Molecular characterization of methicillin-resistant Staphylococcus aureus nasal isolates from Turkey

Area of Science:

• Microbiology
• Epidemiology
• Molecular Biology

Background:

• Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern, frequently colonizing the anterior nares.
• Understanding MRSA nasal carriage rates in pediatric populations is crucial for infection control.

Purpose of the Study:

• To determine the prevalence of Staphylococcus aureus and MRSA nasal carriage in Turkish elementary school children.
• To perform molecular characterization of identified MRSA strains.

Main Methods:

• Nasal swabs collected from 4,050 children in Ankara.
• Antimicrobial susceptibility testing using disk diffusion (oxacillin, cefoxitin).
• Molecular typing including PFGE, MLST, SCCmec typing, and PVL gene detection.

Main Results:

• Staphylococcus aureus colonization rate was 24.7% (1,001/4,050 children).
• MRSA carriage rate was 0.07% (3/4,050 children).
• All MRSA isolates were SCCmec type IV, negative for PVL, with two belonging to ST30.

Conclusions:

• The S. aureus nasal carriage rate is consistent with previous findings.
• The MRSA carriage rate in this cohort is notably low.
• The ST30-type IV MRSA clone, without the PVL gene, may pose a future risk for community spread in Turkey.