Characterization of Staphylococcus aureus isolates from retail chicken carcasses and pet workers in Northwest Arkansas.
Staphylococcus aureus can be carried on the skin and nasal passages of humans and animals as a commensal. A case of human methicillin-resistant S. aureus infection resulting from contact with pork has been reported. Poultry carcasses are sold at retail with the skin intact,  but pork and beef typically are not. Thus, the risk of methicillin-resistant S. aureus human infection from whole raw poultry carcasses may be greater than that of exposure from pork or beef. The objective of this study was to isolate and characterize S. aureus from whole retail  poultry carcasses and compare the isolates to S. aureus isolates from humans. A total of 25 S. aureus isolates were collected from 222 whole poultry carcasses. The isolates were characterized phenotypically with antibiotic resistance disc diffusion assays and genotypically using  multilocus sequence typing. A total of 17 S. aureus isolates obtained from healthy humans were included and characterized in the same way as the poultry isolates. Staphylococcus spp. were recovered from all poultry carcasses. Only 25 poultry carcasses (11.2%) were contaminated  with S. aureus. Of these 25 isolates, 36% were resistant to at least one of the antibiotics tested and 20% were resistant to two or more antibiotics tested. However, 100% of the human isolates were resistant to at least one of the antibiotics and 94% were resistant to two or more antibiotics.  The results of the multilocus sequence typing indicate that most of the isolates grouped according to source. These results indicate a low prevalence of S. aureus present in poultry, and the isolates were not phenotypically similar to human isolates. The low number of S. aureus  isolates from this study indicates that chicken carcasses would appear to not be a significant source of this bacterium.
Center for Food Safety, University of Arkansas, Fayetteville, Arkansas 72704, USA. ihanning@utk.edu
Irene
I
Hanning
David
D
Gilmore
Sean
S
Pendleton
Scott
S
Fleck
Ashley
A
Clement
Si Hong
SH
Park
Erin
E
Scott
Steven C
SC
Ricke
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001131:Arkansas; D002645:Chickens / Q000382:microbiology*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005838:Genotype; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification; D012867:Skin / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification*
D000900:Anti-Bacterial Agents