Abstract

Methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistantStaphylococcus intermedius (MRSI) are both major causes of skin and wound infections in humans and domesticated animal populations respectively. In order to investigate the colonization rates in pets, nose, mouth, or skin swabs were taken from 74 healthy pets (61 dogs and 13 cats) in south Louisiana, USA.Staphylococci were isolated by routine culture, speciated based on biochemical tests and confirmed by polymerase chain reactions. Our results show a 93% (69/74) colonization rate of domesticated pets by coagulase positiveStaphylococci, with 50% (37/74) of animals harboring S. aureus, 43% (32/74) being colonized with S. intermedius and 5.4% (4/74) of pets carrying MRSI. Two of the MRSI contained Staphylococcal cassette chromosome mec type III while one isolate contained a type V genetic element. The fourth MRSI isolate did not show any of the SCCmec types I - V tested. All of the 4 mecA positive strains were isolated from dogs. Antibiotic susceptibility patterns were determined for the MRSI. Our results indicate that pets harbor pathogens that have zoonotic capability and suggest that domesticated animals have the potential to serve as vectors for the transfer of methicillin resistance.

Key words: SCCmec, Staphylococcus aureus, Staphylococcus intermedius, methicillin resistant, dogs, cats.