The study will collect the information on clinical effects and safety of the basic therapy of acute respiratory viral infection (ARVI) + Cycloferone® and basic therapy of ARVI1 + Arbidol® in real-life clinical settings.

Inclusion Criteria:

1. Male and female patients aged from 18 to 65 years.

2. According to the routine clinical practice, a patient is scheduled to receive the treatment as per one of the following regimens:

   - Basic therapy of ARVI1 + Cycloferone®.

   • Basic therapy of ARVI1 + Arbidol®.

3. Presence of symptoms of ARVI:

   • Presence of two and more symptoms of moderate severity or three and more mild symptoms in accordance with the WURSS-21 questionnaire;
   • Presence of two and more symptoms of moderate severity or three and more mild symptoms in accordance with the CCQ questionnaire;
   • Presence of hyperthermia episodes ≥ 37.5°С and ≤ 40.0°С from onset of the disease.

1. Male and female patients aged from 18 to 65 years.

2. According to the routine clinical practice, a patient is scheduled to receive the treatment as per one of the following regimens:

   - Basic therapy of ARVI1 + Cycloferone®.

   - Basic therapy of ARVI1 + Arbidol®.

3. Presence of symptoms of ARVI:

   - Presence of two and more symptoms of moderate severity or three and more mild symptoms in accordance with the WURSS-21 questionnaire;

   • Presence of two and more symptoms of moderate severity or three and more mild symptoms in accordance with the CCQ questionnaire;
   • Presence of hyperthermia episodes ≥ 37.5°С and ≤ 40.0°С from onset of the disease.

4. Diagnosis as per ICD-10 (primary diagnosis is one of the below diagnoses):

   - J00 - Acute nasopharyngitis, rhinitis;

   - J02 - Acute pharyngitis;

   - J02.8 - Acute pharyngitis caused by other specified pathogens;

   - J02.9 - Acute pharyngitis, not otherwise specified;

   - J03 - Acute tonsillitis;

   - J03.8 - Acute tonsillitis caused by other specified pathogens;

   - J02.9 - Acute tonsillitis, not otherwise specified;

   - J04 - Acute laryngitis and tracheitis;

   - J04.0 - Acute laryngitis;

   - J04.1 - Acute tracheitis;

   - J04.2 - Acute laryngotracheitis;

   - J05 - Acute obstructive laryngitis (croup);

   - J05.0 - Acute obstructive laryngitis (croup);

   - J06 - Acute infection of the upper respiratory tract of multiple and unspecified localization;

   - J06.0 - Acute laryngopharyngitis;

   - J06.8 - Other acute infections of the upper respiratory tract of multiple localization;

   - J06.9 - Acute infection of the upper respiratory tract, not otherwise specified;

   - J20.4 - Acute bronchitis caused by parainfluenza virus;

   - J20.5 - Acute bronchitis caused respiratory syncitial virus;

   - J20.6 - Acute bronchitis caused by rhinovirus;

   - J20.8 - Acute bronchitis caused by other specified agents;

   - J20.9 - Acute bronchitis, not otherwise specified;

   - J21 - Acute bronchiolitis;

   - J21.0 - Acute bronchiolitis caused by respiratory syncytial virus;

   - J21.8 - Acute bronchiolitis caused by other specified agents;

   - J21.9 - Acute bronchiolitis, not otherwise specified;

   - J22 - Acute respiratory infection of lower respiratory tract, not otherwise specified;

   - B34.0 - Adenovirus infection, not otherwise specified;

   - B34.9 - Viral infection, not otherwise specified;

   - B97.0 - Adenovirus infection;

   • B97.4 - Respiratory syncytial infection.

5. Symptoms of the disease are present for not more than 24 h before inclusion in the study.

6. Patient's written consent for participation in the study.

Exclusion Criteria:

1. The use of other drugs having antiviral and/or immune stimulating and/or immune modulating effect.
2. Positive result of SARS-CoV-2 RNA PCR test.
3. Suspected novel coronavirus infection COVID-19 in accordance with the Temporary Methodical Recommendations of the MoH of RF on Prophylaxis, Diagnostics and Treatment of Novel Coronavirus Infection (COVID-19) (current version at the time of inclusion of patients).
4. Current bacterial infection requiring administration of antibacterial drugs.
5. Active non-respiratory viral infection: meningitis, encephalitis, pneumonitis.
6. Availability of indications for hospitalization.
7. Chronic pulmonary diseases (asthma, chronic obstructive pulmonary disease, cystic fibrosis, pulmonary emphysema, tracheobronchial dyskinesia, bronchiectasis etc.).
8. Pulmonary tuberculosis (active or inactive form).
9. Chronic heart failure of functional classes III-IV according to functional classification of the New York Heart Association (NYHA) including instable progressive angina pectoris of functional class IV, uncontrolled arterial hypertension, severe arterial hypotension, severe arrhythmia requiring the treatment with antiarrhythmic drugs of classes Ia, Ib, Ic or III, myocardial infarction, surgeries on the heart and coronary vessels, transient ischemic attack or stroke, pulmonary embolism or deep vein thrombosis.
10. Psychic diseases, neuromuscular, neurocognitive disorders, history of epilepsy.
11. Decompensated diabetes mellitus.
12. Obesity of degree 2-3 (body mass index ≥ 35.0 kg/m2).
13. Severe decompensated renal and hepatic diseases including cirrhosis (acute/chronic renal/hepatic failure).
14. Thyroid diseases.
15. Stomach and duodenum ulcer or other erosive-ulcerative gastrointestinal disorders in exacerbation stage.
16. Malabsorption syndrome or other clinically significant gastrointestinal disease (uncorrected vomiting, diarrhea, ulcerative colitis and others).
17. Malignant neoplasms.
18. Pregnancy, breast feeding.
19. Hemoglobinopathy.
20. Primary and secondary immunodeficiencies (HIV-infection, use of immunosuppressants, systemic glucocorticoids etc.).
21. Contraindications mentioned in the approved instructions for use of the drugs used in the study.
22. Disease or use of medicines, which, in the doctor's opinion, can influence safety, tolerability and efficiency of the study medicines.

Patients with symptoms of ARVI receiving the therapy at the outpatient stage.