Characterization of Staphylococcus aureus Isolated from Camel and Human samples from Aswan Governorate in Egypt

Abstract

Aim: The objective of this study was to assess the occurrence and molecular characteristics of Staphylococcus aureus isolates among camel and human samples in Aswan. Materials and Methods: A total of 320 samples: milk, nasal swabs and bus swabs were collected from camels (n= 290) and their human contacts (n= 30) from Aswan governorate. Disc diffusion test was applied to detect resistant and Methicillin-resistant Staphylococcus aureus MRSA isolates. PCR was applied for detection of the virulence genes: nuc, hla, pvl, mecA, vanA, vanB and enterotoxins (sea, seb sec and sed) genes. Results: 112 Out of 165 she camel milk samples (67.9%), 59 out of 125 camel nasal samples (47.2%), 3 out of 5 worker nasal swabs (60%) and 16 out of 25 abscesses' swabs from human infected wound (64%) were positive for staphylococci. Only 34 out of 190 staphylococci were S. aureus (17.9%) and they were tested by PCR of the nuc gene. All S. aureus isolates were sensitive to vancomycin. The two human isolates were resistant to streptomycin and erythromycin. Among 25 % of S. aureus isolated from camel milk samples were resistant to gentamicin and ceftriaxone (each), 50% and 31.2 % were resistant or intermediate resistant to streptomycin and clindamycin respectively. Among S. aureus isolated from camel nasal swabs, 18.8% were resistant or intermediate resistant to cefoxitin and ceftriaxone (each). 13 out of 34 S. aureus isolates (38.2%) were MRSA. All S. aureus isolates were amplified 279 bp of nuc gene specific for S. aureus strains. While 28, 12 and 11 isolates were harboring hla, mecA and pvl genes respectively. All S. aureus isolates were negative for vanA, vanB and enterotoxins (sea, seb sec and sed) genes. Conclusion: S. aureus and MRSA isolated from camel milk considered a potential health risk for food poisoning.