This condition lasts 3-5 days, after which recovery occurs, but within another 1-2 weeks, cramping, adynamia, and decreased performance are observed. Blood tests reveal leukopenia with relative lymphocytosis.
Clinical picture of influenza there is significant variability. This applies to both severity and the possibility of developing various complications. Erased and mild forms of influenza are diagnosed taking into account epidemiological history.
The most severe and prognostically dangerous form of influenza is with the development of meningoencephalitis, which is difficult, but possible, to recognize in the first days by inadequately significant neurological symptoms. This is primarily a syndrome of cerebral hypertension, but with inconsistency of meningeal symptoms. Symptoms of severe encephalopathy (drowsiness, agitation, delirium, convulsions) come to the fore. Influenza encephalitis can develop on the 4-5th day of illness and after mild forms of it. Hemorrhagic syndrome (point hemorrhages in the skin and mucous membranes, hemorrhagic cerebrospinal fluid) in its action form indicates a particularly severe course and prognosis. The possibility of arachnoiditis as an isolated lesion during influenza is not denied, but more often it is diagnosed as a consequence of a severe form of influenza, or rather, an unidentified influenza meningoencephalitis.
Lesions of the peripheral nervous system may include neuritis of the trigeminal, facial and other nerves, and less commonly, polyneuritis and polyradiculoneuritis. As a rule, these syndromes acquire clinical manifestations during the period of convalescence.

Complications of influenza

The most common complication of influenza is pneumonia.
According to experimental studies, its etiology can be primary viral, post-influenza bacterial and mixed viral-bacterial. The frequency of pneumonia in different epidemics varies significantly (5-25%). The population at greatest risk is young children and the elderly. It should be remembered that primary viral pneumonia almost never ends and, due to the activation of endogenous flora, acquires the characteristics of a bacterial one.
A feature of influenza (post-influenza) pneumonia is a significant polymorphism of symptoms. As a rule, against the background of toxicosis and catarrhal manifestations, on the 4-5th day of illness the body temperature does not normalize, the barking cough changes to dry or wet, and little bothers the patient. There is no shortness of breath, or it is observed only in case of physical activity. There may be a slight tingling sensation under the shoulder blades during a deep breath. Auscultation: dry and wet dry and puffy rales, slight shortening of percussion sound over various parts of the lungs, which is especially clearly revealed during percussion of symmetrical areas. Radiologically, small-focal bronchopneumonia is most often found, although other forms are possible (interstitial, lobar, etc.).
Pneumonia with influenza tends to be protracted and sluggish.
One of the severe complications (course options) is stenosing laryngotracheitis in infants and preschool children. The syndrome can develop already in the first day. Against the background of the child's anxiety, stenotic breathing, inspiratory shortness of breath, barking cough, and increasing hypoxia occur. Laryngeal stenosis due to tissue edema and spasm is associated with the anatomical and physiological characteristics of the body of young children and, to some extent, is phenotypically determined: stenosis most often occurs in children with significant paratrophy, prone to allergic reactions.
In addition to the already mentioned complications from the nervous system, pneumonia, laryngotracheitis, due to the activation of bacterial flora, influenza can be complicated pharyngitis, tracheobronchitis, sinusitis, frontal sinusitis, otitis and eustachitis, With. damage to the mucous membranes in which virus reproduction occurs. After the flu, there is an exacerbation of chronic infectious diseases and other pathologies.
The prognosis is generally favorable, but becomes serious in severe hypertoxic and complicated forms of the disease.

Diagnosis of influenza

The main symptoms of clinical diagnosis of influenza are the acute onset of the disease with a rapid increase (within 24 hours) of body temperature to 38-40 ° C, headache, especially in the frontotemporal region, superciliary ridges, pain in the eyes, hyperemia and slight swelling of the face, etc. "Injection of the sclera, bright hyperemia, granularity and dilation of the vessels of the mucous membrane of the soft palate and the posterior wall of the pharynx, the presence of catarrhal manifestations on the 2-3rd day of the disease, a dry unbearable cough, unchanged liver and spleen, leukopenia with relative lymphocytosis.

Specific diagnosis of influenza

The material for isolating the virus is swabs from the nasopharynx, which are used to infect (mainly) chicken embryos as quickly as possible. For the purpose of express diagnostics, an immunofluorescent method is used - processing smears of the mucous membrane of the inferior turbinate with labeled antibodies to detect the virus in epithelial cells.
Serological diagnosis applied as a retrospective one. In practice, the hemagglutination inhibition reaction (HAI) has acquired the greatest importance, which has recently been replaced by more sensitive and promising methods (RIGA, ELISA). To establish an increase in antibody titer (at least 4 times), reactions should be carried out over time (paired sera). The first serum is obtained no later than the 3rd day of illness, and the second - after 7-10 days.

Differential diagnosis of influenza

The diagnosis of influenza, especially during an epidemic, is a fairly commonplace occurrence. Mistakes in the direction of overdiagnosis of influenza often lead to serious consequences due to the delay of adequate assistance. This applies primarily to acute infections (typhoid, meningococcal disease, measles, meningitis, encephalitis, leptospirosis, viral hepatitis, etc.), in which an acute onset and fever with significant toxicosis are also possible. In addition, one should take into account the possibility of exacerbation of chronic or development of acute inflammatory processes (pyelo-glomerulonephritis, pneumonia, appendicitis, pancreatitis, etc.), with an atypical course they can be mistaken for the flu.
The typical form of influenza is quite easy to distinguish from other acute respiratory diseases (ARI). None of them has such an acute onset and severe course with toxicosis. With all acute respiratory viral infections, the main symptoms from the first day are signs of local damage and catarrhal manifestations. Erased forms of influenza are diagnosed more often based on the epidemiological situation in a given area, and during the inter-epidemic period they are often diagnosed as GLC.

Flu treatment

Etiotropic drugs include interferon, rimantadine, donor immunoglobulin with an increased titer of anti-influenza antibodies, oxolin. In the first 1-2 days of illness, rimantadine is prescribed 0.05 g 3 times a day. It is believed to be effective against the influenza A virus. Remantadine is contraindicated in children and people with kidney pathology. Oxolinic ointment (0.25%) is used intranasally in the first days of illness. Leukocyte interferon is effective during the first day of illness. It is prescribed 3-4 drops into the nose 4-6 times or by inhalation 3-4 times a day. Donor anti-influenza immunoglobulin is used for severe forms in a hospital setting, 3-6 ml intramuscularly.
The volume and intensity of treatment for influenza depends on the severity of the disease, the presence of complications and concomitant diseases.
In the case of a mild form, isolation, release from work (study) and treatment at home with “home” remedies is enough - taking a large amount of liquid in the form of strong raspberry tea, juices, a mustard foot bath.
Patients with moderate and severe forms are prescribed bed rest; adults are recommended to take at least 2-3 liters of liquid per day in the form of tea, juices, three times a day, 1-2 antigrippin powders (a drug that contains 0.5 g of acetylsalicylic acid) in addition to the usual diet. acid, 0.3 g of ascorbic acid, 0.02 g of diphenhydramine, 0.02 g of rutin, 0.1 g of calcium lactate) and 0.5 g of mefenamic acid. In addition, medicines and tablets with an antitussive and expectorant effect, mustard plasters on the chest, non-narcotic analgesics, and multivitamins are prescribed. Treatment of patients with influenza encephalitis is, in principle, no different from treatment for other types of encephalitis of viral etiology.
Treatment of patients with influenza pneumonia should be carried out as for bacterial pneumonia (antibiotics, cardiac glycosides, anti-inflammatory and desensitizing agents), taking into account individual pathogenetic characteristics. Caution should be exercised against the use of cupping due to the possibility of hemorrhagic syndrome.
Stenosing laryngotracheitis requires urgent measures to eliminate inflammatory-allergic swelling of the laryngeal tissue, sometimes intubation. Inhalation of coarse aerosols with a temperature of about 40 ° C is used. In no case should antibiotics, sulfonamides and enzyme (protein) drugs be used in inhalation. It is very important to calm the child; for this you can use tranquilizers and sleeping pills. Glycocorticosteroids and hyposensitizing drugs are also prescribed.
In case of bacterial complications, antibacterial drugs are used and local treatment is carried out depending on the nature of the pathology. The widespread practice of prescribing antibiotics and sulfa drugs to prevent bacterial complications is not justified and is even harmful.

Flu prevention

Fighting influenza is a complex and diverse task. It is now unrealistic to talk about the eradication of influenza, but due to the dissemination of knowledge about this disease and the application of vigorous preventive measures, a significant decrease in the intensity of epidemics has been observed.
Isolating sick people is not always an effective means of preventing the spread of the disease. Individual prevention is of great importance. The use of gauze bandages (masks), various types of respirators, and avoidance of situations in which the likelihood of infection increases significantly (using public transport, visiting entertainment venues, meetings, etc.) reduce the number of cases of the disease.
In case of contact with a patient with influenza, it is recommended to use rimantadine 0.05 g per day for 2-7 days, 0.25% oxolinic ointment in the nose, leukocyte interferon (nasal drops or inhalations 4-6 times a day). Wet cleaning, ventilation, and UV irradiation neutralize the virus.
During the influenza epidemic, it is necessary to limit the number of events associated with crowds of people in enclosed spaces, quarantine for children's institutions, hospitals, and the maximum provision of medical care at home.
For specific prevention of influenza, many types of vaccines (live and killed) have been developed for oral, intranasal and parenteral administration, which are quite effective in controlled experiments.
The difficulty lies in organizational and technical issues:
1) the need to anticipate the antigenic variant of the virus will prevail in the epidemic,
2) preparing a sufficient amount of vaccine, 3) immunizing in a short time at least 20-30% of the population (primarily active, in large work groups).
The results of mass immunization with influenza vaccines indicate a significant (2-3 times) decrease in the number of cases and a decrease in the number of severe forms and complications.

Influenza is an acute viral disease that affects millions of people every year. Influenza is caused by three types of viruses - A, B, C. Influenza A is the most common, but influenza B should not be underestimated. In the WHO forecast of the circulation and relevance of influenza viruses for each epidemic season, type B viruses are almost always present. The upcoming 2017-2018 season is no exception. In it, two strains of influenza A virus and one strain B can cause an epidemic outbreak.

Symptoms of influenza B

The disease develops acutely. It all usually starts with an increase in body temperature (up to 38 and even 39 degrees). In addition to fever, patients may be concerned about:

• severe weakness, weakness, malaise;
• , bones, joints;
• redness of the eyes, discomfort in the eyeballs;
• sensations of dryness and burning in the nose and throat.

After 1-2 days, the following manifestations of the disease are added:

• dry sweltering (may be barking);

Influenza B lasts on average 5-7 days. If the patient’s immunity is weakened or if he ignores the doctor’s recommendations (self-medicates, goes outside and to work with a fever, etc.), complications may develop (they are presented in accordance with the frequency of occurrence - from the most common to the rarest) :

Features of influenza B

The clinical picture of influenza B is very similar to influenza A. However, some features can be distinguished in it (comparison with influenza A):

• The numbers to which the patient’s body temperature rises are lower, but in general the fever lasts longer.
• Patients often suffer from pain in the head, muscles and joints.
• Cough, runny nose, sore throat are short-lived.
• Complications develop less frequently.

Of course, based on these features, the doctor cannot accurately determine that the patient has Influenza B. Moreover, an accurate diagnosis of “Influenza” can only be made based on the results of virological studies. Therefore, during an epidemic, any cold should be treated as a flu and be sure to seek medical help and in no case self-medicate.

Treatment of influenza B

Treatment tactics for influenza B include:

• , which allows you to reduce the symptoms of the disease and the risk of complications - bed rest, drinking plenty of fluids, a light diet, antipyretic drugs, multivitamin complexes, vasoconstrictor nasal drops, expectorants, topical medications, etc.
• Specific therapy– purpose of and inducers (stimulators of synthesis) of interferons.

In most cases, patients need basic therapy (many studies confirm that the use of antiviral drugs and interferon does not significantly affect the overall duration of the flu). If the disease is severe, if the patient is weakened, or if he is at risk of developing complications, the use of specific therapy is advisable. Oseltamivir is considered the most effective drug for this disease, but rimantadine, which is often used to treat influenza A, is ineffective. This, by the way, is another distinctive feature of influenza B.

Patients with mild to moderately severe influenza B can be treated at home. A prerequisite for such treatment is to call a therapist and follow his recommendations.

Prevention of influenza B

There are several ways to protect yourself from influenza B. The most effective of them is. It must be done before the epidemic rise in incidence - before December. But since flu vaccines appear in medical institutions no earlier than September-October, the time period for vaccinations is reduced to 2 months - October-November. It’s also worth noting that to get truly effective protection against influenza B, you need to get vaccinated every year.

In addition to vaccination, there are other B measures. All of them are not specific, since they imply a special model of behavior that makes it possible to prevent various respiratory viral diseases. Such preventive measures include:

• Minimizing visits to public places.
• Avoid contact with sick people.
• Frequent hand washing. On the road and in public places, it is advisable to have wet wipes or a special disinfectant spray with you, since it may not always be possible to wash your hands.
• Daily ventilation of premises.
• Regular wet cleaning.

In addition, it is important to increase the body's natural resistance to infections. To do this, first of all, you need to become an adherent of a healthy lifestyle. Cigarettes, alcohol - all this kills ours. Another important link in maintaining health is a balanced diet. Don't forget about sleep and proper rest. Exhausted by work, the body simply cannot be healthy and strong.

And finally, it is worth mentioning one more preventive measure - moisturizing mucous membranes. If the mucous membranes are dry, secretory immunoglobulins, which are part of the local immunity of the respiratory tract, disappear from their surface. Therefore, it is extremely important in winter to use special nasal sprays with sea water or simply rinse your nose with a salt solution. This procedure is considered most effective before going outside. Although after visiting public places, it also doesn’t hurt to moisturize and cleanse the mucous membranes of the respiratory tract.

Zubkova Olga Sergeevna, medical observer, epidemiologist

Flu -acute infectious disease of the respiratory tract caused by the influenza virus, part of the group of acute respiratory viral infections (ARVI). In terms of frequency and number of diseases, influenza and ARVI rank first in the world, accounting for 95% of all infectious diseases. The mortality rate from this disease, sadly, remains high; 2 million people die from influenza every year worldwide. In our country, annually per 100 thousand population there are 2.7 deaths among children and 80 deaths among people over 65 years of age.

In most cases of influenza, the disease is caused by influenza viruses of types A, B, C.

Frequency of epidemics.

Influenza A virus

Influenza A virus is dangerous for both humans and animals, causing epidemics of moderate to severe severity. Each animal species has its own virus that does not spread to other species: that is, as a rule, the avian virus affects only birds and cannot infect pigs, and vice versa. But since this type is constantly changing, there is a great danger for people.

The A2 virus spreads among already infected people.

There are several subtypes of type A virus, classified by surface antigens - hemagglutinin and neuraminidase, for example H1, H5, H7 and H9. Currently, 16 types of hemagglutinin and 9 types of neuraminidase are known. H5 and H7 are lethal.

The recent outbreak of the influenza A(H1N1) bird flu virus has greatly worried both health professionals and society as a whole, and these worries are not in vain, because more than half of people infected with H5N1 have died. To date, most cases of H5N1 disease have been reported in Asian countries among people who have close contact with farmed birds. It is transmitted by airborne droplets, airborne dust and contact, including by eating undercooked poultry.

Another subtype of the type A virus - H1N1 - swine flu is transmitted through contact with a sick animal, from person to person by airborne droplets, as well as through eating meat without sufficient heat treatment. In Moscow, for example, in 2009, 34 cases of human infection with the influenza virus, confirmed by research, were officially registered. In total, 55 cases of swine flu have been recorded in Russia. one third of whom were children from 3 to 17 years old who came from countries popular for holidays: Great Britain, Spain, Thailand, Vietnam, Turkey, Cyprus, the Dominican Republic and other countries.

Influenza B virus

Influenza virus type B spreads only among people and causes a less severe reaction than type A, practically not causing severe epidemics, but like influenza virus type A, it is capable of changing its antigenic structure.

Influenza virus type C

The most harmless type of virus (although in our time it is difficult to predict anything) does not cause severe symptoms or epidemics. It has been little studied. Like virus B, it infects only humans. Contains one surface antigen and 7 nucleic acid fragments. Symptoms of the disease are usually very mild or do not appear at all. It does not cause epidemics and does not lead to serious consequences.

Annual epidemics

The constant modification of the types of influenza viruses adds a lot of trouble to doctors and medical specialists in modernizing vaccines. Each influenza vaccine contains three influenza viruses: one type A virus (H3N2), one type A virus (H1N1), and one type B virus, of course the composition of the vaccines changes annually depending on scientific observations and international estimates. The opinion that vaccination is pointless due to the impossibility of predicting which influenza virus will progress at a particular time is very erroneous; annual vaccination is the best guarantee that your body will create immunity to new strains, because as Hippocrates said: “ Life is short, the path of art is long, opportunity comes quickly, experience is deceptive, judgment is difficult. Therefore, not only the doctor himself must use everything that is necessary, but also the patient and those around him, and all external circumstances must contribute to the doctor in his activities.”.

Be healthy and happy!

Almost 95% of infectious diseases are acute respiratory viral infections, one of which is influenza. Influenza epidemics occur almost every year, usually in the fall and winter, and more than 15% of the population is affected.

Immunity after the flu does not last long, and the presence of various forms of the virus leads to the fact that a person can suffer from this infection several times during the year. Every year, more than 2 million people die due to complications from the flu. Let's find out everything about this disease in this article.

Etiology of influenza

Influenza is caused by a group of viruses belonging to the Orthomyxoviridae family. There are three large genera - A, B and C, which are divided into serotypes H and N, depending on which proteins are found on the surface of the virus, hemagglutinin or neuraminidase. There are 25 such subtypes in total, but 5 of them are found in humans, and one virus can contain both types of proteins of different subtypes.

Influenza viruses change very quickly; every year new types are discovered with changed properties. Sometimes such pathogenic subtypes appear that epidemics caused by them are described in history textbooks. One of these subtypes is “Spanish Flu,” which often killed a person within 24 hours and claimed the lives of 20 million people at the beginning of the last century.

The most dangerous epidemiologically are influenza A viruses; they cause epidemics every year. Type B virus can also cause severe influenza, but it does not spread as widely and outbreaks usually occur during or shortly before type A. Both groups contain proteins H and N, therefore, when classifying them, not only the group, but also the subtype, as well as the place of discovery, year and serial number are indicated. Influenza C virus does not contain the H protein and is usually mild.

How does flu infection occur?

Infection usually occurs through airborne droplets, although contact and household transmission is also possible. The virus enters the body through the mucous membranes of the upper respiratory tract. It is believed that you can become infected with the flu even at a distance of 2–3 meters from a patient, so personal protective equipment becomes especially important during epidemics.

On human skin, the influenza virus dies quickly - after 4–6 minutes, but on household items, the ability to survive increases, for example, on metal and plastic. If a person touches a surface contaminated with the flu virus and then touches their face, and studies show that people touch their face more than 300 times during the day, this dramatically increases the likelihood of infection.

How long a person with the flu is contagious depends on the type and severity of the illness, but you can usually become infected within 5-6 days of the onset of the disease. Moreover, infection can also occur with the erased form of influenza. Infection is facilitated by a decrease in air humidity in the room. Fresh air prevents the virus from entering the respiratory tract, but at low temperatures, about 0 °C, against the background of hypothermia of the mucous membranes and dry air, the risk of contracting the flu increases.

For the spread of infection, it is important at what temperature the influenza virus dies. Different strains react differently to temperature changes, but heating above 70°C kills the virus within 5 minutes, while boiling almost instantly. The virus can remain viable on household items for up to 7 days. High humidity also contributes to its death.

Clinical picture and severity of the disease

From the moment of infection until the first symptoms of the disease appear, it can take from three hours to three days, usually the incubation period lasts 1–2 days. The disease begins acutely, the first signs of influenza are a sharp rise in temperature and symptoms of intoxication. The patient may complain of general weakness, headache, and muscle pain. A runny nose and cough often occur; this condition lasts for 3–4 days, then, if there are no complications, the symptoms gradually decrease.

There are 3 degrees of severity of the disease.

With uncomplicated influenza, symptoms gradually decrease from 3–4 days of illness; by 7–10 days the patient recovers, but general weakness and fatigue may bother him for 2 weeks.

Flu symptoms

The first symptoms of influenza are subjective: weakness, weakness, body aches. Then a sharp increase in temperature occurs and symptoms of intoxication of the body appear. The patient's complaints can be divided into several groups:

• symptoms of intoxication;
• catarrhal phenomena and damage to the upper respiratory tract;
• abdominal syndrome.

Intoxication is expressed by headache, muscle pain, general weakness, and fever. How long the temperature lasts during influenza often depends on the serotype and general immunity of the body. Its increase is accompanied by chills and increased sweating. High temperatures over 39 °C are dangerous as they can lead to seizures and swelling of the brain. Patients with high fever due to intoxication may experience delirium and hallucinations.

The temperature continues for 2–4 days, then it decreases, and the patient gradually recovers. If the temperature lasts longer, or occurs again on the 5th–6th day, this indicates the addition of an infection and the development of complications. In such cases, you should immediately consult a doctor.

In young children, a high temperature is more dangerous not only because of the possibility of developing seizures and cerebral edema; a child with a fever very quickly loses fluid due to sweat. And when abdominal symptoms also occur (nausea, diarrhea, vomiting, abdominal pain), fluid loss becomes even greater, and dehydration occurs. Therefore, treatment of severe influenza in children is usually accompanied by the administration of infusion solutions.

When treating influenza at home, special attention should be paid to the drinking regime. You need to drink as much juice and tea as possible, and if symptoms of dehydration appear, such as dry skin and mucous membranes, especially noticeable on the tongue, consult a doctor immediately.

Objective symptoms of influenza in humans are often not expressed, except for temperature, you may notice pale skin, redness of the pharynx, and hyperemia of the mucous membrane of the eyes. There are types of infection that occur without a runny nose, but even with “dry” flu, there is often a dry, sore throat. The cough is initially dry, then it can become wet; in people with chronic lung diseases (bronchitis), the virus causes an exacerbation of the process.

Treatment

Treatment of influenza in adults and children follows the same principles, but the likelihood of complications in children and the elderly is much higher. This is due to decreased immunity. In older people, it decreases due to the aging of the body and a decrease in reparative processes. In childhood, immunity is still developing, which often leads to various diseases.

Antiviral drugs

Treatment for infection should begin as early as possible. This also applies to antiviral drugs for influenza, which are practically useless to take already on the third day of illness. Therefore, at the first symptoms, or even better before they appear, when there was contact with a flu patient, you need to take an antiviral drug, for example, amantadine (Midantan), Rimantadine, Tamiflu; interferon preparations (“Interferon”, “Aflubin”). This allows you to prevent illness or shorten the duration of illness by 1–3 days.

Taking antiviral drugs for influenza will not only help shorten the duration of the disease, but also prevent the development of complications, so they should be used in people with reduced immunity. Antiviral drugs are also used to treat complications.

Mode

When treating the disease, it is important to adhere to bed drinking regime. Bed rest is necessary even for mild flu, since complications often arise precisely due to non-compliance with bed rest. In patients with moderate influenza, bed rest significantly improves the patient's condition. It is advisable to create a comfortable environment, dim light, silence, since bright light and noise often irritate influenza patients.

Bed rest is needed both to limit the patient’s communication and to reduce the risk of infection for others. Caregivers should use personal protective equipment (mask) for prevention purposes.

To reduce the risk of infection, you need to wet clean the room and ventilate it, since high humidity and fresh air cause the death of the virus. Personal items, dishes, linen, and toys for children should be treated with disinfectant solutions or detergents.

Symptomatic therapy

Drugs for the treatment of influenza can be divided into several groups:

Symptomatic treatment means that each type of drug is taken for specific symptoms.

Features of the disease during pregnancy and lactation

The influenza virus can affect the course of pregnancy, this is especially common when a woman becomes infected with it in the first trimester. The likelihood of pathologies in the fetus increases, and since immunity decreases during pregnancy, complications arise more often.

Therefore, pregnant women should try not to become infected:

Even if a pregnant woman does not leave the house, the virus can be brought by those close to her.

If infection has occurred, then you must remain in bed and drink more juices containing vitamins. The lack of vitamins can be compensated for with medications. It is advisable for pregnant women to take antiviral drugs.

Treatment of influenza during pregnancy should be carried out under the supervision of a doctor, and medications including medicinal herbs and traditional methods should be used.

Flu is dangerous not only during pregnancy, but also during breastfeeding. In this case, it is important to follow hygiene rules. It is not at all necessary to wean the baby from the breast at this time. Feeding can continue provided that no medications are used that can pass into breast milk and the mother tries to prevent infection of the baby during feeding. You need to use a mask and wash your hands and breasts thoroughly before feeding.

Treatment of influenza during breastfeeding should be carried out with drugs that include natural substances. Now drops against the runny nose are produced, which contain only natural ingredients, and herbal teas against coughs. Treatment during feeding should only be prescribed by a doctor.

Complications

Flu can lead to complications in other organs and systems of the body, and they can develop immediately or as a result of the addition of a bacterial infection. So, a severe form of the disease can be complicated by:

The cause of these complications is the virus entering the bloodstream and spreading throughout the body. If a patient exhibits symptoms such as convulsions, rash, hemodynamic disturbances (drop in blood pressure, abnormal heart rate), loss of consciousness, an ambulance should be urgently called.

Late complications are:

• otitis, sinusitis (frontal sinusitis, sinusitis);
• bronchitis, pneumonia, pleurisy;
• meningitis, encephalitis;
• endocarditis, myocarditis.

Typically, late complications of influenza are associated with the addition of a bacterial infection, which requires antibiotic treatment.

Prevention

The characteristics of this infectious disease, its rapid spread, complications during its course, became the reason for the development of a vaccine against influenza. Children are now vaccinated against many viral infections, and developing a vaccine against influenza should not have been difficult for the pharmaceutical industry.

Unfortunately, it is impossible to develop a universal vaccine, since influenza is represented by different groups and serotypes of viruses. Currently, a vaccine containing group A virus antigens is used for vaccination against influenza. Its timely administration can prevent infection, but since viruses B and C are often detected during an epidemic of virus A, it is impossible to completely exclude influenza disease.

Another problem is the short duration of action of the vaccine. Immunity against influenza does not last long, often protecting against infection for only 6–8 months. Therefore, it is better to vaccinate in the fall, so that antibodies against it circulate in the blood throughout the cold, winter period.

Prevention of influenza in children and the elderly is provided free of charge, since they are at risk, and in them the flu can cause complications leading to death. Vaccination is contraindicated if you are allergic to chicken protein, or if there was an allergic reaction to a previous vaccination.

There are many flu vaccines from foreign and domestic manufacturers on the Russian pharmaceutical market:

In addition to vaccination for prevention, antiviral drugs are used. Which antiviral drug is best to choose to prevent influenza? - the most commonly used products include natural substances. Their use does not cause any adverse side effects in people with weakened immune systems. These include “Arbidol”, “Immunal”, “Kagocel”, “Cycloferon” and others. The development and research of drugs against this infection continues.

Nonspecific flu prevention includes:

• the use of immunostimulating drugs for the prevention of influenza (“Anaferon”, “Immunal”);
• during an epidemic, means of protection against influenza;
• increasing immunity and maintaining hygiene rules.

Antiviral drugs are used daily, according to the instructions (Arbidol, Amiksin, Cycloferon).

The best remedy for the flu is to increase the overall immunity of the body. Immunity is enhanced by hardening and the use of vitamins C. We must not forget about personal hygiene and traditional medicine to prevent infection. So, during a flu epidemic it is recommended:

To summarize, let us recall that influenza is an infectious, contagious disease that can lead to various complications. The likelihood of infection increases in autumn and winter. Children and elderly people who are at risk are most often infected with the flu. Timely vaccination against the most likely serotypes causing the epidemic helps prevent the disease.

Influenza is an infectious disease that causes an epidemic or pandemic every year. This causes great damage not only to human health, but also to the global economy.

Influenza is an acute viral disease that affects the epithelial layer of the mucous membrane of the upper respiratory tract. The disease is caused by an influenza viral infection. Many people call “flu” any illness with a runny nose, fever and cough, but this is not true, because such symptoms can also be caused by other pathogens. You can think specifically about influenza only after its laboratory identification.

All about influenza and its pathogens

Influenza is caused by three types of viruses - A, C and B, which belong to the orthomyxoviruses. Influenza A affects not only humans, but also horses, pigs, dogs, cats, cattle and poultry. The causative agents of influenza B and C are dangerous only to humans.

The main causes of influenza are the entry of the virus into the body and decreased immunity.

Influenza infection is very prone to mutations, especially influenza A. This feature has caused frequent epidemic outbreaks of the disease. The antigenic polymorphism of the pathogen makes it impossible to accurately predict the type of influenza that will cause an epidemic, as well as to develop a single vaccine for mass vaccination of the population.

The influenza virus is unstable in the external environment, as it dies from high temperatures, starting from +50 ° C, and from standard disinfectant solutions. When the influenza virus is exposed to sunlight, it dies within 1-2 seconds. At low temperatures, the influenza virus retains its virulence for a long time.

The sources of influenza B and C can only be people, while influenza A is also spread by animals and birds. Favorable places for the spread of the disease are those where large numbers of people gather - kindergartens, schools, institutes, bazaars, shops, entertainment centers, etc. Pandemics are caused mainly by the influenza A virus. With influenza B, local outbreaks of morbidity occur, which are limited one or two countries. Influenza C is rarely recorded as isolated cases.

Flu affects both males and females equally. Children and the elderly are more susceptible to influenza infection. Epidemics occur mainly in late autumn, winter and early spring. Due to the instability of the influenza virus to ultraviolet rays and high temperatures, people rarely get sick with the flu in the summer.

Every fifth resident of Russia falls ill with the flu every year - that’s 27 million patients. In 5 million people, the disease occurs in a severe form and with complications. In half a million cases, influenza virus infection results in death.

Influenza was first written about in 1403. Since then, humanity has experienced about 18 influenza pandemics. In 1931, American scientists first isolated the influenza virus. After some time, they were able to identify its types - influenza a was isolated in 1933, influenza b in 1936 and influenza c in 1947. With the development of medicine and the advent of drugs to treat influenza, the mortality rate from this disease has decreased, although it remains high.

To make it easier to understand everything about the flu, let's consider the pathogenetic processes that occur in our body after infection with the flu.

The main route of infection with influenza is aerosol (airborne droplets). But he is not the only one. The influenza virus causes symptoms that help it spread - sneezing, watery eyes and coughing. When a patient sneezes and coughs, a large number of viral cells are released into the air, with an aerosol of saliva and sputum. This viral aerosol is inhaled by a healthy person.

A less common way of contracting influenza is through contact. After sneezing or coughing, the pathogen settles on the hands, after which it is transmitted through a handshake or household objects used by a sick person.

The entry points for influenza are the mouth, nose and eyes. The influenza virus accumulates in the mucous membrane of the upper respiratory tract, namely in the cylindrical ciliated epithelium. After which, it multiplies and destroys epithelial cells, mainly the trachea. The immune system, in response to the influenza virus, begins to produce interleukins, tumor necrosis factor, immunoglobulins, and neutrophils, which actively fight the pathogen.

The influenza virus destroys the cell wall and thus passes from cell to cell, after which it enters the blood - the viremia phase. With influenza, microcirculation in the blood vessels of the lungs, heart, nervous system and other organs is disrupted, which leads to increased permeability of the vascular walls, perivascular edema, thrombus formation, and impaired hemostasis. The influenza virus is a pneumotropic virus, as it causes specific viral damage to the lung tissue.

Flu symptoms and signs

Flu symptoms can range from mild, moderate to severe. In the clinical picture of influenza, two syndromes predominate - catarrhal and intoxication.

Influenza A has the most severe course with frequent complications. Group B influenza does not cause a pandemic and occurs in a mild to moderate form and is rarely complicated. Influenza C is mild or asymptomatic. Influenza C is often detected during influenza A epidemics.

Important! The condition of patients is aggravated by the addition of complications, which often cause death of the disease.

Patients experience the following main symptoms of influenza:

How does the flu progress?

During the development of the disease, influenza goes through the following stages:

• the first stage - the period of infection - is the time interval from the virus entering the upper respiratory tract to its introduction into the epithelial cells of the mucous membrane;
• the second stage is the incubation period, which begins from the time the virus enters the body’s cells and lasts until the time when the first symptoms of influenza appear. During this stage, the virus multiplies. The average duration of the period is 1-2 days, but it can be several hours.
  There is such a pattern - the more virus that enters the body during infection, the shorter the incubation period. The state of defense mechanisms is also equally important. The patient is contagious from the first days of the incubation period. Only 6-7 days from the onset of the disease, the virus ceases to be excreted by the patient.
• The pronormal stage is characterized by the appearance of initial signs of influenza. Flu symptoms are not pronounced. The patient feels general malaise, pain in joints and muscles, dry nasal mucosa and eyes, and body temperature may rise to 38-40 °C.
• During the peak stage, the symptoms of influenza are pronounced - high body temperature, runny nose, conjunctivitis, cough, stool disorders, headaches, myalgia and others. If complications occur, the clinical picture of influenza is supplemented by their symptoms.
• Recovery stage. The duration of recovery depends on the presence of complications and concomitant diseases. In mild and moderate forms, they recede after 7-10 days.

What complications can arise from the flu?

With the flu, two types of complications can occur: those associated with the influenza virus and those caused by a layer of bacterial flora.

The first group includes the following:

• viral pneumonia and pulmonary edema;
• meningitis, meningoencephalitis;
• infectious-toxic shock.

The second group includes the following:

• bacterial pneumonia;
• otitis;
• glomerulonephritis;
• sinusitis;
• purulent meningitis;
• sepsis.

Flu diagnostic methods

Important! To make an accurate diagnosis, the examination of the patient must be comprehensive and comprehensive.

Collection of complaints

Influenza occurs acutely, and sometimes instantly. From the first day, the patient is worried about severe intoxication. The combination of intoxication, cough and abdominal pain, diarrhea, and nausea should prompt you to think about swine flu. Dry hacking cough.

At the onset of the disease, the symptoms of influenza are nonspecific, so they are often mistaken for acute respiratory viral disease (ARVI).

Let's look at the differences between the clinical manifestations of influenza and ARVI:

Symptoms		Other acute respiratory infections
Onset of the disease	The flu begins acutely and progresses quickly. Symptoms increase over several hours.	The clinical picture develops gradually.
Hyperthermia	In a couple of hours, body temperature can rise to high levels and last for 3 days. Antipyretics do not always bring relief.	Body temperature rises to a maximum of 38.5, and returns to normal after 2-3 days.
Myalgia, arthralgia, hypersensitivity.	The patient complains of pain in the joints and muscles, severe headaches, body aches, chills, excessive sweating, photophobia, and pain in the eyeballs.	The patient's condition is satisfactory.
Manifestations of catarrhal syndrome	The runny nose is not pronounced, lasts a couple of days or may be absent. The influenza virus can worsen chronic sinusitis. Redness of the mucous membranes of the eyes.	Catarrhal symptoms are pronounced with profuse lacrimation, rhinitis, and sneezing.
Pharyngitis, sore throat.	The tonsils, soft palate and back of the throat are red. The “paving stone” symptom is hypertrophy of the follicles of the posterior pharyngeal wall and its hyperemia.	Throat hyperemia. The “paving stone” symptom is not typical.
Lymphadenopathy	Lymph nodes are of normal size.	Lymph nodes are enlarged.
Cough	After a couple of days, a dry cough appears, which eventually becomes wet. The severity of the symptom depends on the type of influenza virus.	A dry cough is present early in the disease and is caused by mucus flowing from the nose into the larynx and trachea.
Manifestations of dyspeptic disorders	Nausea, vomiting, diarrhea.	Not observed.
Duration of the disease	The acute phase lasts 7-10 days and residual effects last up to 3 weeks.	5-7 days without residual effects.

Collecting anamnesis of illness and life

A carefully collected anamnesis and complaints are half of the finished diagnosis. It is imperative to clarify whether the patient has had contact with a person who had signs of the flu (cough, runny nose, pain in the joints, muscles, fever, etc.). And also find out if he has moved from a region where there is a flu epidemic. Ask about any concomitant diseases.

Objective examination

When examining the patient, you can identify redness and enlargement of the follicles of the back wall of the pharynx - “paving stone symptom”, hyperemia and shine of the mucous membrane of the eyes, blush on the cheeks.

With the development of inflammation in the lungs, you can first listen to hard vesicular breathing, then dry rales, and when sputum appears, moist rales of varying sizes.

Laboratory examination

A complete blood count will not always be informative, but sometimes there may be an increase in the number of white blood cells and erythrocyte sedimentation rate, as well as a decrease in the number of lymphocytes.

Identification of the influenza virus is carried out using the following methods:

Instrumental diagnostic methods are carried out mainly to identify complications. An X-ray examination of the lungs is mandatory to confirm or rule out pneumonia.

Flu treatment

Influenza is generally treated under the supervision of a doctor at home. The choice of place of treatment depends on how the flu progresses, the age of the patient and the presence of concomitant diseases. A severe form of influenza and the development of complications are a direct indication for hospitalization of the patient in a hospital.

In the treatment of influenza, the following principles are adhered to:

1. Maintain bed rest during fever.
2. Use of effective antiviral drugs – Tamiflu, Oseltamivir or Remantadine.

Pay attention! The choice of drug and its dosage should be made only by the attending physician. Do not self-medicate, because you can harm your health.

1. Prescription of antipyretic drugs at body temperature above 38.5 °C. If the patient’s condition allows and the temperature is below this figure, you can refrain from taking antipyretics. Hyperthermia indicates the independent production of antibodies aimed at fighting the influenza virus. The drugs of choice may be Aspirin, Paracetamol, Ibuprofen and others.

Important! The use of aspirin in childhood is contraindicated, as Reye's syndrome may occur.

1. Drinking plenty of warm drinks will help cope with intoxication. Teas with raspberries, honey, rosehip, hawthorn decoction, herbal teas, fruit drinks, compotes, mineral water, electrolyte solutions are perfect - Regidron, Humana and others.
2. Gargling is used to treat pharyngitis and sore throat. Chlorophylliptom, solution Lugol, Miramistin, Yox, solution of soda, salt and iodine.
3. When bacterial complications occur, there is a need to prescribe antibacterial agents. Antibiotics are used Cephalosporins, Penicillins, Macrolides and Fluoroquinolones. Only a doctor can choose an effective and safe antibiotic.
4. The daily diet should be complete and balanced, with a sufficient amount of vitamins and microelements.
5. In severe cases, detoxification therapy with intravenous infusions is prescribed Hemodesa, Reopoliglucin, saline and vitamin solutions. If necessary, carry out forced diuresis.
6. To relieve symptoms of intoxication, antihistamines are prescribed, such as Suprastin, Citrine, Tavegil etc.
7. When coughing, use cough suppressants - Lazolvan, ACC.
8. To eliminate a runny nose, you can use nasal drops and sprays ( Nok-spray, Nazivin, Humer and others).

Flu prevention

In order to prevent illness from influenza, specific and nonspecific prophylaxis is carried out.

Specific prevention- this is the formation of immunity against influenza by introducing into the human body a vaccine against the influenza virus, which protects against influenza B, strains A/H1N1 and H3N2 of influenza A. Many people are afraid of vaccination, as they think that it can cause the flu. Vaccination cannot cause influenza because the vaccine does not contain the whole virus, only its antigens. Immunity develops over a period of 12 months, so vaccination must be carried out every year. Unfortunately, specific prevention is not guaranteed protection against influenza, but the disease occurs in a milder form than in unvaccinated people.

TO nonspecific prevention You can list the use of antiviral and immunostimulating drugs at the beginning and during the flu epidemic. The most popular drugs are the following: Kagocel, Arbidol, Anaferon, Viferon, Tamiflu, Lavomax and others.

What flu prevention measures can you take on your own?

• Wash your hands regularly with soap, and it is best to treat your hands with hand disinfectants after visiting public places, which can be purchased at any pharmacy or supermarket.
• Strengthen your health through sports and proper nutrition. Quitting bad habits and alcohol abuse.
• Adequate sleep and rest.
• Taking vitamin supplements, especially ascorbic acid.
• Avoid contact with people with respiratory illness or public places during a flu epidemic.
• Use a mask or respirator when in contact with sick people.
• Rinse the nasal mucosa with saline solutions after visiting public places.
• Avoid hugs, kisses and handshakes during flu epidemics and pandemics.
• If you experience flu symptoms, stay home and isolate yourself from other people.

At the slightest suspicion of influenza, immediately consult an infectious disease doctor for medical help. The outcome of the disease will be favorable with timely and correct treatment.