目的 了解深圳地区沙门菌的感染率、血清学分布和耐药性特征,为制定防控措施提供依据.方法 选择3家哨点医院(北京大学深圳医院、深圳市儿童医院、中山大学附属第八医院),对2016-2018年肠道门诊急性腹泻患者粪便标本分离的沙门菌进行血清分型、抗生素敏感性试验和耐药基因gyrA、gyrB、parC、parE的检测.结果 从2 842例腹泻患者的粪便标本中分离出187株(6.6％)沙门菌,共鉴定出25种血清型,其中鼠伤寒沙门菌的分离率最高(3.5％),其次为肠炎沙门菌(1.3％)、4,5,12:i:-(0.3％).沙门菌对氨苄西林、磺胺甲恶唑/甲氧苄啶、萘啶酸的耐药率较高,分别为81.0％、36.0％、31.0％.肠炎沙门菌和4,5,12:i:-分别对萘啶酸和氨苄西林全部耐药;鼠伤寒沙门菌和4,5,12:i:-对头孢菌素类、环丙沙星、左氧氟沙星和磺胺甲恶唑/甲氧苄啶耐药率较高.所有环丙沙星/左氧氟沙星耐药菌株的gyrA基因均发现突变,而gyrB、parC、parE基因均未发生突变.结论 鼠伤寒沙门菌和肠炎沙门菌是深圳地区流行的最常见血清型,鼠伤寒沙门菌对抗生素的耐药率较高.氟喹诺酮耐药可能与gyrA基因突变有关,建议临床合理使用抗生素,并对本地区沙门菌的流行状况进行持续监测.

BackgroundSalmonella is one of the main causative agents of diarrhea which results in substantial disease burden. To determine the prevalence, serotype distribution, and antimicrobial resistance profiles of clinical Salmonella isolates in Shenzhen, a 6-year surveillance study was conducted.ResultsA total of 297 (5.7%) Salmonella strains were isolated from stool samples from 5239 patients. Among the 42 serotypes identified, serotype Typhimurium was the most common one which represented 39.7% of the isolates (118), followed by serotype Enteritidis (71, 23.9%), London (12, 4.0%), 4, 5, 12: i: - (11, 3.7%), and Senftenberg (8, 2.7%). A high frequency of resistance was found in ampicillin (70.6%), piperacillin (64.5%), tetracycline (63.5%), and streptomycin (54.3%). Resistance to ampicillin and tetracycline was observed in 95.3% of S. Typhimurium isolates; and nalidixic acid in 93.1% of S. Enteritidis isolates. Resistance to 5 or more antimicrobial agents was found in 78.8% of S. Typhimurium and 69.0% of S. Enteritidis isolates. A decreased susceptibility to ciprofloxacin and levofloxacin was associated with amino acid alteration in gyrA gene. Point mutations without amino acid changes were seen in gyrB, parC, and parE genes.ConclusionsA broad range of serotypes are responsible for Salmonellosis in Shenzhen, with Enteritidis and Typhimurium being the most common serotypes. The high level of antibiotic resistance is of public health significance and ongoing monitoring combined with rational use of antibiotics are recommended. Point mutations in gyrA gene might play an important role in the resistance to fluoroquinolones.

Background Acute meningitis and encephalitis syndromes (AMES) is a severe neurological infection which causes high case fatality and severe sequelae in children. To determine the etiology of childhood AMES in Shenzhen, a hospital-based study was undertaken. Methods A total of 240 cerebrospinal fluid (CSF) samples from 171 children meeting the case definition were included and screened for 12 common causative organisms. The clinical data and conventional testing results were collected and analyzed. Whole genome sequencing was performed on a Neisseria meningitidis isolate. Results A pathogen was found in 85 (49.7%) cases; Group B Streptococcus (GBS) was detected in 17 cases, Escherichia coli in 15, Streptococcus pneumoniae in 14, enterovirus (EV) in 13, herpes simplex virus (HSV) in 3, N. meningitidis in 1, Haemophilus influenzae in 1, and others in 23. Notably, HSV was found after 43 days of treatment. Twelve GBS and 6 E. coli meningitis were found in neonates aged less than 1 month; 13 pneumococcal meningitis in children aged > 3 months; and 12 EV infections in children aged > 1 year old. The multilocus sequence typing of serogroup B N. meningitidis isolate was ST-3200/CC4821. High resistance rate to tetracycline (75%), penicillin (75%), and trimethoprim/sulfamethoxazole (75%) was found in 4 of S. pneumoniae isolates; clindamycin (100%) and tetracycline (100%) in 9 of GBS; and ampicillin (75%) and trimethoprim/sulfamethoxazole (67%) in 12 of E. coli . Conclusions The prevalence of N. meningitidis and JEV was very low and the cases of childhood AMES were mainly caused by other pathogens. GBS and E. coli were the main causative organisms in neonates, while S. pneumoniae and EV were mainly found in older children. HSV could be persistently found in the CSF samples despite of the treatment. A better prevention strategy for GBS, the introduction of pneumococcal vaccine, and incorporation of PCR methods were recommended.

Objective To understand the epidemiological character of diarrheagenic Escherichia coli (DEC) in Futian district of Shenzhen and thus provide the basis for prevention and control of diarrheal disease. Methods A total of 1 268 stool samples were collected from diarrhea patients by sentinel hospitals during 2015 and 2017. DEC isolates were cultured and identified by PCR method. The results were analyzed by SPSS 19.0 software package. Results Fifty DEC strains (3.9％) were isolated and two co-infections were found. The prevalence in 2015, 2016 and 2017 were 3.4％, 5.6％ and 3.8％, respectively. No significant difference was observed in the prevalence between different years (2.449, P=0.294).Enteropathogenic E.coli (EPEC) and Enterotoxigenic E.coli (ETEC) constituted 38.5％ and 36.5％ of the isolates, respectively, which was followed by Enteroaggregative E.coli (EAEC), Enteroinvasive E.coli (EIEC), and Enterotoxigenic E.coli (EHEC). The detection rates during May to October were significantly higher than those in other months (P＜0.05). The detection rates in the age group of 10～19 years, ≥60 years and ＜5 years old were 7.7％, 4.9％ and 4.2％, respectively.Conclusions EPEC and ETEC were the predominant pathotypes of DEC in Futian district. From May to October were the prevalent months of DEC and age groups of 0～5 years and over 60 years old were the main groups at high risk.

目的 了解深圳市福田区腹泻患者中腹泻病毒的流行特征以及变化趋势.方法 收集2015年-2017年哨点医院确诊腹泻患者的基本信息和粪便标本,采用反转录-聚合酶链反应(RT-PCR)方法检测诺如病毒、轮状病毒、肠道腺病毒、星状病毒,对结果进行统计分析.结果 1 972份标本中4种腹泻病毒总的检出率为21.2％ (418/1 972),其中2015年、2016年、2017年的检出率分别为23.4％、18.1％、22.8％.腹泻病毒检测阳性率依次分别为诺如病毒11.6％(228/1 972)、轮状病毒7.7％(151/1 972)、星状病毒2.1％ (41/1 972)、肠道腺病毒1.3％ (26/1 972).11月-次年1月的检出率最高,为27.3％;5岁以下儿童检出率为34.4％,显著高于其他年龄组(P＜0.05).结论 腹泻病毒在本地区长期流行,其中诺如病毒和轮状病毒是主要的病原体.5岁以下儿童是主要的感染人群,11月-次年1月是感染的高峰时间.

目的 了解深圳市某哨点医院儿童脑炎脑膜炎症候群(AMES)的细菌病原谱及其耐药特征.方法 在哨点医院收集病例的血液和脑脊液样品,用镜检、分离培养、乳胶凝集等常规方法检测病原菌,对分离的细菌进行抗生素敏感性试验.结果 在2015-2017年的120例儿童AMES病例中,从26例血液或脑脊液中检出病原菌(21.7％);依次为肺炎链球菌(9例)、大肠杆菌(5例)、表皮葡萄球菌(5例)、无乳链球菌(3例)、肺炎克雷伯杆菌(2例)、铜绿假单胞菌(1例)、金黄色葡萄球菌(1例).在测试的20株菌株中,无乳链球菌对四环素、克林霉素;肺炎克雷伯杆菌对氨苄西林;表皮葡萄球菌对青霉素、苯唑西林、阿莫西林、阿莫西林/克拉维酸全部耐药.另分离1株耐甲氧西林金黄色葡萄球菌、2株产超广谱β内酰胺酶(ESBL)大肠杆菌、1株ESBL肺炎克雷伯杆菌.结论 肺炎链球菌是该医院儿童AMES最主要的细菌病原,大肠杆菌和无乳链球菌是新生儿脑膜炎的主要病原体.应结合病原菌的耐药性特点,合理选择抗生素和加强耐药性监测.