Patient description: A 17 year old boy complains of vomiting, non-bloody diarrhea, abdominal pain, fever, chills and loss of appetite for the past 3 days. He ate a salad at a restaurant prior to his diarrhea onset. Physical exam was remarkable for pallor, jaundice, and diffuse abdominal tenderness. Lab results were as follows: Hemoglobin: 9.7 g/dL Platelet: 110,000 /cu.mm Creatinine: 3.6 mg/dL blood urea nitrogen (BUN): 73 mg/dL direct bilirubin: 2.4 mg/dL lactate dehydrogenase (LDH): 881 IU/L (normal: 110-265 IU/L) Peripheral blood smear showed a moderate number of schistocytes and helmet cells. Shiga-like toxin-producing E. coli (STEC) stx1/stx2 were found in stools. He has no other underlying disease and he is not on any medications.

Clinical trial eligibility criteria: eligible ages (years): 0.0-18.0,  Respiratory Infections in Children Signed informed consent 2. Male and female patients. 3. The age of the child at the time of first intranasal administration of drug for age group 1: 12 years to <18 years; for age group 2: from 6 years to <12 years; for age group 3: from 2 years to <6 years; for age group 4: 7 months to <2 years; for age group 5: from 0 months to 6 months. 4. Outpatient and inpatient patients hospitalized for epidemiological reasons, with a diagnosis of acute respiratory infection of the upper respiratory tract of mild to moderate severity. (ICD 10: J00 J06 Acute respiratory infections of the upper respiratory tract). 5. The positive result of the enzyme immunoassay express test for pathogens of acute respiratory infection of the upper respiratory tract on screening. 6. At least one episode of body temperature up to 38C and above within 48 hours prior to screening. 7. Presence of at least one of the following mild to moderate symptoms at screening: headache, weakness/malaise, muscle pain/aching, feeling of heat/chills. 8. The duration of the disease is not more than 48 hours at the time of screening according to the patient/parents/adoptive parents. 9. Adequate contraceptive methods during the study for the patients with childbearing potential  Positive express test (in urine) for pregnancy in patients with childbearing potential (menarche). 2. Individual intolerance or hypersensitivity to any of the components of the drug according to the medical history. 3. Taking any drugs with immunomodulatory effect less than 30 days before screening according to medical history. 4. The presence of complications of acute respiratory infection of the upper respiratory tract, signs of severe disease at the time of screening (fever more than 39ºC, febrile convulsions). 5. Acute infectious diseases: diphtheria, measles, infectious mononucleosis, herpes type 1 and 2, rubella, scarlet fever, acute BGSA-tonsillopharyngitis at the time of screening or 30 days before screening. 6. Chronic diseases of the respiratory system (Bronchial asthma, COPD). 7. HIV infection, chronic viral hepatitis B or C (according to history). 8. Impaired renal function with serum creatinine level more than 1.5 times higher than the upper limit of the normal range. 9. Severe liver failure or active liver disease (including viral hepatitis B or C) and increase of ALT and AST more than 5 times of upper limit of the normal range. 10. Participation in any clinical trials and / or taking an experimental drug within 30 days prior to the screening visit. 11. Other significant diseases and conditions of the patient, including mental and physical diseases