目的 了解2016-2019年江西省土源性线虫病国家监测点人群感染情况,为全省制订土源性线虫病防治策略、评价防治效果提供科学依据。方法 2016-2019年在全省11个县（市）设立国家监测点,并按照《全国肝吸虫病和土源性线虫病监测方案（试行）》开展监测。监测点以县为单位按地理方位划分为东、西、南、北、中5个片区,每个片区抽取1个乡镇的1个行政村开展监测,监测点4年固定不变。每个行政村整群抽取3周岁以上常住居民不少于200人,每个监测点不少于1 000人。收集被调查者粪样,采用改良加藤厚涂片法（一粪二检）检测土源性线虫感染情况,计算感染率和感染度等指标;钩虫卵阳性粪样以试管滤纸培养法进行钩蚴培养,鉴定钩虫种类。感染率间比较采用卡方检验。每个行政村随机抽取5户家庭,每户采集1份田地或菜园的土样,其中350 g用于钩蚴检测,50 g用于人蛔虫卵检测。采用5%盐水进行土壤钩蚴镜检鉴定;用饱和硝酸钠漂浮法检测土壤中人蛔虫卵。结果 11个监测点生产方式均以农业为主,饮用水以自来水和井水为主。2016-2019年无害化厕所覆盖率分别为78.4%（30 443/38 817）、80.7%（32 856/40 723）、85.6%（35 301/41 258）和91.0%（37 964/41 730）,不同年份间差异有统计学意义（P < 0.01）。2016-2019年11个监测点人群土源性线虫感染率分别为1.6%（175/11 126）、1.4%（160/11 203）、 0.8%（91/11 183）和1.3%（151/11 197）;感染率总体呈下降趋势,2019年较2016年下降了14.1%,不同年份间差异有统计学意义（P < 0.01）。4年南丰县人群土源性线虫感染率分别为4.7%（48/1 016）、3.8%（39/1 034）、2.6%（27/1 028）和7.4%（75/1 010）,均高于其他县（P < 0.01）。人群钩虫感染率呈现年间波动,从2016年的1.0%（116/11 126）降至2018年0.6%(70/11 183),2019年再升至1.0%(112/11 197),各年度间差异有统计学意义（P < 0.01）。除2016年外,各年度女性土源性线虫和钩虫感染率均高于男性。4年钩虫感染者中,美洲钩虫感染构成比分别为92.2%（71/77）、91.0%（61/67）、97.8%（44/45）和91.8%（89/97）,其次为混合感染,单纯十二指肠钩虫感染较少。人群蛔虫感染率总体呈下降趋势,从2016年的0.5%（53/11 126）下降至2019年的0.3%（29/11 197）,各年度间差异有统计学意义（P < 0.01）。4年鞭虫感染率分别为0.1%（6/11 126）、0.1%（14/11 203）、0.1%（9/11 183）和0.1%（10/11 197）。4年土壤样本蛔虫卵检出率分别为9.1%（25/275）、1.8%（5/275）、1.8%（5/275）和1.5%（4/275）,各年度间差异有统计学意义（P < 0.01）。土壤中人蛔虫卵与钩蚴检出率均呈逐年下降趋势。结论 江西省人群土源性线虫感染率与中、重度感染者比例总体逐年下降,呈低度流行态势。钩虫仍是今后土源性寄生虫病防治的重点虫种,南丰县是今后防控的重点地区。

Objective To understand the epidemic status of soil-transmitted helminth (STH) infection in the national surveillance sites in Jiangxi Province during 2016-2019, in order to provide scientific basis for formulating control strategy and evaluating the control effect. Methods National surveillance sites were set up in 11 counties (cities) in Jiangxi Province during 2016-2019, and surveillance was carried out according to the national clonorchiasis and soil-borne nematode surveillance program (provisional version). According to geographical location, each county at surveillance was divided into 5 areas, i.e. east, west, south, north and center areas. From a township of each area, an administrative village was selected as the surveillance site for 4 scheduled years, and no less than 200 permanent residents at age of 3 years or above were cluster sampled from each administrative village, while no less than 1 000 residents totaled from each surveillance site. Fecal samples were collected from the enrolled residents and were examined for STH eggs(two slide-reading/one sample) using the modified Kato-katz thick smear method to estimate infection rate and intensity. The samples of hookworm egg positive were further examined by test-tube filter paper incubation for larva to identify the species. The infection rate between groups was compared by the Chi-square test. Five households were randomly selected in each administrative village to collect soil sample in field or vegetable garden. From each household, 350 g soil was used for hookworm larva detection, and 50 g for Ascaris egg detection. The hookworm larvae in soil were identified by microscopy using 5% saline; the hookworm larvae in soil were detected using the saturated sodium nitrate floatation method. Results The production mode of the 11 surveillance sites were mainly the agricultural mode, and the types of drinking water were mainly tap water and well water. From 2016 to 2019, the coverage rates of sanitary toilets were 78.4% (30 443/38 817), 80.7% (32 856/40 723), 85.6% (35 301/41 258), and 91.0% (37 964/41 730), respectively. The differences between years were statistically significant (P < 0.01). The STH infection rate in the population in the 4 years was 1.6% (175/11 126), 1.4% (160/11 203), 0.8% (91/11 183) and 1.3% (151/11 197), respectively. The infection rate showed an overall downward trend, with a decrease of 14.1% in 2019 compared with 2016; the differences between the years were statistically significant (P < 0.01). The infection rate of STH in Nanfeng county was 4.7% (48/1 016), 3.8% (39/1 034), 2.6% (27/1 028) and 7.4% (75/1 010) in the 4 years, respectively, which were significantly higher than other counties (P < 0.01). The hookworm infection rate fluctuated from 1.0% (116/11 126) in 2016 to 0.6% (70/11 183) in 2018, and then increased to 1.0% (112/11 197) in 2019. The difference was statistically significant between the years (P < 0.01). The infection rates of STH and hookworm in females was higher than that in males, except in 2016. Among the hookworm infected, Necator americanus accounted for 92.2% (71/77), 91.0% (61/67), 97.8% (44/45) and 91.8% (89/97) identified by hookworm larva culture in the 4 years, respectively, while the rest of cases were mixed infection, and single Ancylostoma duodenale infection. The infection rate of Ascaris lumbricoides decreased from 0.5% (53/11 126) in 2016 to 0.3% (29/11 197) in 2019, showing an overall trend of decrease; the differences between years were statistically significant (P < 0.01). The infection rate of Trichuris trichiura was 0.1% (6/11 126), 0.1% (14/11 203), 0.1% (9/11 183) and 0.1% (10/11 197), respectively. The positive rate of Ascaris eggs in soil samples in the 4 years was 9.1% (25/275), 1.8% (5/275), 1.8% (5/275) and 1.5% (4/275), respectively; the differences were statistically significant(P < 0.01). The positive rates of Ascaris eggs and hookworm larvae in soil samples both showed a decreasing trend. Conclusion The STH infection rate and the proportions of moderate and severe infection showed a trend of decrease year by year, displaying a low prevalent status. Hookworm remains the key target parasite, and Nanfeng county the key area for STH control in the future.