Abstract: Objective　To investigate the current prevalence of human intestinal protozoal infections in Tibet Autonomous Region, so as to provide the scientific basis for the development of the future control strategy. Methods　The study sites were sampled using a stratified cluster random sampling method in different ecological zones and different geographical locations of Tibet Autonomous Region in 2015. Fecal samples were collected from the permanent residents at ages of 3 years and older for the detection of intestinal protozoa cysts and trophozoites. The region?, gender?, age?, occupation? and education level?specific prevalence of human intestinal protozoal infections was estimated and compared. Results　A total of 70 study sites were sampled from 23 counties (districts) in 3 ecological zones of Tibet Autonomous Region in 2015. Among 17 939 subjects surveyed, there were 1 117 residents infected with intestinal protozoa, with a prevalence of 6.23%. There were 9 species of intestinal protozoa identified, and Entamoeba coli (3.59%), Giardia lamblia (0.74%) and Blastocystis hominis (0.72%) were found to have a high infection rate. The prevalence of human intestinal protozoal infections was 7.20%, 6.39% and 4.48% in the southern, eastern and northern Tibetan ecological zones, respectively. Among the 23 counties (districts), the highest human prevalence was seen in Baingoin (13.56%) and Amdo counties (12.77%), and there were significant differences in the prevalence of human intestinal protozoal infections among the three ecological zones (χ2 = 33.909, P < 0.01) and 23 counties (districts) (χ2 = 580.511, P < 0.01). There was no gender?specific prevalence of human intestinal protozoal infections (men, 6.08%; women, 6.35%; χ2 = 0.542, P > 0.05); however, there was age?specific human prevalence (χ2 = 44.377, P < 0.01), and a higher prevalence was seen in residents at ages of 60－69 years (8.51%) and 50－59 years (7.67%). In addition, there were occupation? (χ2 = 37.568, P < 0.01) and education level?specific prevalence rates of human intestinal protozoal infections (χ2 = 14.659, P < 0.01), and a higher prevalence was seen in farmers (7.17%) and herdsmen (5.28%), and in residents with a primary school education (6.62% and illiterate residents (6.33%). Conclusions　The prevalence of human intestinal protozoal infections remains high in Tibet Autonomous Region. The health education pertaining to intestinal parasitic disease control requires to be intensified among farmers and herdsmen in rural areas.

Key words: Intestinal protozoa, Cross?sectional study, Tibet Autonomous Region

摘要： 目的　了解西藏自治区人体肠道原虫感染现状，为制定防治对策提供科学依据。方法　2015年采取分层整群随机抽样方法，在西藏自治区不同类型生态区和不同地理方位抽取调查点，采集≥ 3周岁常住居民粪便样本，检测肠道原虫包囊和滋养体，对检测结果进行描述性流行病学分析。结果　2015年，西藏自治区共在3个生态区抽取了23个县（区）70个调查点。共调查居民17 939人，发现各类肠道原虫感染者1 117例，人群肠道原虫感染率为6.23%。共检出9种原虫，其中以结肠内阿米巴、蓝氏贾第鞭毛虫、人芽囊原虫感染率较高，分别为3.59%、0.74%和0.72%。藏南山地生态区、藏东?川西生态区和藏北高原高寒生态区人群肠道原虫感染率分别为7.20%、6.39%和4.48%；不同县（区）中，以斑戈县和安多县人群感染率较高，分别为13.56%和12.77%。不同生态区和不同县（区）人群肠道原虫感染率差异均有统计学意义（χ2 = 33.909、580.511，P 均 ＜ 0.01）。男性和女性肠道原虫感染率分别为6.08%和6.35%，差异无统计学意义（χ2 = 0.542，P > 0.05）；不同年龄组人群感染率差异有统计学意义（χ2 = 44.377，P ＜ 0.01），其中以60～、50～岁组人群感染率较高，分别为8.51%和7.67%。不同职业和文化程度人群感染率差异均有统计学意义（χ2 = 37.568、14.659，P均 ＜ 0.01），其中分别以农民和牧民、小学和文盲人群感染率较高，分别为7.17%和5.28%、6.62%和6.33%。结论　西藏自治区人群肠道原虫感染率仍然较高，今后应进一步加强对农村等重点地区、农牧民等重点人群的健康教育工作。 　

关键词: 肠道原虫, 现况调查, 西藏自治区