University students, particularly those in the healthcare disciplines, constitute a category of particular interest in regard to COVID-19 vaccines and the attitudes to vaccination, as their future professional role will enable them to inform and educate citizens regarding vaccination. The objectives of the study were to investigate the vaccination coverage with a COVID-19 vaccine among students from different degree programs at the Medical universities in Bulgaria behaviors and attitudes toward vaccination with a COVID-19 vaccine. A prospective cross-sectional study in the period September 2021- March 2022 was conducted. Information on demographics, university program, year of study, general attitudes and behavior towards vaccines and attitudes and personal experience with COVID-19 and COVID-19 vaccines were collected. The chi-square test was used to test for associations and binominal logistic regression was used to identify possible predictors for vaccination. A total of 3050 students with a median age of 22 years, predominantly female took part in the study. Three-thirds of the students (73.5%) have been vaccinated against COVID-19. The main reasons for vaccine hesitancy in both group of students were the fear of side effects and the doubts about the safety of the vaccines although non-vaccinated students significantly more frequently express those fears. Respondents who considered to have: a) limited access to sufficient information to inform COVID-19 vaccine uptake; b) lack of public awareness and education campaigns about effectiveness and safety of COVID-19 vaccines; c) insufficient information about COVID-19 vaccines during the University education; and d) had a positive COVID-19 diagnosis were less likely to be vaccinated. Students who have not completed the mandatory immunization cycle according to country schedule were also less likely to have completed COVID-19 vaccination. The students showed an overall positive attitude towards the COVID-19 vaccines. Promoting informational campaigns that emphasize the vaccine's safety will be more effective to further increase the vaccination coverage with COVID-19 vaccines.

Background: Infective endocarditis (IE) continues to be a disease with high mortality despite medical advances. Objective: To investigate the characteristics and prognosis of IE according to the affected valves. Material and methods: The study is retrospective, single-center, cross-sectional and includes 270 patients with diagnosis IE, for the period 2005 – 2021, who received treatment at the University Hospital "St. Georgi" in Plovdiv, Bulgaria. Results: Single-valve IE (SIE) was found in 82.6% (n-222), multivalvular IE (MIE) in 16.66% (n=45) and device IE (CDRIE) in 0.74% (n=2) patients. The most commonly affected valve was the aortic 44.8% (n=121). The predominant multivalvular involvement was aortic-mitral valves (AV-MV) – 13.7% (n=37). The patients with tricuspid valve (TV) IE were significantly younger – 39 (30) years and were more frequently male (80.8%). Mortality was higher in MIE than SIE (31.1% vs 23.8%) and highest in multivalve aortic-tricuspid (AV-TV) IE (75%). Early surgery was done most in AV-MV IE 29.7% (n=11). Charlson comorbidity index was significantly higher in MV 4 (4) and AV 3 (3) than TV IE 1 (5) (p=0.048 and p=0.011, respectively). Septic shock occurred most frequently in AV-TV involvement (75%; p=0.0001). The most common causative agent was Staphylococcus group. Staphylococcus aureus affected more often TV alone 46.2% (n=124) vs. AV 9.9% (n=14); p=0.0001 and vs. MV 22.6% (n=17), p=0.022; Staphylococcus coagulase-negative (CNG) was the prevalent cause of MV IE 22.7% (n=17) vs AV-MV 2.7% (n=1); p=0.007. Streptococci were represented in a low percentage and only in left-sided IE, and more frequently in AV-MV 18.9% (n=7); vs. AV 6.6% (n=8); (p=0.025). Conclusion: Aortic valve is the most frequently affected valve, as single valve IE or multivalve AV-MV, with the predominant causative agents Staphylococcus group. The AV-TV IE has the worst prognosis, with the most common complication of septic shock and the highest in-hospital mortality.