基于全基因组测序的弯曲菌食物中毒事件的病原学研究  

Whole genome sequencing etiological study of a Campylobacter food poisoning event

作　　者：何娇明 马艳萍 刘楚云[1] 陈辉[1] 俞慕华[1] 鞠长燕[1] HE Jiao-ming;MA Yan-ping;LIU Chu-yun;CHEN Hui;YU Mu-hua;JU Chang-yan(Nanshan Center for Disease Control and Prevention of Shenzhen,Shenzhen 518054,China)

机构地区：[1]深圳市南山区疾病预防控制中心,深圳518054

出　　处：《中国人兽共患病学报》2023年第10期933-940,950,共9页Chinese Journal of Zoonoses

基　　金：深圳市南山区医学重点学科(传染病预防控制)。

摘　　要：目的对深圳地区一起疑似弯曲菌引起的食物中毒事件进行病原菌全基因组测序分析,了解本地区引起食物中毒的弯曲菌的病原特征。方法采集食物中毒病例肛拭子样本和可疑食品样本,用双孔增强过滤法进行弯曲菌分离,用微生物质谱系统进行鉴定,对分离到的弯曲菌用琼脂稀释法进行抗生素敏感性分析。用illumina二代测序方法进行菌株的全基因组测序,将菌株序列与Resfinder、CARD、MLST和VFDB数据库比对,分别获得耐药基因、ST型和毒力因子。用K-mer tree方法绘制系统发育树。结果共分离到17株弯曲菌,其中12株空肠弯曲菌,5株结肠弯曲菌,均来源于病人。17株菌均携带flaA、cadF、cdtA、cdtB、cdtC等毒力基因。药敏结果显示空肠弯曲菌耐药率最高的是四环素(100%),其次是萘啶酸(91.67%)、环丙沙星(83.34%)和庆大霉素(58.33%)。58.33%(7/12)的空肠弯曲菌中具有多重耐药。80%(4/5)的结肠弯曲菌对除了氯霉素类、林克酰胺类外的其它抗生素均耐药,100%的结肠弯曲菌存在多重耐药。100%的弯曲菌携带四环素类、β-内酰胺类耐药基因和gyrA基因点突变,76.47%(13/17)的弯曲菌携带氨基糖苷类耐药基因。MLST结果显示空肠弯曲菌分为6个ST型,ST-12294(6/12)、ST-12295(1/12)、ST-12296(1/12)是新发现的ST型,其中ST-12294与2021年克罗地亚地区的人源分离株、2018年深圳地区的鸡源分离株高度相关。结肠弯曲菌均为ST-828型,归属ST-828 complex,与2018年深圳蛇口市场鸡源分离株高度相关。结论本次是一起ST-12294型空肠弯曲菌和ST-828型结肠弯曲菌混合感染引起的食物中毒事件。弯曲菌多重耐药率高,需要引起重视。This study was aimed at investigating the pathogenic characteristics of Campylobacter.A suspected food poisoning event caused by Campylobacter was analyzed by whole genome sequencing of the pathogen in Shenzhen.Patient anal swab samples and suspected food samples were collected.Campylobacter were isolated with dual pore enhanced filtration and a fully automated microbial mass spectrometry system.The isolates were analyzed for antibiotic sensitivity with the agar dilution method.The whole genome of the strain was sequenced through Illumina second generation sequencing.The strain sequence was compared with the Resfinder,CARD,MLST,and VFDB databases to determine resistance genes,ST types,and virulence factors,respectively.The phylogenetic trees were obtained with the K-mer tree method.A total of 17 isolates,12 of C.jejuni,and 5 of C.coli,were isolated from patients.The 17 strains carried virulence genes such as flaA,cadF,cdtA,cdtB,and cdtC.The drug sensitivity results indicated that the highest resistance rate of C.jejuni was to tetracycline(100%),followed by naphthyric acid(91.67%),ciprofloxacin(83.34%),and gentamicin(58.33%).Multidrug resistance was found in 58.33%(7/12)of C.jejuni isolates.However,80%(4/5)of the isolates of C.coli were resistant to antibiotics other than chloramphenicols and lincomamides;100%of C.coli isolates had multiple drug resistance.Moreover,100%of the Campylobacter carried tetracycline resistance genes,β-lactam resistance genes,and point mutation of the gyrA gene;and 76.47%(13/17)carried aminoglycoside resistance genes.The MLST results indicated that C.jejuni was divided into six ST types,among which ST-12294(6/12),ST-12295(1/12),and ST-12296(1/12)were newly discovered.ST-12294 was highly correlated with human isolates from Croatia in 2021 and chicken isolates from Shenzhen in 2018.C.coli was entirely ST-828 type and highly correlated with chicken isolated strains from the Shenzhen She kou market in 2018.This food poisoning event was caused by mixed infection of C.jejuni type ST-12294 and

关 键 词：弯曲菌 全基因组测序 耐药基因 毒力基因 食物中毒 

分 类 号：R378.3[医药卫生—病原生物学]