Nasal Carriage and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus from Healthcare Workers and Community People in Minia City, Upper Egypt

Background and study aim: Human anterior nares can be colonized by Staphylococcus aureus, which represents a great risk of developing invasive infections. This study aimed to assess resistance profiles and the prevalence of resistance genes in Staph aureus strains isolated from nasal swabs of healthcare workers and community people. Patients and Methods: two hundred and thirty-three nasal specimens were collected from both healthcare workers and community people in Minia City. S. aureus was identified by conventional methods. Antibiotic sensitivity testing was done using the Kirby-Bauer Disk Diffusion assay. Screening of virulent genes including (mec A, pvl, hla, seb, fnbA, icaA and tsst-1) was done using polymerase chain reaction (PCR). Results: A total of 95 S. aureus isolates were recovered, 46 (48.4%) were isolated from healthcare workers and 49 (51.6%) from community people. Virulence genes mec A, hla, fnbA, and seb were detected in all-positive strains as follows: 14 (48.3%), 10 (34.5%), 4 (13.8%), and 2 (6.9%) respectively. Virulence genes (mec A hla, fnbA, and seb genes) were more detected among S. aureus isolates of community people than those nasally harbored by healthcare workers. The Ica A gene was only detected in healthcare workers' pvl-positive strains (8, 28%), while the tsst-1 gene wasn't detected among all S. aureus pvl-positive strains. Conclusion: Nasal carriage of S. aureus were detected in both community people and health care workers, almost equally. Virulence genes (mec A, pvl, hla, fnbA, and seb genes) were more detected in strains isolated from community people than those isolated from healthcare workers.