Division of Bacterial Diseases, Korea Centers for Diseases Control and Prevention, Cheongju, Republic of Korea.
College of Veterinary Medicine, Chungnam National University, Daejeon, Republic of Korea.
PLoS Negl Trop Dis. 2021 Mar 2;15(3):e0009170. doi: 10.1371/journal.pntd.0009170. eCollection 2021 Mar.
In Korea, typhoid fever is a rare disease due to improved living standards. However, typhoid fever remains a major burden in developing countries and regions, such as India and Southeast Asia. In this study, we isolated Salmonella Typhi (S. Typhi) from eight patients with typhoid fever who were travelers returning from India. The strains isolated were characterized by antimicrobial susceptibility profiling and whole-genome sequencing (WGS) analysis. All strains were resistant to nalidixic acid and azithromycin. Among them, four isolates were highly resistant to ciprofloxacin (MIC ≥32 μg/ml); these strains have not been confirmed in Korea PulseNet DB. According to WGS, the ciprofloxacin-resistant strains belong to the global dominant multidrug-resistant (MDR) haplotype H58 (SNP glpA C1047T, SptP protein Q185* (premature stop codon)) and do not harbor the MDR plasmid. H58-associated SNPs in membrane and metabolism genes, including yhdA, yajI, hyaE, tryE, rlpB and metH, are present. Additionally, phylogenetic analysis assigned the H58 strains to sublineage II, whereas the non-H58 strains are closely related to haplotype H50. The presence of high-level ciprofloxacin-resistant S. Typhi haplotype H58 in Korea was first confirmed as due to influx from overseas via travelers. This study provides information about intercontinental drug-resistant transmission between countries and suggests that travelers need to be careful about personal hygiene.
在韩国，由于生活水平的提高，伤寒症是一种罕见的疾病。然而，伤寒症仍然是发展中国家和地区的主要负担，如印度和东南亚。在这项研究中，我们从 8 名从印度旅行归来的伤寒患者中分离出伤寒沙门氏菌（S. Typhi）。分离出的菌株通过抗菌药物敏感性分析和全基因组测序（WGS）分析进行了特征描述。所有菌株均对萘啶酸和阿奇霉素耐药。其中，有 4 株对环丙沙星高度耐药（MIC≥32μg/ml）；这些菌株在韩国脉冲网数据库中尚未得到确认。根据 WGS，耐环丙沙星的菌株属于全球主要的多药耐药（MDR）单倍型 H58（glpA C1047T 点突变，SptP 蛋白 Q185*（提前终止密码子）），且不携带 MDR 质粒。H58 相关的 SNP 存在于膜和代谢基因中，包括 yhdA、yajI、hyaE、tryE、rlpB 和 metH。此外，系统发育分析将 H58 菌株分配到亚系 II，而非 H58 菌株与单倍型 H50 密切相关。韩国首次确认存在高水平耐环丙沙星的伤寒沙门氏菌 H58，是由于海外旅行者的传入。本研究提供了国家间跨洲际耐药传播的信息，并表明旅行者需要注意个人卫生。
