Antimicrobial resistance and virulence of Enterococcus faecalis isolated from retail food.
Although enterococci are considered opportunistic nosocomial pathogens, their contribution to foodborne illnesses via dissemination through retail food remains undefined. In this study, prevalence and association of antimicrobial resistance and virulence factors of 80 Enterococcus faecalis isolates from retail food items were investigated. The highest rates of resistance were observed for lincomycin (73 of 80 isolates, 91%) and bacitracin (57 of 80 isolates, 71%), and lower rates of resistance (< or =40%) were found for chloramphenicol, ciprofloxacin, erythromycin, flavomycin, gentamicin, kanamycin, nitrofurantoin, penicillin, and tylosin. Overall resistance to antimicrobials was low for most isolates tested. Of the virulence factors tested, the majority of isolates were positive for ccf (78 of 80 isolates, 98%), efaAfs (77 of 80, 96%), and cpd (74 of 80, 93%). Isolates also commonly contained cob (72 of 80 isolates, 90%) and gelE (68 of 80, 85%). Very few isolates contained cylMBA (12 of 80 isolates [15%] for cylM and 9 of 80 isolates [11%] for both cylB and cylA) and efaAfm (2 of 80 isolates, 3%). Positive statistical associations (significance level of 0.05) were found between agg and tetracycline resistance, cylM and erythromycin resistance, and gelE and efaAfs and lincomycin resistance. The presence of the cylB and cylA alleles also was positively correlated with bacitracin and tetracycline resistance. Negative correlations were observed between many of the virulence attributes and resistance to ciprofloxacin, erythromycin, flavomycin, gentamicin, kanamycin, and tylosin. These data suggest that both positive and negative associations exist between antimicrobial resistance genes and virulence factors in E. faecalis isolates from foods commonly purchased from grocery stores.
McGowan-Spicer
Lori L
LL
Bacterial Epidemiology and Antimicrobial Resistance Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Russell Research Center, Athens, Georgia 30605, USA.
Fedorka-Cray
Paula J
PJ
Frye
Jonathan G
JG
Meinersmann
Richard J
RJ
Barrett
John B
JB
Jackson
Charlene R
CR
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001483:Base Sequence; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005638:Fruit / Q000382:microbiology; D006801:Humans; D008460:Meat / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D014675:Vegetables / Q000382:microbiology; D014774:Virulence / Q000235:genetics
D000900:Anti-Bacterial Agents