BACKGROUND Patients with immune-mediated diseases, such as juvenile idiopathic arthritis (JIA) and inflammatory bowel disease (IBD) are at increased risk of developing infections, due to disease-related immune dysfunction and applying of immunosuppressive drugs. AIM To evaluate vaccine coverage in patients with IBD and JIA, and compare it with healthy children. METHODS In the cross-sectional study we included the data from a questionnaire survey of 190 Legal representatives of children with JIA ( n = 81), IBD ( n = 51), and healthy children (HC, n = 58). An electronic online questionnaire was created for the survey. RESULTS There were female predominance in JIA patients and younger onset age. Parents of JIA had higher education levels. Employment level and family status were similar in the three studied groups. Patients with JIA and IBD had lower vaccine coverage, without parental rejection of vaccinations in IBD, compare to JIA and healthy controls. The main reason for incomplete vaccination was medical conditions in IBD and JIA. IBD patients had a lower rate of normal vaccine-associated reactions compared to JIA and HC. The encouraging role of physicians for vaccinations was the lowest in JIA patients. IBD patients had more possibilities to check antibodies before immune-suppressive therapy and had more supplementary vaccinations compared to JIA and HC. CONCLUSION JIA and IBD patients had lower vaccine coverage compared to HC. Physicians' encouragement of vaccination and the impossibility of discus about future vaccinations and their outcomes seemed the main factors for patients with immune-mediated diseases, influencing vaccine coverage. Further investigations are required to understand the reasons for incomplete vaccinations and improve vaccine coverage in both groups, especially in rheumatic disease patients. The approaches that stimulate vaccination in healthy children are not always optimal in children with immune-mediated diseases. It is necessary to provide personalized vaccine-encouraging strategies for parents of chronically ill children with the following validation of these technics.

Patients with COVID-19 most often have severe respiratory diseases, while about 19% of patients with COVID-19 exhibit gastrointestinal disorders. Excessive use of antibacterial drugs increases the risk of changes in the microbiota, the appearance of diarrhea and infection with Clostridioides difficile (CDI). Clostridium difficile infection (CDI) is a severe infectious disease of the colon caused by an obligate anaerobic organism releasing two main exotoxins: toxin A (TcdA) and toxin B (TcdB), which cause CDI symptoms: intestinal damage and inflammation of the mucous membrane, which leads to a serious complication – pseudomembranous colitis. This disease is difficult to treat and may cause a relapse. That is why emphasis is currently being put on the prevention of this disease.