Genetic Analysis of mecA Gene of Methicillin-Resistant Staphylococcus aureus from Human, Canine and Feline Origins

Abstract

The aim of the present study was to determine the genetic relatedness between Methicillin-resistant Staphylococcus aureus (MRSA) isolated from pet animals and human. In that context, 561 swabs were collected from dogs (n=238) and cats (n=323). In addition, 30 MRSA positive isolates from Qasr Elainy hospital, from different patients were also included. The collected samples were subjected for bacteriological examination for isolation of S. aureus. The recovered S. aureus isolates that were resistant to oxacillin and cefoxitin were tested for the presence of mecA, mecC, spa, and nuc genes by PCR, followed by a sequence analysis of the mecA gene in seven selected isolates. Out of 238 swab samples collected from dogs and 323 swab samples collected from cats, 13 (5.46%) and 8 (2.48%) isolates respectively were confirmed to be MRSA.  In addition, the 30 human isolates were all categorized as MRSA. The mecA gene was successfully identified in all isolates from dogs, cats and human, while spa was harbored by 13, 4 and 30 isolates from dogs, cats and human respectively. Furthermore 13, 4 and 23 isolates from dogs, cats and human were positive for the nuc gene. mecC was not identified from all examined isolates. The phylogenetic analysis of the mecA gene sequence in seven selected MRSA isolates demonstrated a high degree of similarity among isolates originating from dogs, cats, and humans. This study confirms the zoonotic spread of S. aureus and suggests that dogs and cats are probably contributing to the spread of MRSA to human.