广州市夏季一起隐性感染厨工引起诺如病毒感染性腹泻暴发调查

Investigation of the Norovirus diarrhea outbreak cause by the recessive infection kitchen staff in Guangzhou in the summer

目的调查广州市某公司诺如病毒感染性腹泻暴发的感染来源、传播途径和危险因素,为制定防控策略提供科学依据。方法运用现场流行病学调查方法进行调查分析,采用荧光RT-PCR方法检测诺如病毒核酸,并对诺如病毒进行基因序列扩增和测定分析同源性。结果 2016年6月2~17日,广州市某公司共发现诺如病毒感染性腹泻病例34例,罹患率为15.25%(34/223)。所有病例症状均为轻症,临床表现以呕吐(64.71%)、腹泻(47.06%)为主,病程为2~144 h,中位数为45 h。发病高峰主要在6月7~8日(97.06%,33/34)。公司不同部门发病差异无统计学意义(两两比较P>0.05)。病例对照研究结果提示:6月6、7日中餐是危险因素(OR=3.045,95%CI:1.04~8.90;OR=11.63,95%CI:2.98~45.45)。采集30份样本(病例肛拭子25份、厨工肛拭子2份、环境拭子3份)进行检测,均未检出常规食物中毒致病菌,22份(病例肛拭子19份、厨工肛拭子2份、环境拭子1份)检出GⅡ-4型诺如病毒。厨工感染的诺如病毒与病人的基因序列高度同源,隐性感染厨工工作时未戴手套、口罩。通过停止供餐、隔离病人、加强消毒等综合措施后疫情终止。结论广州市某公司暴发的疫情为一起隐性感染厨工引起的食源性诺如病毒感染性腹泻暴发。建议完善诺如病毒疾病监测与监督体系。

Objective Investigation of the Norovirus diarrhea outbreak in a company of Guangzhou,to identify the source of infection,route of transmission and risk factors, the scientific basis for the corresponding prevention and control strategies. Methods Investigated by utilizing the method of Field Epidemiology. Using Fluorescence rt-pcr to measuring Norovirus nucleic acid detection,gene sequence amplification and the determination of homology analysis. Results There were 34 cases of Norovirus diarrhea of a company in Guangzhou,attack rate is 15. 25%. All cases symptoms are mild,the main clinical manifestation are vomiting（ 64. 71%） and diarrhea（ 47. 06%）,course of disease is 2 ～ 144 hours,median is 45 hours. Peaks are mainly concentrated in June 7 ～ 8（ 97. 06%,33/34）,the onset of different divisions of the company there was no significant difference（ comparing with each other P〉0. 05）. A case-control study tip： the lunch of June 6 ～ 7 th is risk factors（ OR = 3. 045,95% CI： 1. 04 ～ 8. 90; OR = 11. 63,95% CI： 2. 98 ～ 45. 45）. Collect 30 samples（ 25 case anal swabs,2 kitchen staff anal swabs,3 environmental swabs）,did not check out the regular food poisoning pathogenic bacteria,22 cases（ 19 case anal swabs,2 kitchen staff anal swabs,1 environmental swab） detect out GⅡ-4 Norovirus. kitchen staff infected norovirus and the patient＇s highly homologous gene sequences,the recessive infection kitchen staff did not wear gloves while working. After stopping feeding,isolating the patient,strengthening disinfect and other comprehensive measures,the epidemic stopped. Conclusion The outbreak is the the Norovirus diarrhea outbreak cause by the recessive infection Kitchen staff. The monitoring of Norovirus infection in kitchen workers should be strengthened,implement relevant health supervision.