Abstract: Objective　To understand the prevalence of soil?borne nematode infections among residents living in urban/town areas of China, so as to provide insights into the control and elimination of soil?borne nematodiasis. Methods　A total of 5 epidemic areas were classified in China according to the prevalence of human Clonorchis sinensis infections captured from the 2014–2015 national survey on major human parasitic diseases in China, and the total sample size was estimated according to the binomial distribution and Poisson’s distribution. Then, the total sample size was allocated proportionally to each province (autonomous region, municipality) of China based on the percentage of residents living in urban and town areas, and the number of survey sites in each province (autonomous region, municipality) was proportionally assigned according to the percentages of residents living in urban and town areas. Then, stratified sampling was performed at county, township and community levels according to the number of sampling sites in each province (autonomous region, municipality), and the survey site (community) was defined as the smallest sampling unit. All permanent residents in the survey sites were selected as the study subjects, and their stool samples were collected for identification and counting of parasite egg using a Kato?Katz technique. The prevalence and intensity of each parasite species were calculated. Results　From 2014 to 2015, among the 133 231 residents detected in 31 provinces (autonomous regions, municipalities) of China, the overall prevalence of soil?borne nematode infections was 1.23% (1 636/133 231), and the prevalence rates of hookworm, Ascaris?lumbricoides and?Trichuris trichiura infections were 0.77% (1 032/133 231), 0.32% (426/133 231) and 0.17% (224/133 231), respectively. The highest prevalence of soil?borne nematode infections was seen in Jiangxi (4.03%, 82/2 034) and Chongqing (4.03%, 524/13 012), followed by in Hainan (3.47%, 72/2 075). The prevalence of soil?borne nematode infections was 1.07% (662/62 139) in men and 1.37% (974/71 092) in women, and the greatest prevalence was found in residents at ages of 65 to 70 years (2.56%, 219/8 569). With regard to occupations and education levels, herdsmen (2.47%, 2/81) and illiterate residents (3.33%, 226/6 795) were found to have the highest prevalence of soil?borne nematode infections, respectively. In addition, mild infections were predominantly identified in hookworm?, A.?lumbricoides? and?T. trichiura?infected individuals (all > 90%). Conclusions　The overall prevalence of soil?borne nematodiasis remains low in urban and town areas of China; however, human infections are widespread. According to the epidemiological features, health education combined with deworming are recommended to reduce the prevalence of soil?borne nematode infections among residents living in urban and town areas of China.

Key words: Soil?borne nematodiasis, Urban and town areas, Hookworm, Ascaris lumbricoides, Trichuris trichiura, China

摘要： 目的　了解我国城镇地区居民土源性线虫病流行状况，为土源性线虫病防控与消除提供参考。方法　根据2014–2015年全国人体重点寄生虫病现状调查，按人群华支睾吸虫感染率将全国划分为5类流行区，采用二项分布和泊松分布计算总样本量，将总样本量按城镇人口占比等比例分配到各省份，各省份调查点数再按辖区城区和镇区人口占比等比例分配。各省份根据调查点数，自县（市、区）、乡（镇、街道）和居委会分级抽样，调查点（居委会）为最小抽样单位。以调查点内常住人口作为调查对象，收集其粪便标本，采用改良加藤厚涂片法（1粪2检）鉴别土源性线虫虫卵并计数，计算各虫种感染率及感染度。结果　2014–2015年，全国31个省（自治区、直辖市）共调查城镇居民133 231人，土源性线虫感染率为1.23%（1 636/133 231），其中钩虫、蛔虫和鞭虫感染率分别为0.77%（1 032/133 231）、0.32%（426/133 231）和0.17%（224/133 231）。全国城镇居民土源性线虫感染率以江西省（82/2 034）和重庆市（524/13 012）最高，均为4.03%；其次为海南省，感染率为3.47%（72/2 075）。男、女性居民土源性线虫感染率分别为1.07%（662/62 139）和1.37%（974/71 092）。土源性线虫感染率以65～70岁年龄组居民最高，为2.56%（219/8 569）；各职业中，以牧民感染率最高[2.47%（2/81）]；不同文化程度居民中，以文盲感染率最高[3.33%（226/6 795）]。钩虫、蛔虫和鞭虫轻度感染者所占比例均＞ 90%。结论　我国城镇居民土源性线虫病流行总体处于较低水平，但分布较广泛。针对城镇地区土源性线虫病流行特点，可采取健康教育和药物驱虫相结合的措施，以降低居民感染率。

关键词: 土源性线虫病, 城镇地区, 钩虫, 蛔虫, 鞭虫, 中国