| Title | Epidemiological relationships of Campylobacter jejuni strains isolated from humans and chickens in South Korea |
|---|---|
| Author | Jae-Young Oh1, Yong-Kuk Kwon2, Bai Wei1, Hyung-Kwan Jang1, Suk-Kyung Lim3, Cheon-Hyeon Kim4, Suk-Chan Jung5, and Min-Su Kang5* |
| Address | 1Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine, Chonbuk National University, Jeonju 54896, Republic of Korea, 2Research Planning Division, Animal and Plant Quarantine Agency, Gimcheon-si 39660, Republic of Korea, 3Bacteriology Disease Division, Animal and Plant Quarantine Agency, Gimcheon-si 39660, Republic of Korea, 4Jeollabukdo Busan Metropolitan Government Research Institute of Health and Environment, Imsil 55928, Republic of Korea, 5Avian Disease Division, Animal and Plant Quarantine Agency, Gimcheon-si 39660, Republic of Korea |
| Bibliography | Journal of Microbiology, 55(1),13-20, 2017, |
| DOI | 10.1007/s12275-017-6308-8 |
| Key Words | Campylobacter jejuni, epidemiological relationship, PFGE, MLST, clonal spread, human |
| Abstract | Thirty-nine human isolates of Campylobacter jejuni obtained from a national university hospital during 2007–2010 and 38 chicken isolates of C. jejuni were collected from poultry farms during 2009–2010 in South Korea were used in this study. Campylobacter genomic species and virulence-associated genes were identified by PCR. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were performed to compare their genetic relationships. All isolates were highly resistant to ciprofloxacin, nalidixic acid, and tetracycline. Of all isolates tested, over 94% contained seven virulence associated genes (flaA, cadF, racR, dnaJ, cdtA, cdtB, and cdtC). All isolates were classified into 39 types by PFGE clustering with 90% similarity. Some chicken isolates were incorporated into some PFGE types of human isolates. MLST analysis for the 39 human isolates and 38 chicken isolates resulted in 14 and 23 sequence types (STs), respectively, of which 10 STs were new. STs overlapped in both chicken and human isolates included ST-21, ST-48, ST-50, ST-51, and ST-354, of which ST-21 was the predominant ST in both human and chicken isolates. Through combined analysis of PFGE types and STs, three chicken isolates were clonally related to the three human isolates associated with food poisoning (VII-ST-48, XXII-ST-354, and XXVIII-ST-51). They were derived from geographically same or distinct districts. Remarkably, clonal spread of food poisoning pathogens between animals and humans was confirmed by population genetic analysis. Consequently, contamination of campylobacters with quinolone resistance and potential virulence genes in poultry production and consumption may increase the risk of infections in humans. |