2009-2013年全国伤寒/副伤寒流行特征及分子分型分析

摘要

目的 分析2009-2013年全国伤寒/副伤寒流行特征及分子分型特征,为伤寒/副伤寒的防控、监测策略制定及调整提供参考依据.方法 分析2009-2013年全国伤寒/副伤寒发病的流行特征及突发公共卫生事件情况.针对13个国家级监测点的伤寒/副伤寒病例,采用病原分离培养、血清学检测、药物敏感性试验、PFGE等方法进行病原学特征分析.结果 2009-2013年全国伤寒/副伤寒年均发病率为1.03/10万,报告发病数及报告发病率逐年下降.报告病例数较多的省份为云南省、贵州省、广西壮族自治区、湖南省、浙江省、广东省及新疆维吾尔自治区.0～4岁组为发病率最高.农民、散居儿童发病构成比自2009年逐年上升.7-8月及夏秋季为发病高峰.2009-2013年共报告25起伤寒/副伤寒暴发疫情.13个监测点的伤寒/副伤寒病例标本分离培养的阳性率为3.00％(940/31 322),其中,甲型副伤寒沙门菌占68.19％(641/940),伤寒沙门菌占31.60％(297/940).伤寒沙门菌和甲型副伤寒沙门菌均对萘啶酸的耐药率最高,分别为50.22％和85.33％.伤寒沙门菌PFGE带型多而分散,甲型副伤寒沙门菌带型相对少而集中.结论 虽然我国伤寒/伤寒发病处于低发水平,但时有暴发,应进一步加强以实验室为基础的伤寒及副伤寒病原确诊、暴发发现及应对能力,建立耐药监测系统,在新的高发省份加强监测并开展危险因素调查.%Objective To understand the epidemiological and molecular characteristics of typhoid and paratyphoid in China from 2009 to 2013,and provide evidence for the prevention and control of typhoid and paratyphoid,the development and improvement of surveillance strategies.Methods Epidemiological analysis was conducted on the incidence data of typhoid and paratyphoid,and related public health emergencies in China during 2009-2013.Pathogen isolation and culture,serologic test were conducted for the typhoid and paratyphoid cases from 13 national surveillance sites.The isolates were subjected to antimicrobial susceptibility testing.Pulsed-field gel electrophoresis (PFGE) was performed for the molecular typing of these isolates.Results The average incidence of typhoid and paratyphoid in China during this period was 1.03/100 000.The reported case number and incidence decreased with year.The provinces reporting high case numbers were Yunnan,Guizhou,Guangxi,Hunan,Zhejiang,Guangdong and Xinjiang.The incidence of age group 0-4 years was highest.The proportion of farmers and children outside child care settings showed an increasing tendency over time.The annual incidence peak was during July-August.Twenty five outbreaks occurred during 2009-2013.The results of pathogen isolation and culture showed that the positive rate was 3.00％ (940/31 322),among the positive isolates,the proportion of Salmonella paratyphi A accounted for higher proportion (68.19％,641/940) compared with Salmonella typhi (31.60％,297/940).The drug resistances of Salmonella typhi and Salmonella paratyphi varied,but their resistances to nalidixic acid were highest (50.22％ and 85.33％) respectively.A certain amount of Salmonella typhi isolates showed the resistance to the 3rd generation cephalosporins.PFGE analysis showed divergent patterns of Salmonella typhi compared with limited patterns of Salmonella paratyphi A.Conclusion The epidemic level of typhoid and paratyphoid in China was relatively low,but the outbreak occurred occasionally.It is necessary to enhance the laboratory-based surveillance,particularly the capability of etiological diagnosis,outbreak investigation,response and antibiotic resistance monitoring,and conduct risk factor investigation in provinces with high incidences in recent years.