Introduction: Seasonal variation has been observed for bacterial and viral infections (e.g., COVID-19 [1]), but also for numerous cardiac problems. However, little information is available on the seasonality of infectious endocarditis (IE), a rare disease that is usually linked to a bacterial origin. Data from the Polish population are lacking.
Materials and Methods: Our retrospective study focused on the identification of patients with IE, who were hospitalized at the University Hospital in Krakow between 2005–2022. For this purpose, we searched the medical records system using the ICD-10 code. We decided to divide our patients into four groups (winter, spring, summer, autumn), based on the date of admission to the hospital. Comparison of the distribution of IE incidents by season was performed with the ch2 test.
Results: One hundred and ten patients were included in the study (median age 62.5 years (range 20–94), 72 men (65.45%)). The left native valve IE was diagnosed in 49% of the patients, the prosthetic valve IE in 16%, the right valve IE in 27% and the implantable cardiac electronic devices IE in 12% of the subjects. The outcomes comprised of cardiac surgery (n = 53), embolism (n = 16), death (n = 15) and metastatic infections (n = 5). No differences in the incidence of IE by season were observed.
Conclusions: In the preliminary observation of IE cases of patients admitted to the University Hospital in Krakow, Poland no seasonal pattern of IE was detected. Therefore, IE should be taken into account in the differential diagnosis at any time of the year.

Staphylococcus aureus (S. aureus) has been recognized as one of the important zoonotic pathogens. However, it was limited about the epidemiology and genetic characteristics of S. aureus isolated from pigs in Hunan province, china. The aim of this study was to determine the characteristics of 163 S. aureus isolated from 590 pigs in Hunan Province, China. All isolates were characterized by agr typing, detection of virulence genes and antibiotic resistance genes, lethal test of mice and antibiotic susceptibility tests. The results showed that 30 strains of the 163 isolates were divided into agrI (18.40%), agrII (36/163, 22.09%), agrIII (20/163, 12.27%,), agrIV (20/163,12.27%) and the remaining 57 isolates were amplified negative by agr primers. In the 163 isolates, the detection rate of the virulence genes hlb, hld, hla, icaA, seb, fnbA, eta, etb, sea, tst and pvl ranged from 2.45% to 100%. The 43 isolates that were lethal to the mice, had β-hemolytic activity, the number of virulence genes of which was 7.8% higher than that of the remaining 120 non-fatal strains. The resistance rates of the 163 isolates to the 15 antibiotics were 0% (0/163) - 100% (163/163). All isolates were susceptible to Vancomycin and only 7 isolates were methicillin - resistant S. aureus (MRSA). The detection rates of the 11 resistance genes was 0% (0/163) - 100% (163/163). This study first to describes the epidemiology and characteristics of S. aureus from pigs in Hunan Province, which will help in tracking the evolution of epidemic strains and preventing pig-human transmission events.

The objectives of this study were to determine the genetic relatedness, antibiogram and virulence factors of Staphylococcus aureus (S. aureus) isolated from bovine mastitis, associated farm workers, dairy cow farm veterinarians (private veterinarians), veterinary students, and non-veterinary university students. A total of 84 S. aureus isolates (27 from mastitis, 11 from farm workers, 9 from private veterinarians, 22 from veterinary students, and 16 from non-veterinary university students) were used to determine antimicrobial sensitivity patterns using disk diffusion test, virulence factors using PCR technique and phylogenic analysis using pulsed field gel electrophoresis. All S. aureus isolates were resistant to 2 or more commonly used antibiotics. All isolates from mastitis, farm workers, and veterinary students carried the genes encoding coagulase and thermonuclease factors while isolates from non-veterinary university students carried the genes encoding coagulase, clumping, and thermonuclease factors. The mecA gene was detected in 22.2%, 81.8%, 100%, 95.5% and 100% of isolates from mastitis, farm workers, private veterinarians, veterinary students, and non-veterinary university students, respectively. In the phylogenic analysis, 10 (45.5%), 6 (66.7%) and 8 (72.7%) isolates from veterinary students, private veterinarians and farm workers, respectively were more than 80% similar to isolates from mastitis. Results of this study indicate that S. aureus isolates from mastitis milk and those from related dairy cow personnel and veterinarians share similar antimicrobial sensitivity patterns and virulence factors, therefore a common source of bacteria may exist. Furthermore, possible transmission of S. aureus between cows and cow-related personnel and vice versa could also exist.