Species shift and multidrug resistance of Campylobacter from chicken and swine, China, 2008-14

The objective of this study was to investigate the prevalence and antimicrobial resistance of Campylobacter isolated from broiler chickens and swine during 2008-14. Campylobacter isolates were collected from samples of intestinal content and excreta from broiler chickens and swine from slaughter houses as well as conventional farms in five Chinese provinces during 2008-14. The agar dilution method was used to determine the susceptibility of Campylobacter isolates to seven antimicrobial agents. The chi(2) test and Fisher's exact test were used to perform the statistical analysis. In total, 989 Campylobacter jejuni and 1991 Campylobacter coli were isolated from 10aEuroS535 samples. MIC results revealed a high prevalence of multidrug resistance among these Campylobacter isolates. In addition, we observed an apparent shift of the dominant species from C. jejuni to C. coli in chickens and this species shift coincided with an increased prevalence of macrolide-resistant C. coli. It is worth noting that almost 100% of the C. jejuni and C. coli isolates were resistant to fluoroquinolones. The high prevalence of fluoroquinolone and macrolide resistance in Campylobacter suggests that these two clinically important antibiotic classes may no longer be suitable for the treatment of human campylobacteriosis in China. Thus, enhanced surveillance and control efforts are needed to reduce antimicrobial resistance in this group of major foodborne pathogens.