Observational Program, Study the Preventive Efficacy of the BiVac Polio Vaccine Against the Incidence of Acute Respiratory Infections, Including COVID-19

Inclusion Criteria: * Volunteers must meet the following inclusion criteria: * Healthy volunteers aged 18-65 years. * The presence of a written and dated informed consent of the volunteer to participate in the program. * Consent to observe precautionary measures to limit the circulation of the vaccine virus among people around the vaccinated person (personal hygiene, isolation from unvaccinated children and people with immunodeficiency). * Volunteers who are able to fulfill the requirements of the protocol (i.e., fill out a self-observation diary, remember the dates of control visit). Non-inclusion criteria: * COVID-19 infection (including cases of asymptomatic carrier). * Positive test for COVID-19 (PCR). * Vaccination with any live and / or replicative vaccine one month before screening. * Neurological disorders that accompany previous vaccination with oral polio vaccine. * Immunodeficiency condition (primary). * Malignant neoplasms. * Immunosuppression (vaccinations are carried out no earlier than 3 months after the end of the course of therapy). * Pregnancy. * Hypersensitivity to any component of the vaccine. * Strong reaction (temperature above 40°C) or a complication on the previous administration of the drug. * Acute infectious or non-infectious diseases. Vaccinations are carried out 2-4 weeks after recovery or remission. In case of mild acute respiratory viral infections, acute intestinal diseases, vaccinations are carried out after the temperature normali…