Background. Group A beta-hemolytic streptococcus (Streptococcus pyogenes) is a widespread bacterial pathogen that can cause many clinical variants of diseases in humans and be a trigger factor for the development of various autoimmune conditions. The purpose of the study was to show the current state of infection caused by group A beta-hemolytic streptococcus in adults and children using case studies. Materials and methods. The article describes 5 cases of streptococcal infection caused by Str.pyogenes with different clinical symptoms. The streptococcal etiology was confirmed by bacteriological method, the levels of ASLO antibodies were evaluated by biochemical method, clinical and biochemical studies were performed to determine markers of organ dysfunction. Results. The paper presents cases of severe streptococcal infection, which occurred in the form of phlegmon (single or multiple), multiple fasciitis of various localizations, development of destructive pneumonia, which was complicated by pneumothorax and pyopneumothorax, streptococcal septic shock, as well as epidermolysis syndrome (“scalded skin” syndrome). Conclusions. There has been a significant increase in the incidence of diseases caused by group A beta-hemolytic streptococcus. This outbreak is characterized by a severe course of infection with the development of various clinical forms with skin and soft tissue damage, destructive pneumonia, and septicemia. All cases are caused by antibiotic-resistant strains.