2017-2021年北京市丰台区诺如病毒腹泻的流行病学特征分析

Epidemiological Characteristics of Norovirus Diarrhea During 2017 – 2021 in Fengtai District, Beijing, China

为了解北京市丰台区诺如病毒感染者的流行病学特征及相关食品暴露风险,预防诺如病毒的感染和健康教育提供依据。本研究纳入2017-2021年北京市丰台区食源性疾病监测数据,采用描述性流行病学方法对诺如病毒感染者的流行病学特征、临床症状和食品暴露因素进行分析。2017-2021年丰台区共采集612份腹泻临床标本开展诺如病毒检测,诺如病毒检出率为19.6%(120/612),其中GⅠ检出率为4.7%(29/612),GⅡ检出率为14.9%(91/612)。丰台地区全年均有诺如病毒检出,不同季度的诺如病毒检出率的差异具有统计学意义(χ^(2)=17.838,P<0.05),第一季度和第二季度的检出率显著高于第三季度。不同性别、年龄组和职业间诺如病毒检出率差异均无统计学意义(χ^(2)=0.331,P=0.565)、(χ^(2)=10.541,P=0.194)、(χ^(2)=14.606,P=0.054)。出现恶心(24.35%,56/230)和呕吐(33.54%, 55/164)症状患者中诺如病毒检出率差异有统计学意义(χ^(2)=27.574,P<0.001;χ^(2)=24.35,P<0.05)。暴露不同食品类型的诺如病毒检出检出率差异无统计学意义(χ^(2)=10.525,P=0.215)。暴露于餐饮服务业食品(27.06%, 23/85)和预包装类食品(32%, 8/25)的诺如病毒检出率较高。2017-2021年北京市丰台区诺如病毒监测病例以GⅡ基因组为主,人群普遍易感;流行高峰分布在第一季度和第二季度,呕吐和恶心症状可以作为诺如病毒感染者的指示性临床特征。

We wished to:(i) understand the epidemiological characteristics and related risks of food exposure of norovirus-infected persons in Fengtai District(FD;Beijing, China);(ii) provide a basis for the prevention of norovirus infection;(iii) provide health education. We included surveillance data on foodborne diseases in FD during 2017 – 2021. Descriptive methods were used to analyze the epidemiological characteristics, clinical symptoms, and food-exposure factors of norovirus-infected patients. From 2017 to 2021, 612 clinical specimens were collected in FD for surveillance of foodborne diseases. The overall prevalence of norovirus detection was 19.6%(120/612), of which the prevalence of detection(PoD) for the GⅠ genogroup was 4.7%(29/612) and that for the GⅡ genogroup was 14.9%(91/612). Noroviruses were detected throughout the year in FD, and the PoD of noroviruses in different quarters of the year was significant (χ^(2) = 17.838, P < 0.05). The PoD during the first and second quarters was significantly higher than that in the third quarter. There was no significant difference in the PoD of noroviruses among different sexes, age groups, or occupations (χ^(2) = 0.331, P =0.565;χ^(2) = 10.541, P = 0.194;χ^(2) = 14.606, P = 0.054). Significant differences in the PoD of noroviruses among patients with symptoms of nausea(24.35%, 56/230) and vomiting(33.54%, 55/164) were observed (χ^(2) = 27.574, P < 0.001;χ^(2) = 24.35, P < 0.05). There was no significant difference in the PoD of noroviruses among different types of foodborne exposure (χ^(2) = 10.525, P = 0.215). Exposure to food from the catering-service industry(27.06%, 23/85) and prepackaged food(32%, 8/25) harbored a relatively high PoD of noroviruses. The norovirus-surveillance cases in FD during 2017– 2021 were derived mainly from the GⅡ genogroup, and the population was, in general, susceptible to norovirus infection. The epidemic peak was distributed in the first and second quarters. Vomiting and nausea symptoms could be indicative clinical characteristics of norovirus-infected patients.