Respiratory syncytial virus. Respiratory syncytial infection Respiratory syncytial viral infection in children symptoms

Causes

Respiratory syncytial infection is widespread; According to various data, the share of infection cases in the structure of the overall incidence of acute respiratory viral infections ranges from 3 to 16%. Although both children and adults can get sick, the virus is extremely dangerous for young children. Observations have shown that when an infected child appears in a group of children's institutions, all other children under the age of 1 year become ill.

The highest incidence rates are observed in the winter and spring months, but registration of a case of infection is possible at any time of the year. The forms of the disease can be different - there are both lesions of the upper respiratory tract, typical of uncomplicated ARVI, and severe bronchiolitis and pneumonia. Older children and adult patients most often easily tolerate the disease - in contrast to children in the first 6 months of life.

The causative agent of respiratory syncytial infection is a virus belonging to the Paramyxoviridae family. It is called the RS virus, RSV infection and is classified as a group of pathogens that cause ARVI (acute respiratory viral infections) in children and adults. Sensitive to the influence of the external environment, quickly inactivates at a temperature of about 55 ° C (on average in 5 minutes). Contains ribonucleic acid (RNA), causes the formation of syncytium, or pseudogiant cells, in tissue culture.

Respiratory syncytial virus is transmitted by airborne droplets (during coughing, sneezing), through contact and household contact (by shaking hands, using any objects touched by an infected person - for example, toys).

The source of infection is a sick person, and the “entry gate” is the epithelial cells of the upper respiratory tract.

Risk factors for severe MS infection have been identified:

In children under 1 year of age, respiratory syncytial virus causes lung damage with episodes of apnea (stopping breathing).

Pathogenesis

Penetration of the PC virus into epithelial cells leads to their death. Pathological changes also include:

• edema, thickening of the walls of the bronchi;
• necrosis of the tracheobronchial epithelium;
• blockage of the lumen of the bronchi with mucous lumps and epithelium;
• formation of atelectasis;
• formation of immune complexes.

The process is characterized by rapid progression, with a high probability of spreading to the lower parts of the respiratory system.

The RS virus is able to suppress the activity of the interferon system, which slows down the formation of the immune response. Secondary immunodeficiency leads to weakened immune defense and an increased risk of bacterial infection.

Symptoms

The incubation period for infection with respiratory syncytial virus infection lasts from 3 to 6 days. The course of the disease largely depends on age. Adults tolerate RSV infection easily in the form of classic ARVI without severe intoxication. Patients are concerned about:

• weakness, moderate lethargy;
• headache;
• increase in body temperature to 37.5-38 °C;
• nasal congestion;
• sore throat;
• dry paroxysmal cough;
• dyspnea.

A non-productive cough turns into a wet cough after a few days. Even after the fever disappears, it can persist for 3 weeks - this is one of the typical signs of MS infection. As the condition worsens, patients complain of shortness of breath and a feeling of heaviness in the chest.

Bronchiolitis is an inflammatory disease of the lower respiratory system, characterized by damage to the small bronchi and bronchioles. Children under 2 years of age are affected, although in the vast majority of cases bronchiolitis is recorded in patients no older than 9 months. One of the most likely provoking etiological agents is respiratory syncytial virus. Symptoms usually appear a few days after the onset of ARVI (runny nose, fever), the clinical picture includes:

1. Severe weakness, lethargy or agitation.
2. Excruciating headache.
3. Loss of appetite.
4. Fever (37.5-38.5 °C).
5. Spasmodic cough, runny nose, pharyngitis.

Sometimes vomiting and stool upset occur - usually in the first day after the onset of clear symptoms. The patient's breathing is frequent, short, whistling with difficulty exhaling; accompanied by the participation of auxiliary muscles. There is swelling of the chest, a gray-cyanotic tint of the skin, and bluish lips. When auscultating the lungs, you can hear dry whistling and moist rales on both sides. The cough is initially dry and hoarse; after it acquires a productive character, sputum is difficult to separate.

Diagnostics

As a rule, only respiratory syncytial infection in children requires rapid confirmation of the diagnosis. Adults experience it as a normal acute respiratory viral infection without the need for hospitalization in a hospital and making a decision on the tactics of emergency measures. Used:

• general blood analysis;
• chest x-ray;
• pulse oximetry;
• linked immunosorbent assay;
• immunofluorescent method;
• polymerase chain reaction.

The choice of studies is made by the attending physician.

Treatment

Patients are treated on an outpatient or inpatient basis. Hospitalization required:

• children under 6 months of age;
• children with episodes of apnea;
• patients with signs of respiratory failure;
• patients with a need for constant sanitation of the respiratory tract;
• in the presence of severe concomitant pathologies.

It is also recommended to hospitalize children who show signs of malnutrition and feeding difficulties. Social indications are important - the absence of persons who can care for the patient during illness, the patient being in constant contact with other children in orphanages.

When infected with respiratory syncytial virus, treatment includes the following measures:

1. Hydration, that is, drinking plenty of fluids, administering glucose-saline solutions intravenously through a nasogastric tube.
2. Inhaled short-acting B2-agonists (salbutamol).
3. Clearing the nose of mucus.
4. Oxygen therapy according to indications.

Antibacterial therapy is used only if the patient has a proven bacterial infection.

Mucolytics (ambroxol) should not be used without a doctor's prescription, since the volume of bronchial secretions increases and the symptoms of respiratory failure worsen. In addition, the secretion is liquid, and there is no need to further liquefy it.

The feasibility of using glucocorticosteroids, both inhaled and systemic, is discussed. It is not recommended to include vibration massage in the treatment regimen for bronchiolitis due to its low effectiveness.

In case of severe respiratory failure, apnea, mechanical ventilation (artificial ventilation) is used. The need to prescribe ribavirin as an antiviral drug is determined by the doctor.

Prevention

• maintaining breastfeeding for at least the first 6 months of life;
• prevention of passive smoking;
• reducing the frequency and time of stay in crowded places;
• limiting and avoiding contact with persons who have symptoms of ARVI;
• frequent hand washing, avoiding touching your eyes, nose and mouth before performing hygiene procedures.

Children at risk of severe RS infection are immunized with palivizumab (monoclonal antibodies to the RS virus).

The term MS infection defines an acute respiratory viral pathology, which is characterized by predominant damage to the structures of the lower respiratory tract. It has become quite widespread; in the structure of the entire incidence of ARVI (acute respiratory viral infection) it is up to 20%.

The abbreviation RS infection stands for respiratory syncytial infection. The disease is most common among children under 3 years of age. It often affects premature newborns under 3 months of age, and in this case it can have a severe course.

Causes (etiology)

The virus that causes MS infection belongs to the paramyxovirus family. It is characterized by tropism for the cells of the mucous membrane of the lower respiratory tract. The virus contains RNA (ribonucleic acid) as its genetic material. Despite the presence of a protein shell, the virus is quite unstable in the external environment. It quickly dies under the influence of high temperatures (boiling kills the pathogen instantly), as well as disinfectants. The virus remains viable for a longer time at low temperatures, especially if it is in droplets of mucus. The pathogen is transmitted by airborne droplets from a sick person or a virus carrier. It is released with tiny droplets of mucus, and then in the form of an aerosol with inhaled air enters the respiratory tract of a healthy person. A sick person becomes infectious to others even before clinical manifestations of the disease appear.

Mechanism of development (pathogenesis)

The virus that causes MS infection has a tropism for the cells of the mucous membrane of the respiratory organs. After inhaling air with the virus, it settles in the upper respiratory tract, integrates into the cells of the mucous membrane and leads to the development of an inflammatory reaction. It also causes intoxication of the human body due to the absorption of toxic compounds into the blood. After initial reproduction in the cells of the nasopharynx, the pathogen enters the small bronchi and alveoli of the lungs, where it also causes an inflammatory reaction. A feature of the course of MS infection is that the pathogen leads to changes in the morphological and functional properties of cells in the lower respiratory tract. They acquire significant, gigantic sizes, and also connect with each other. The result of structural changes is a narrowing of the small bronchi, impaired drainage function, accumulation of mucus in the alveoli with a significant increase in the risk of subsequent secondary bacterial infection. After an infection, unstable immunity is formed, so a person can get an MS infection several times in his life.

Symptoms

The first clinical signs of the disease usually appear 5-7 days after infection (incubation period). They include mild intoxication with headache, subfebrile body temperature up to +38 ° C, mild chills, aching muscles and joints, general weakness, loss of appetite, decreased ability to work, as well as conjunctivitis (redness of the eyes, burning sensation in them, lacrimation). Then signs of the development of an inflammatory reaction in the respiratory organs appear. Depending on the predominant localization of the pathological process, several clinical forms of the disease are distinguished:

MS infection has a severe course in children under the age of 1 year. The disease is accompanied by significant intoxication, convulsions, diarrhea and vomiting, resulting in a high risk of death. In older children and weakened adults, the disease is often accompanied by the development of bacterial complications in the form of inflammation of the middle ear (otitis media), paranasal sinuses. In this case, the sick person’s condition deteriorates significantly and quite quickly.

Acute otitis media (bacterial inflammation of the middle ear) in children is a common complication of ARVI. This is due to the fact that the Eustachian tube, which connects the nasal cavity and the tympanic cavity, is shorter and has subtle bends. This makes it easier for bacteria to pass from the nose into the ear.

Diagnostics

In most cases, the diagnosis of MS infection is established by an infectious disease specialist based on clinical symptoms during the period of epidemiological rise in incidence. To reliably detect and identify the pathogen, tissue research can be used, in which the test material (nasopharyngeal wash, sputum) is introduced into tissue culture, after which the reproduction of the virus in cells is recorded. It is also possible to perform RSK (complement fixation reaction), which is used to determine the activity (titer) of antibodies to the virus in the blood. These studies are primarily used to conduct epidemiological research to identify the source of infection.

Treatment

Antiviral therapy is not usually prescribed for MS infection. The uncomplicated course of the disease in adults and older children makes it possible to carry out treatment at home. Applicable symptomatic therapy, which includes bed rest, a diet high in vitamins, fiber and carbohydrates, and drinking plenty of fluids (dried fruit compote, tea, still water). If necessary, non-steroidal anti-inflammatory (Paracetamol), antihistamine (Suprastin, Diazolin) drugs are used, which help reduce body temperature and also improve well-being. Taking vitamin C is recommended. Ascorbic acid suppresses the activity of the virus. Children under the age of 1 year, as well as weakened patients with severe MS infection, are subject to hospitalization. The department carries out detoxification (intravenous drip administration of saline solutions, vitamins, hormonal agents), antispasmodics and aminophylline are prescribed, which expand the lumen of the bronchi, facilitate breathing, and also reduce the likelihood of developing bacterial complications. Additionally, antibacterial agents are often prescribed, especially in the case of a confirmed complicated course of MS infection.

In general, the prognosis for MS infection is favorable. The exception is the development of the disease in weakened people, as well as children under the age of one year. To avoid the development of infection, it is important to follow general preventive measures. Vaccination against MS infection has not been developed.

Our expert is the head of the arrhythmology department of the Scientific Research Clinical Institute of Pediatrics, Russian National Research University named after N. N. Pirogov of the Ministry of Health of Russia, vice-president of the Association of Pediatric Cardiologists of Russia Igor Kovalev.

Unusual cold

Respiratory syncytial infection, despite its unfamiliar name, is quite common. Both children and adults can get sick from it during the cold season - that is, from October to May - along with other viral infections: ARVI, para-influenza, influenza, adenoviral... But if the clinical manifestations of influenza, for example, are high fever and damage to the mucous membranes membranes of the upper respiratory tract, then with RSV the lower parts are affected with the frequent development of bronchitis, bronchiolitis and pneumonia in children of the first two years of life.

The bronchial tree at this age is not yet developed, the lumen of the bronchi is small. Under the influence of the RS virus, swelling of the bronchial mucosa occurs, an excess amount of thick sputum is produced, which accumulates and blocks the lumen. While an adult or an older child can cough, very young children cannot do this due to the anatomical structure of the respiratory tract. The baby develops respiratory failure - breathing quickens, the skin becomes pale or blue. Doctors in this case diagnose “bronchiolitis” or “obstructive bronchitis”. Sometimes respiratory failure is so severe that artificial ventilation is required. As a result, this infection, which is not scary for adults, is so severe in children that, as a rule, they have to be hospitalized.

Who gets sick more often

There are a lot of rumors about RSV. One of them is that boys get sick more often than girls. Yes, this is true, but this fact has no significance for the prevention and treatment of the disease. Another myth is that children from families with low social status are susceptible to this disease. In fact, infection does not depend on the level of family income. But it is true that RSV infection is more often diagnosed in large families. Infection always occurs where there is a lot of contact between children.

In fact, RSV can also be contracted by the only child in the family who is regularly taken to kindergarten, educational clubs, and children's performances.

Threat to life

For some groups of children, MS infection can be life-threatening. These are primarily children of the first two years, especially premature ones, born before the 32nd week of pregnancy, who have immaturity of the respiratory tract and lungs. Also at risk are children with cardiomyopathies, congenital heart defects, excess blood flow in the lungs, or heart defects accompanied by cyanosis of the skin. Many experts consider children with Down syndrome, congenital lung anomalies, and neuromuscular pathology to be at risk. All these children need seasonal immunization to prevent MS infection. It is passive, that is, it is not a weakened or killed pathogen that is introduced, as with other vaccinations, but ready-made antibodies that will protect the body from the RS virus.

The use of antibodies to the RS virus as a means of preventing the disease has proven its effectiveness over many years. But unfortunately, this vaccine is not included in the national vaccination schedule, so each region vaccinates its children to the best of their ability at the expense of the local budget. In fact, the prevention of MS infection is a new technology for domestic healthcare and requires the search for additional ways of financing. Because for children at risk this is the only possible protection.

Although, of course, in matters of prevention, one should not neglect the observance of banal precautions: limit the child’s contacts during the cold season, follow the rules of personal hygiene. The latter applies to all family members.

Respiratory syncytial infection (RS infection) is an acute disease of a viral nature, which is characterized by a moderately severe intoxication syndrome, damage to small bronchi and bronchioles with the possible development of their obstruction.

Young children are most susceptible to this infection. However, the disease also occurs in children of older age groups and adults. Sporadic cases of the disease are recorded throughout the year; group incidence increases during the cold period. After an infection, the body develops unstable immunity, so repeated cases of infection are possible.

Causes

The causative agent of MS infection - the same name Vrus - enters the human body mainly through airborne droplets.

The causative agent of the disease is an RNA-containing respiratory syncytial virus from the paramyxovirus family. It is unstable in the external environment and does not tolerate both low and high temperatures.

The source of infection can be a sick person or a virus carrier. Moreover, contagiousness appears 2 days before the first symptoms and can persist for 2 weeks. Infection occurs mainly through airborne droplets, and in the presence of close contact, it is possible through hands and household items.

Development mechanisms

Infectious agents enter the human body through the mucous membrane of the respiratory system. The virus begins to multiply in the epithelial cells of the upper respiratory tract, but the pathological process quickly spreads to the lower respiratory tract. At the same time, inflammation develops in them with the formation of pseudogiant cells (syncytium) and hypersecretion of mucous secretion. The accumulation of the latter leads to a narrowing of the lumen of the small bronchi, and in children under one year of age – to their complete blockage. All this contributes to:

• violation of the drainage function of the bronchi;
• the occurrence of areas of atelectasis and emphysema;
• thickening of the interalveolar septa;
• oxygen starvation.

In such patients, broncho-obstructive syndrome and respiratory failure are often detected. If a bacterial infection occurs, pneumonia may develop.

Symptoms of MS infection

The clinical picture of the disease has significant differences depending on age. After infection, it takes 3 to 7 days for the first symptoms to appear.

In adults and older children, the disease occurs as an acute respiratory infection and has a fairly mild course. General condition, sleep and appetite are not affected. Its characteristic manifestations are:

• increase in body temperature to subfebrile levels;
• non-intensive;
• nasal congestion and slight discharge from it;
• dryness and sore throat;
• dry cough.

Usually all symptoms regress within 2-7 days, only the cough can persist for 2-3 weeks. However, in some patients the patency of the small bronchi is impaired and symptoms of respiratory failure develop.

In young children, especially in the first year of life, MS infection has a severe course. From the first days of the disease, the lower respiratory tract is involved in the pathological process with the development of bronchiolitis. In these cases:

• cough intensifies and becomes paroxysmal;
• breathing rate increases;
• pallor and cyanosis of the skin appears;
• auxiliary muscles are involved in the act of breathing;
• fever and intoxication are moderate;
• possible enlargement of the liver and spleen;
• A large number of moist fine bubbling rales are heard above the surface of the lungs.

If the bacterial flora is activated during this period, the pathological process quickly spreads to the lung tissue and develops. This is evidenced by the deterioration of the child’s condition with high fever, lethargy, weakness, and lack of appetite.

In addition to pneumonia, the course of MS infection can be complicated by false croup, and sometimes by croup.

The disease is most severe in infants who have a burdened premorbid background (rickets, congenital malformations).

Diagnostics

The diagnosis is confirmed by the detection of a high titer of specific antibodies in the patient’s blood.

The doctor can assume the diagnosis of “respiratory syncytial infection” based on clinical data and a characteristic epidemiological history. Laboratory diagnostic methods help confirm it:

• virological (nasopharyngeal swabs are used for analysis to isolate the virus);
• serological (paired blood sera are examined with an interval of 10 days using the complement fixation reaction and indirect hemagglutination to detect specific antibodies; an increase in their titer by 4 times or more is considered diagnostically significant);
• immunofluorescence (carried out to detect the antigen of the RS virus; for this purpose, fingerprint smears from the nasal mucosa treated with a specific luminescent serum are examined).

A blood test reveals a slight increase in the number of leukocytes and an acceleration of ESR, monocytosis, and sometimes a neutrophil shift of the leukocyte count to the left and atypical mononuclear cells (up to 5%).

Differential diagnosis for this pathology is carried out with:

• others;
• mycoplasma and chlamydial infection.

Treatment

In the acute period of the disease, bed rest, a gentle diet and plenty of fluids are prescribed. In the room where the patient is located, it is necessary to maintain optimal microclimate parameters with a comfortable temperature and sufficient humidity.

The following medications are used to treat MS infection:

• (interferon inducers);
• specific immunoglobulin with antibodies to the RS virus;
• in the case of bacterial flora, antibiotics (aminopenicillins, macrolides);
• to reduce body temperature - non-steroidal anti-inflammatory drugs (Paracetamol, Ibuprofen);
• expectorants (Ambroxol, Bromhexine);
• bronchodilators for the development of bronchial obstruction (Salbutamol, Berodual);
• vitamins.

In severe cases, patients are hospitalized in a hospital for intensive care.

With early diagnosis and treatment, the prognosis for recovery is favorable. However, cases of the disease in children of the first year of life, which require constant monitoring of the child and timely adjustment of treatment, are cause for concern.

Which doctor should I contact?

This infection is usually treated by a pediatrician. In more severe cases, consultation with an infectious disease specialist and pulmonologist is necessary, and less often with an ENT doctor.

About MS infection in the program “Live Healthy!” with Elena Malysheva (see from 30:40 min.):