Objective: To investigate the epidemiological characteristics and spatial distribution characteristics of Clonorchis sinensis human infections in Guangdong Province from 2016 to 2022, so as to provide insights into formulation of the clonorchiasis control measures in the province.
Methods: Xinhui District of Jiangmen City, Longmen County of Huizhou City and Wengyuan County of Shaoguan City in Guangdong Province were selected as fixed surveillance sites for human clonorchiasis from 2016 to 2022, and additional 10% to 15% counties (districts) endemic for clonorchiasis were sampled from Guangdong Province as mobile surveillance sites each year from 2016 to 2022. A village (community) was randomly selected from each surveillance site according to the geographical orientations of east, west, south, north and middle, and subjects were randomly sampled from each village (community). C. sinensis eggs were detected in subjects' stool samples using the Kato-Katz technique, and the prevalence and intensity of C. sinensis infections were calculated. In addition, subjects' gender, age, ethnicity, educational level and occupation were collected. The Guangdong Provincial 1:1 million electronic map in vector format was downloaded from the National Geomatics Center of China, and kernel density analysis and spatial autocorrelation analysis of C. sinensis human infections in Guangdong Province from 2016 to 2022 were performed using the software ArcGIS 10.7.
Results: A total of 153 188 residents were tested for C. sinensis infections in Guangdong Province from 2016 to 2022, including 75 596 men (49.35%) and 77 592 women (50.65%), and there were 5 369 residents infected with C. sinensis, with 3.50% overall prevalence of infections. The prevalence rates of severe, moderate and mild C. sinensis infections were 0.76%, 7.26% and 91.97% among C. sinensis-infected residents in Guangdong Province from 2016 to 2022, and there were age-, gender-, ethnicity-, occupation- and educational level-specific prevalence of C. sinensis human infections (χ2 = 2 578.31, 637.33, 52.22, 2 893.28 and 1 139.33, all P values < 0.05). Global spatial autocorrelation analysis showed a cluster in the prevalence of C. sinensis human infections in Guangdong Province (Moran's I = 0.63, Z = 27.31, P < 0.05). Kernel density analysis showed that the prevalence of C. sinensis human infections with a high kernel density in Guangdong Province was mainly distributed along the Zhujiang River basin in Pearl River Delta areas, followed by in eastern and northern Guangdong Province. In addition, local spatial autocorrelation analysis identified 73 high-high clusters of the prevalence of C. sinensis human infections in Guangdong Province.
Conclusions: The prevalence of C. sinensis human infections was high in Guangdong Province from 2016 to 2022, and mild infection was predominant among all clonorchiasis cases, with spatial clusters identified in the prevalence of C. sinensis human infections. Targeted clonorchiasis control measures are required among high-risk populations and areas.
［摘要］ 目的分析2016—2022年广东省华支睾吸虫感染人群流行病学和空间分布特征, 为当地制定华支睾吸虫病防治措施提供参考。方法2016—2022年, 选取广东省江门市新会区、惠州市龙门县和韶关市翁源县等作为人群华支睾吸虫病固定监测点, 另外每年选取10% ~ 15%的华支睾吸虫病流行县 (市、区) 作为流动监测点。各监测点按照东、西、南、北、中5个地理方位, 每个方位选取1个行政村 (社区) 随机抽取调查对象, 采用Kato-Katz法检测调查对象粪样中华支睾吸虫虫卵, 计算感染率和感染度, 同时收集调查对象性别、年龄、民族、教育程度、职业等信息。于国家基础地理信息中心下载广东省1∶100万矢量电子地图, 采用ArcGIS 10.7软件进行核密度分析、空间自相关分析等空间统计分析和可视化制图。结果2016—2022年, 广东省累计对153 188名居民进行华支睾吸虫感染调查, 其中男性75 596名 (占49.35%), 女性77 592名 (占50.65%); 检出华支睾吸虫感染5 369例, 感染率为3.50%, 其中重、中度和轻度感染者分别占0.76%、7.26% 和91.97%。不同年龄、性别、民族、职业、文化程度人群华支睾吸虫感染率差异均有统计学意义 (χ 2 = 2 578.31、637.33、52.22、2 893.28和1 139.33, P 均< 0.05) 。全局空间自相关分析发现, 广东省人群华支睾吸虫感染率存在聚集性分布 (Moran’s I = 0.63, Z = 27.31, P < 0.05); 核密度分析发现, 广东省人群华支睾吸虫感染率核密度高值主要分布于珠江三角洲地区珠江流域, 其次分布于粤东地区和粤北地区; 局部空间自相关分析发现73处华支睾吸虫感染率高-高聚集区。结论2016—2022年广东省人群华支睾吸虫感染率较高, 且以轻度感染为主, 具有空间聚集性; 应对重点人群和区域有针对性地制定华支睾吸虫病防控措施。.
Keywords: Clonorchiasis sinensis; Epidemiological characteristic; Guangdong Province; Spatial cluster; Surveillance.