Acute respiratory viral infections

SARS - the most common disease, including children. Even in non-epidemic years, the incidence of SARS recorded many times greater than the incidence of all the major infectious diseases. During pandemics for 9-10 months in the epidemic process involves more than 30% of the world population, with children make up more than half of them. Incidence among children of different age groups can vary depending on the properties of the virus that caused the epidemic. However, in most cases, the highest incidence was observed in children aged 3 to 14 years. SARS often occur with complications (addition of inflammatory processes in the bronchi, lungs, paranasal sinuses, etc.) and cause exacerbation of chronic diseases. Transferred SARS usually do not leave behind a stable long-term immunity. In addition, the lack of cross-immunity, as well as a large number of serotypes of pathogens SARS buy zithromax online contribute to the development of the disease in the same child several times a year. Repeated SARS led to a decrease in total body resistance, the development of transient immunodeficiency states, delayed physical and psychomotor development, cause allergy, prevent the carrying out of preventive vaccinations, etc. It is very significant and the economic losses caused by SARS - both direct (treatment and rehabilitation of sick child) and indirect (related to the disability of parents). All the circumstances listed above explain the priority of this issue for the health of any country.

Ill children of any age. The source of infection - a sick man. Ways of transmission - airborne and contact-household (less often). The natural susceptibility of children to SARS is high. Patients most contagious during the 1st week of illness. For SARS is characterized by seasonality - peak incidence occurs in the cold season. After suffering a disease formed type-specific immunity. SARS spread everywhere. Large epidemics of influenza occur in an average of 1 time in 3 years, they usually cause new strains of the virus, but it is possible recycling of similar antigenic composition of the strains after several years of absence. In other etiology of SARS mainly recorded sporadic cases and small outbreaks in children's groups, epidemics are rare.

Often Atrium are upper respiratory tract, eyes and conjunctiva less digestive tract. All agents of SARS epiteliotropny. Viruses are adsorbed (fixed) on epithelial cells, they penetrate into the cytoplasm, where they are subjected enzymatic disintegration. The subsequent reproduction of the pathogen leads to dystrophic changes of inflammatory cells and mucosal reactions at the entrance gate. Each disease of SARS group has distinctive features in accordance with the tropism of certain viruses to certain divisions of the respiratory system. Influenza viruses and RSV, adenoviruses can infect the epithelium of both upper and lower respiratory tract with the development of bronchitis, bronchiolitis, and syndrome of airway obstruction, with rhinovirus infection mainly affected the epithelium of the nasal cavity, while parainfluenza - the larynx. Furthermore, adenoviruses have a tropism for lymphoid tissue and mucosal epithelial cells of the conjunctiva.

A damaged epithelial barriers SARS pathogens penetrate into the bloodstream. Intensity and duration of viremia phase depends on the degree of dystrophic changes of the epithelium, the prevalence of process states and local humoral immunity premorbid background and age of the child, as well as on the characteristics of the pathogen. cellular debris, coming along with the virus in the blood, are toxic and toxic-allergic action. Toxic effects are mainly directed to the central nervous system and cardiovascular system. Because of microcirculation disorders occur hemodynamic disorders in various organs and systems. If you have a previous sensitization may develop allergic and autoimmune reactions.

The defeat of the airway epithelium leads to a violation of its barrier function and promotes the adherence of the bacterial flora with the development of complications.


The incubation period is 2-7 days, averaging 2-4 days. The disease begins acutely with moderate fever, catarrhal symptoms and low toxicity. In the next 3-4 days, the symptoms increase. Body temperature is typically less than 38-38,5 ° C, seldom at this level persisting more than 1 week.

Catarrh of the upper respiratory tract - a constant feature of parainfluenza in the first days of illness. Celebrating dry rough "barking" cough, hoarseness and changes in voice, soreness and pain in the chest, a sore throat, runny nose. Discharge from the nose are sero-mucous. On examination, the patient detect congestion and swelling of the tonsils, palatine arches, the graininess of the mucous membrane of the posterior pharyngeal wall. Often, the first manifestation of parainfluenza in children 2-5 years in favor of croup syndrome. Suddenly, often at night, there are rough "barking" cough, hoarseness, noisy breathing, ie, developing stenosis of the larynx. Sometimes these symptoms appear in the 2-3-day sickness. In young children with parainfluenza may result in not only the upper but also the lower respiratory tract; in this case the picture of obstructive bronchitis. When uncomplicated during parainfluenza disease duration of 7-10 days.