诺如病毒急性胃肠炎疫情中患者的感染特征分析

Infection characteristics of patients in acute gastroenteritis outbreaks caused by noroviruses

目的 分析诺如病毒急性胃肠炎疫情中患者的感染特点.方法 收集2014年4月-2016年3月北京市诺如病毒急性胃肠炎疫情中的病例资料及标本,使用Real time RT-PCR检测患者标本中诺如病毒核酸及其分型,采用描述流行病学方法分析诺如病毒急性胃肠炎的感染特征.结果 共收集1 743名诺如病毒急性胃肠炎临床诊断病例,其中12岁以下儿童占比77.68％（1 354/1 743）.688名病例中诺如病毒检出率为73.98％ （509/688）.便标本、肛拭子和呕吐物标本中诺如病毒检出率依次递减（χ2=67.798,P＜0.001）.诺如病毒临床诊断病例中,最常见的症状为呕吐（93.98％）,其次为腹痛（40.34％）、腹泻（30.35％）、发热（27.94％）.6岁以下儿童患者呕吐症状发生率最高（98.14％）,18岁以上患者腹泻症状发生率最高（68.12％）,随着患者年龄的增加,呕吐症状的发生率逐渐降低（χ2=100.913,P＜0.001）,腹泻症状的发生率逐渐升高（χ2=261.164,P＜0.001）.GⅠ和GⅡ组诺如病毒患者之间呕吐、腹泻、腹痛症状的发生率差异无统计学意义,GⅡ组患者（34.49％,149/432）比GⅠ组患者（18.18％,14/77）有更高的发热症状发生率（χ2=7.985,P＜0.01）.结论 12岁以下儿童是急性胃肠炎疫情中诺如病毒感染的主要人群;呕吐是诺如病毒急性胃肠炎的最常见症状,呕吐、腹泻发生率与患者年龄存在趋势相关;GⅡ组患者比GⅠ组患者有更高的发热症状发生率.

Objective To analyze the infection characteristics of patients in acute gastroenteritis outbreaks caused by norovimses.Methods Between April 2014 and March 2016,the clinical data and samples were collected from the patients in acute gastroenteritis outbreaks caused by noroviruses in Beijing.Noroviruses were detected and genotyped using real time RT-PCR,and the infection characteristics of norovirus gastroenteritis were analyzed using the descriptive epidemiological method.Results A total of 1743 clinical diagnosed cases of norovirus gastroenteritis were collected,and children under 12 years old accounted for 77.68% （1354/1743）.The detection rate of noroviruses was 73,98% （509/688）.The detection rates of noroviruses in fecal,swab and vomitus samples were gradually decreased （χ2 =67.798,P 〈0.001）.Among these clinical diagnosed cases,vomiting was the most common symptom （93.98%）,followed by abdominal pain （40.34%）,diarrhea （30.35%） and fever （27.94%）.The most common symptom of patients under 6 years old was vomiting（98.14%）,whereas diarrhea was most common among over 18 years old patients （68.12%）.With the increase of age of the patients,the incidence of vomiting was gradually decreased （χ2 =100.913,P 〈 0.001）,whereas the incidence of diarrhea was gradually increased （χ2 =261.164,P 〈 0.001）.There was no statistical difference in vomiting,diarrhea and abdominal pain symptoms between patients infected with genogroup Ⅰ and Ⅱ noroviruses,and patients infected with genogroup Ⅱ （34.49%,149/432） had the higher incidence rate of fever than that of genogroup Ⅰ （18.18%,14/77） （χ2 =7.985,P 〈 0.01）.Conclusions Noroviruses mainly infected children under 12 years old in acute gastroentertis outbreaks.The most common symptom of patients with acute gastroenteritis caused by noroviruses was vomiting,and the incidences of vomiting and diarrhea were significantly correlated with age of the patients.Patients infected with genogroup Ⅱ had the higher incidence rate of fever than genogroup Ⅰ infection.