我国5岁以下儿童小肠结肠炎耶尔森菌感染临床特征及病原学分析

目的 了解我国5岁以下儿童小肠结肠炎耶尔森菌腹泻病例临床与病原学特征,分析其可能的感染来源,为小肠结肠炎耶尔森菌病的防控与诊断提供科学依据。 方法 收集2010—2020年间来自全国10个省市自治区哨点医院儿童腹泻标本、调查及回访问卷;对标本进行小肠结肠炎耶尔森菌的分离鉴定;菌株进行生物分型、血清型鉴定;毒力基因检测以及脉冲场凝胶电泳(pulsed field gel electrophoresis,PFGE)分型。 结果 2010—2020年共监测11 377例,分离到致病性小肠结肠炎耶尔森菌63株,包括61株O:3血清型、2株O:9血清型菌株,5岁以下腹泻儿童感染率0.55%(63/11 377)。不同性别儿童对致病性小肠结肠炎耶尔森菌的感染率差异无统计学意义,1～5岁感染率高于≤1岁病例(χ²=44.836,P＜0.05),感染患儿中1～5岁发热比例高于≤1岁(χ²=11.508 ,P<0.05),随访病例未发现后遗症。我国儿童感染O:3血清型致病性小肠结肠炎耶尔森菌的PFGE带型存在多样性,优势带型为K6GN11C30021、K6GN11C30012。 结论 我国5岁以下儿童感染致病性小肠结肠炎耶尔森菌的生物血清型以3/O:3为主,偶有4/O:3与2/O:9。根据患儿感染特点与高发季节推测食源为主要感染来源,需进一步调查研究。

Clinical characteristics and etiological analysis of Yersinia enterocolitica infection in children under 5 years old in China

Objective To understand the clinical and etiological characteristics of Yersinia enterocolitica diarrhea in children under 5 years old in China, to analyze the possible source of infection, and to provide a scientific basis for prevention, control and diagnosis of Yersinia enterocolitica infection. Methods We collected children’s diarrhea specimens, survey and follow-up questionnaires from sentinel hospitals across 10 provinces and cities from 2010 to 2020. Yersinia enterocolitica was isolated from the specimens, and biotypes and serotypes of the strains were identified. Virulence genes detection and pulsed field gel electrophoresis(PFGE) were conducted. Results A total of 11,377 cases were monitored from 2010 to 2020, and 63 strains of pathogenic Yersinia enterocolitica were isolated, including 61 strains of O:3 serotype and 2 strains of O:9 serotype. The infection rate of diarrhea children under 5 years old was 0.55%(63/11,377). No statistically significant difference was found in the infection rate of Yersinia enterocolitica between boys and girls, but the infection rate was higher in children aged 1-5 years than in ones aged ≤1 years(χ;=44.836, P<0.05). In diarrhea children with pathogenic Yersinia enterocolitica, the fever ratio was higher in children aged 1-5 years than in ones aged ≤ 1 years(χ;=11.508, P<0.05). No complications were observed in the follow-up cases. The PFGE patterns of O:3 serotype strains in children with pathogenic Yersinia enterocolitica were diverse, and the main dominant patterns were K6 GN11 C30021 and K6 GN11 C30012. Conclusion The bio-serotype of pathogenic Yersinia enterocolitica in children under 5 years old in China are mainly 3/O: 3,but occasionally 4/O: 3 and 2/O: 9. According to the children’s infection characteristics and the peak season,it is speculated that food is the main source of infection,which needs further investigation.