Persistence of Antibacterial Resistance and
Virulence Gene Profile of methicillin resistant Staphylococcus aureus (MRSA) Isolated From Humans and Animals
Bitrus, Asinamai Athliamai1, Zunita
Zakaria1,*, Siti Khairani Bejo1 and Sarah
Othman2
1Faculty
of Veterinary Medicine; 2Faculty of Biotechnology and
Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang,
Malaysia *Corresponding author: zunita@upm.edu.my
Abstract
The persistence of antibacterial resistance and
virulence gene profile of well characterized MRSA isolated from animals and
human was determined using antibiotic susceptibility testing and PCR
amplification of virulence and methicillin resistance gene. Antibiotic
susceptibility testing revealed a general reduction in the rate of resistance to
antibiotics previously tested.Isolates
were currently susceptible to minocycline a tetracycline derivative, amikacin
and gentamicin respectively. Resistance to cefoxitin and oxacillin were
currently observed in 64 and 79% of all the isolates which in the case of
cefoxitin it was less than the 86% while a bit higher in oxacillin as reported
in the previous study. In addition, currently 57%, 43% and 36% of the isolates
were resistant to amoxicillin, tetracycline and erythromycin which is less than
the isolates previous resistance profile to amoxicillin and erythromycin whereas
unchanged in the case of tetracycline.
Four (29%) of the isolates were also currently resistant to vancomycin,
doxycycline and amoxicillin-clauvulanic acid; while only two isolates were
resistant to vancomycin and three isolates were resistant to doxycycline in the
previous study.No changes were observed
in the number of isolates resistant to amoxicillin-clauvulanic acid.Resistance to more than one class of antibiotics was observed in 64% of
the isolates. Currently we observe loss of methicillin resistance determinants
mecA and susceptibility to all
antibiotics tested in three isolates and reduced susceptibility in two isolates.