Acute respiratory disease features acute cataracts of the upper respiratory tracts. They are characterised by general intoxication and primary affection of the respiratory tracts. They belong to the antroponosis group featuring an airborne transmission mechanism. The disease often affects children. There can be sporadic cases and epidemic outbreaks. The acute respiratory disease can be caused by a great number of (in excess of 200) different etiological agents, such as: 1) influenza viruses of different antigenic types and variants, 2) parainfluenza viruses - four types, 3) adenoviruses - 32 types, 4) reoviruses - three types, 5) rhinoviruses - over 100 types, 6) coronaviruses - four types, 7) the respiratory-syncytial virus, 8) enteroviruses - about 70 types, 9) the simple herpes virus, 10) micoplasms, 11) streptococci, staphylococci and other bacterial agents. Different departments of the respiratory tract can be used as the gate of the infection where inflammatory changes arise. Such changes are exemplified by moderately expressed symptoms of general intoxication, predominant affection of the upper departments of the respiratory tract and benign progress. Localisation of the most expressed changes in the respiratory tract depends on the kind of the originator the patient has been affected by. For example, rhinoviral diseases are characterized by the prevalence of rhinitis. In case of adenoviral diseases, nasopharyngitis prevails. Parainfluenza primarily affects the larynx, influenza - the tracheas and the respiratory-syncytial virus - the bronchial tubes. Besides affecting the respiratory tract, some etiological agents may cause other symptoms as well. Adenoviral diseases may be accompanied by conjunctivas and keratites. Enteroviral diseases may reveal the symptoms of epidemic myalgia, herpangina and exanthema. If not complicated by pneumonia, the acute respiratory disease may last during the period varying from 2-3 to 5-8 days. Pneumonia may delay recovery, with the disease taking up to three to four weeks to cope with.