Comparative Analysis of Aerotolerance, Antibiotic Resistance, and Virulence Gene Prevalence in Campylobacter jejuni Isolates from Retail Raw Chicken and Duck Meat in South Korea

Human infections with Campylobacter are primarily associated with the consumption of contaminated poultry meat. In this study, we isolated Campylobacter jejuni from retail raw chicken and duck meat in Korea and compared their aerotolerance, antibiotic resistance, and virulence gene prevalence. Whereas C. jejuni isolates from chicken dominantly belonged to multilocus sequence typing (MLST) clonal complex (CC)-21, CC-45 is the common MLST sequence type in duck meat isolates. C. jejuni strains from both chicken and duck meat were highly tolerant to aerobic stress. The prevalence of virulence genes was higher in C. jejuni strains from chicken than those from duck meat. However, antibiotic resistance was higher in duck meat isolates than chicken isolates. Based on the prevalence of virulence genes and antibiotic resistance, fluoroquinolone-resistant C. jejuni strains harboring all tested virulence genes except virB11 were predominant on retail poultry. Fluoroquinolone-resistant C. jejuni strains carrying most virulence genes were more frequently isolated in summer than in winter. The comparative profiling analysis in this study successfully demonstrated that antibiotic-resistant and pathogenic strains of C. jejuni are highly prevalent on retail poultry and that retail duck meat is an important vehicle potentially transmitting C. jejuni to humans in Korea.