Introduction: Staphylococcus aureus is one of the most common causes of nosocomial infections. The main sources of transmission are hospital staff and contaminated hands.
Aim: The current study presents data on nasal colonization among medical students undergoing training in high-risk hospital departments.
Materials and Methods: We analyzed 253 nasal and 241 throat secretion samples from medical students who opted to be examined in the Laboratory of Microbiology at St. Marina University Hospital in Varna during the period 2021–2023. The samples were cultured on blood agar, and Staphylococcus aureus was identified using standard biochemical tests. Statistical analysis was performed using R Project software (version 4.0.4/2021-02-15).
Results: Only 15.8% of nasal secretion samples tested positive for Staphylococcus aureus. Positive throat samples were almost negligible, accounting for only 1.2%. The proportion of positive women was higher, but the difference was not statistically significant (17.3% vs. 14% of men; χ² = 0.5 and p-value = 0.5). No statistically significant difference was observed in the number of positive samples across different age groups.
Conclusion: Despite the low carriage rate observed, screening for nasal colonization can help reduce the risk of nosocomial transmission.
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