The continued and increasing development of antimicrobial resistant bacteria among the
foodborne pathogens had caused worldwide to be alarmed. Being the earliest to develop
antimicrobial resistance, Staphylococcus aureus is constantly monitored for any new
resistance development. The resistance development is often linked to wastewater and the
treatment plants where the pressure of antibiotic is the highest. Hence, this study
investigated on the prevalence of high antimicrobial resistant S. aureus in the wastewater
eluted from a poultry slaughterhouse. A total of thirty wastewater samples were collected
from a poultry slaughterhouse in Semenyih, Selangor. Most probable number (MPN)-
plating method was employed to enumerate the S. aureus count in the wastewater. The
results indicated that S. aureus was highly present whereby all samples (100%) were
positive and the concentration ranged between 11 – 2.1 x 104 MPN/ml. Isolated S. aureus
strains were screened for their antimicrobial susceptibility using the Kirby-Bauer Disk
Diffusion Test method to classify their antimicrobial resistance eleven antibiotics. The
MAR index measured was between 0.18 and 0.91, inferring that the strains are highly
antimicrobial resistance. All S. aureus strains were 100% resistant to ampicillin (25 µg)
and cefazolin (30 µg). 94.1% of the strains were resistant to penicillin (10 µg) which
phenotypically indicated these strains are Methicillin-resistant S. aureus (MRSA).
Notably, 17.6% of the strains developed resistance to vancomycin and was categorized as
Vancomycin-resistant S. aureus (VRSA). There is a need to take drastic preventive
measures to control the resistance development in S. aureus to conserve public health.