Incidence and Determinants of Symptomatic and Asymptomatic SARS-CoV-2 Breakthrough Infections After Booster Dose in a Large European Multicentric Cohort of Health Workers-ORCHESTRA Project.

BACKGROUND: SARS-CoV-2 breakthrough infections (BI) after vaccine booster dose are a relevant public health issue. METHODS: Multicentric longitudinal cohort study within the ORCHESTRA project, involving 63,516 health workers (HW) from 14 European settings. The study investigated the cumulative incidence of SARS-CoV-2 BI after booster dose and its correlation with age, sex, job title, previous infection, and time since third dose. RESULTS: 13,093 (20.6%) BI were observed. The cumulative incidence of BI was higher in women and in HW aged < 50 years, but nearly halved after 60 years. Nurses experienced the highest BI incidence, and administrative staff experienced the lowest. The BI incidence was higher in immunosuppressed HW (28.6%) vs others (24.9%). When controlling for gender, age, job title and infection before booster, heterologous vaccination reduced BI incidence with respect to the BNT162b2 mRNA vaccine [Odds Ratio (OR) 0.69, 95% CI 0.63-0.76]. Previous infection protected against asymptomatic infection [Relative Risk Ratio (RRR) of recent infection vs no infection 0.53, 95% CI 0.23-1.20] and even more against symptomatic infections [RRR 0.11, 95% CI 0.05-0.25]. Symptomatic infections increased from 70.5% in HW receiving the booster dose since < 64 days to 86.2% when time elapsed was > 130 days. CONCLUSIONS: The risk of BI after booster is significantly reduced by previous infection, heterologous vaccination, and older ages. Immunosuppression is relevant for increased BI incidence. Time elapsed from booster affects BI severity, confirming the public health usefulness of booster. Further research should focus on BI trend after 4th dose and its relationship with time variables across the epidemics.

Colonisation of Staphylococcus aureus in patients with Nasal Polyposis.

BACKGROUND: Nasal polyps (NPs) are one of the most common inflammatory mass lesions of the nose, affecting up to 0.5-4% of the population. The pathogenesis of NPs has been studied widely, but it is not clearly understood. A possible role of S. aureus in nasal polyposis has been suggested by numerous studies. This study aimed to map S.aureus colonisation in NP patients in the nose in comparison to healthy controls. MATERIAL AND METHODS: We identified Staphylococcus aureus in nasal mucosal swab, collected from 58 patients with nasal polyposis from the out-patient ENT clinic of the Faculty Hospital in Nitra. We compared them to 50 patients without symptoms of nasal obstruction or NP. Isolated bacterial strains were then further identified. RESULTS: In nasal mucosa membrane, results were not statistically significant. The selected population consisted of 108 patients, of which 58 (54%) had nasal polyps and 50 (46%) didnt. We collected the following information about patients from both groups: age, gender, smoker, presence of asthma, allergy and presence of Staphylococcus aureus by cultivation from nasal mucosa. In addition, for patients with nasal polyposis we have following variables, such as: presence inflammatory diseases, allergy to acylpyrine, cystic fibrosis. Out of 58 patients with nasal polyposis 15% (n=9) were found to have S.aureus in nasal mucosa membrane, compared to the healthy controls where 6% (n=3) of patients had S. aureus. CONCLUSION: Our results did not show that S. aureus found in nasal mucosa membrane is significantly different in patients with or without NP. However, association of the presence of S. aureus in patients with nasal polyposis with asthma, allergy and inflammation has been shown.

Etiology, Risk Factors and Outcome of 1003 Cases of Infective Endocarditis from a 33-year National Survey in the Slovak Republic: An increasing proportion of elderly patients.

BACKGROUND: Infective endocarditis (IE) is still a significant cause of mortality in European hospitals, despite of the fact, that large nationwide studies were performed in last twenty years and pathogens are well known. The aim of the study was to assess risk factors, mortality, etiology and proportion of elderly patients within a longitudinal nation wide survey of infectious endocarditis in Slovakia. PATIENTS AND METHODS: Etiology, risk factors and outcome of 1003 cases of infective endocarditis (IE) in Slovakia over the last 33 years have been assessed. RESULTS: The majority of IE were caused by Staphylococci (28.3%), 15.6% were due to Viridans streptococci, 10% due to Enterococci, 8.2% by gram-negative bacteria, Acinetobacter baumannii and Pseudomonas aeruginosa, 3.7% by other organisms and 31.0% of all cases were culture negative. The following risk factors were recorded: age > 65 (36.8%), rheumatic fever (15.3%), dental surgery (8.7%), previous non-cardiological surgery (8.2 %), neoplasia (8.1%), diabetes (7.8%), any endoscopy (8.5%) and dialysis (4.6%). All patients were treated with antimicrobials, 507 (51%) also with surgery. Survival rate at day 60 after diagnosis was 88.1% (n=883). Only age >65 (34.3% vs. 49.5%, p=0.045) and persistent bacteremia (with three or more positive blood cultures 15.7% vs. 34.5%, p=0,001) were significantly associated with higher attributable mortality. Concerning risk factors, etiology and therapeutic strategies, rheumatic fever and neoplasia showed decrease in tendency. Dental surgery and tonsillitis were less frequent as well (26.7% vs. 2%, p<0,001 and 16% vs. 1%, p<0.001). There was a significant shift in etiology after 1997: culture-negative endocarditis was surprisingly more frequently observed in the 2007-2017 period than before and represented 10.7% of all cases in 1984-1990 in comparison to 25.1-25.6% in 2007-2010 and 2011-2017. Staphylococci decreased from 48% to 29.6% (2007-2017), but are still major pathogens. Persistent bacteremia (3 or more positive blood cultures 5.3% vs. 24.7%, p<0,001) was less commonly observed within the 1st period (1984-1990) in comparison to 2007-2010. More patients in the 1st period (1984-1990) had embolization complications of IE than in the fifth and sixth period (2007-2017) (76 vs. 16.3% p<0.001). CNS embolization decreased from 14% to less than 5% (p<0.003). Attributable mortality was lower too (26.7% vs. 9.5%, p<0.001) because of increased proportion of cardiac surgery in the treatment of IE in 2007-2017 in comparison to 1984-1990. CONCLUSIONS: Study has showed significant shifts in etiology, risk factors and complications over the observed time periods in Slovakia.

Bacteremias caused by Escherichia coli in cancer patients - analysis of 65 episodes.

OBJECTIVES: The aims of this study were to evaluate risk factors, clinical presentation, outcome and antimicrobial susceptibility in patients with Escherichia coli bacteremia occurring over seven years in a single cancer hospital. METHODS: Sixty five episodes of bacteremia from E. coli appearing over seven years from 12,301 admissions in a single cancer institution were retrospectively analyzed. RESULTS: The proportion of bacteremia caused by E. coli among Gram-negative bacteremia was 20.8% (the second most common organism after Pseudomonas aeruginosa), and infection-associated mortality was 17%. The incidence in 1989-1995 varied from 14.3 to 24.7%. The most common risk factors were: solid tumors as the underlying disease (70.7%); central venous catheter insertion (32.3%); prior surgery (46.2%), and prior chemotherapy within 48 h (44.4%). Neutropenia and urinary catheters did not place patients at high risk in any of the subgroups. When we compared the two subgroups of 61 cases of bacteremia - monomicrobial and polymicrobial (when E. coli was isolated from blood culture with another microorganism) - we found that acute leukemia and breakthrough (recurrence while receiving antibiotics) bacteremia were more frequently associated with polymicrobial E. coli bacteremia. There was also a difference in infection-associated mortality: monomicrobial bacteremia due to E. coli only had a significantly lower mortality in comparison with polymicrobial E. coli bacteremia (8.9 vs 35.0%, respectively; P<0.03). CONCLUSION: The susceptibility of 115 E. coli strains isolated from 65 episodes of bacteremia was stable. Only two episodes caused by quinolone-resistant strains occurred, both in 1995, after six years of using ofloxacin for prophylaxis in neutropenic patients in our hospital. We found that 85.2-91.3% of all strains were susceptible to aminoglycosides, 97.8% to quinolones, and 90-100% to third generation cephalosporins and imipenems. The patients most commonly infected had solid tumors and the mortality was only 17%.