Determination of antimicrobial susceptibility and biofilm production in Staphylococcus aureus isolated from white coats of health university students

Abstract

This study aimed at detecting Staphylococcus aureus from white coats of college students and characterizing antimicrobial susceptibility and biofilm production. Bacterial samples (n = 300) were obtained from white coats of 100 college students from August 2015 to March 2017 S. aureus was isolated and it´s resistance profile was assessed by antimicrobial disk-diffusion technique, screening for methicillin-resistant Staphylococcus aureus (MRSA), detection of mecA gene by PCR, and determination of staphylococcal cassette chromosome mec (SCCmec) by multiplex PCR. Congo red agar (CRA) and icaA and icaD genes by PCR were used for biofilm characterization. S. aureus was identified in 45.0% of samples. Resistance of S. aureus sample to antimicrobial was seen for penicillin (72.59%), erythromycin (51.85%), cefoxitin (20.74%), oxacillin (17.04%), clindamycin (14.81%) and levofloxacin (5.18%). MRSA was detected in 53.3% of the samples with SCCmec I (52.8%), SCCmec III (25%) and SCCmec IV (11.1%). Biofilm production was observed in 94.0% S. aureus samples. These data show that biosafety measures need to be enhanced in order to prevent dissemination of multiresistant and highly adhesive bacteria across other university settings, relatives, and close persons.