Genetic Diversity of Campylobacter jejuni Isolates from Korea and Travel-Associated Cases from East and Southeast Asian Countries

Abstract

SUMMARY: Forty domestic and travel-associated Campylobacter jejuni isolates were analyzed by profiling 7 pathogenic genes (cdtB, cadF, Cj0131, ciaB, racR, wlaN, and virB11) along with multilocus sequence typing (MLST) and antimicrobial susceptibility testing. cdtB, cadF, and Cj0131 were present in all isolates, whereas virB11 was not detected in either domestic or travel-associated isolates. ciaB was present in all domestic isolates and 94z of travel-associated isolates. The respective detection rates of racR and wlaN in domestic and travel-associated isolates were 94z and 71z and 35.3z and 23z, respectively. MLST analyses of the 40 isolates generated 25 different sequence types (STs). ST-443 (12 isolates) and ST-21 (8 isolates) were dominant among the domestic isolates; however, STs varied among travel-associated isolates. Nalidixic acid, tetracycline, and ciprofloxacin resistance rates of the 40 isolates were 100z (40/40), 95z (38/40), and 88z (35/40), respectively. Domestic isolates exhibited 2-fold higher ciprofloxacin, telithromycin, and chloramphenicol resistance rates than travel-associated isolates. These results indicate a diverse genetic background for travel-associated C. jejuni and suggest that this pathogen may be an important emerging public health threat to travelers.

High‐Level Ciprofloxacin‐Resistant Campylobacter jejuni Isolates Circulating in Humans and Animals in Incheon, Republic of Korea

“…Genomic DNA of each isolate was used as a PCR template for the detection of six potential VAGs responsible for Campylobacter infection ( cadF , cdtB , ciaB , racR , virB11 and wlaN ) (Konkel et al., ; Bang et al., ; Cha et al., ). PCR was performed as before, except for the use of the gene‐specific primer pairs and annealing temperatures shown in Table .…”

Antimicrobial Susceptibility Patterns and Genetic Diversity of Campylobacter spp. Isolates from Patients with Diarrhea in South Korea

“…Nevertheless, from 2009 to 2013, the nalidixic acid resistance rate was 100% for human isolates and 95.2% for animal isolates, and the ciprofloxacin resistance rate was 96.8% for human isolates and 92.9% for animal isolates [ 34 ]. The fluoroquinolone resistance of C. jejuni was ciprofloxacin (89.4 to 100%) and nalidixic acid (90.9 to 100%), and there was no decreasing trend of antibiotic resistance [ 35 , 36 ]. Even our study result could not confirm a significant antibiotic resistance reduction against ciprofloxacin (83.3%) and nalidixic acid (64.9%), and maintenance of a high-level antibiotic resistance was described ( Table 2 ).…”

“…However, our results demonstrated 32.3% of tetracycline resistance in human patients ( Table 2 ). According to another domestic report, the tetracycline resistance rate between 2009 and 2013 was 74.6% for human isolates and 81.0% for animal isolates [ 35 ], and the tetracycline resistance rate among human isolates in Gyeonggi-do, Korea, in 2010 was 69% [ 46 ]. Additionally, according to a domestic report on poultry, the tetracycline resistance rate of poultry isolates in 2013 was 52% in chickens and 97% in ducks [ 38 ].…”