ARVI is the most common children infection: children aged 0–5 years suffer, on average, 6–8 episodes of ARVI per year; and in the 1–2 years of visiting kindergarten the incidence rate is higher for 10–15% than in unorganized children, and at school the latter get sick more often. The incidence of ARVI is the highest in the period from September to April and it amounts about 87–91 thousand per 100 thousand in the population. The respiratory infectious disease protection of the organism is

more »

... out in several stages and at various levels. It primarily depends on a mechanical barrier that prevents entering the virus agent into the organism – the mucous membrane of the nasal cavity, paranasal sinuses and nasopharynx. It can be achieved due to the peculiarities of its structure – respiratory epithelium, mucociliary transport, mucus properties and lymphoid organs associated with mucous membranes. If the pathogen nevertheless penetrates this barrier, then innate immunity starts protection activity, and after that the acquired immunity activates. Antiviral protection has differences due to the structure of the virus, it's extremely small size, and the impossibility of reproduction outside the cells. The formed immune response persists even after elimination of the pathogen in the form of immune memory, which allows a faster and stronger reaction when the pathogen reappears. Children with primary immunodeficiency, genetic, oncological, hematological diseases, bronchial asthma, chronic ENT pathology are a special risk group in terms of the frequency and severity of ARVI and influenza. In this connection, the prevention of the incidence of ARVI and influenza is extremely important.