Reduction of Urogenital Schistosomiasis with an Integrated Control Project in Sudan

Purpose
Schistosomiasis remains a major public health concern in Sudan, particularly Schistosoma haematobium infection. This study presents the disease-reduction outcomes of an integrated control program for schistosomiasis in Al Jabalain locality of White Nile State, Sudan from 2009 through 2011.
Methods
The total population of the project sites was 482,902, and the major target group for intervention among them was 78,615 primary school students. For the cross-sectional study of the prevalence, urine and stool specimens were examined using the urine sedimentation method and the Kato cellophane thick smear method, respectively. To assess the impacts of health education for students and a drinking water supply facility at Al Hidaib village, questionnaire survey was done.
Results
The overall prevalence for S. haematobium and S. mansoni at baseline was 28.5% and 0.4%, respectively. At follow-up survey after 6–9 months post-treatment, the prevalence of S. haematobium infection was reduced to 13.5% (95% CI = 0.331–0.462). A higher reduction in prevalence was observed among girls, those with moderately infected status (around 20%), and residents in rural areas, than among boys, those with high prevalence (>40%), and residents in urban areas. After health education, increased awareness about schistosomiasis was checked by questionnaire survey. Also, a drinking water facility was constructed at Al Hidaib village, where infection rate was reduced more compared to that in a neighboring village within the same unit. However, we found no significant change in the prevalence of S. mansoni infection between baseline and follow-up survey (95% CI = 0.933–6.891).
Conclusions
At the end of the project, the prevalence of S. haematobium infection was reduced by more than 50% in comparison with the baseline rate. Approximately 200,000 subjects had received either praziquantel therapy, health education, or supply of clean water. To consolidate the achievements of this project, the integrated intervention should be adapted continuously.

一、研究目的
血吸虫病（Schistosomiasis）仍是苏丹面临的重大公共卫生问题，其中尤以埃及血吸虫（Schistosoma haematobium）感染为甚。本研究呈现了2009年至2011年间，苏丹白尼罗河州阿尔贾巴莱恩地区（Al Jabalain locality）血吸虫病综合防控项目的疾病负担降低效果。

二、研究方法
本项目覆盖区域的总人口为482902人，其中干预的主要目标人群为78615名小学生。针对感染率的横断面研究中，分别采用尿沉渣法检测尿液标本、加藤厚涂片法（Kato cellophane thick smear method）检测粪便标本。为评估针对学生的健康教育以及阿尔海代卜村（Al Hidaib village）供水设施建设的干预效果，本研究开展了问卷调查。

三、研究结果
基线时，埃及血吸虫与曼氏血吸虫（Schistosoma mansoni）的总体感染率分别为28.5%与0.4%。治疗后6至9个月的随访调查显示，埃及血吸虫感染率降至13.5%（95%置信区间（Confidence Interval，CI）=0.331–0.462）。相较于男生、高感染率群体（感染率>40%）与城市居民，女生、中度感染人群（感染率约20%）及农村居民的感染率降幅更为显著。健康教育开展后，通过问卷调查证实受试者对血吸虫病的认知水平有所提升。此外，阿尔海代卜村建成了供水设施，该村的感染率降幅较同区域内的邻近村庄更为明显。但本研究未观察到基线与随访调查间曼氏血吸虫感染率存在显著变化（95%置信区间（Confidence Interval，CI）=0.933–6.891）。

四、研究结论
项目结束时，埃及血吸虫感染率较基线水平降低了50%以上。约20万名受试者接受了吡喹酮（praziquantel）治疗、健康教育或清洁供水服务。为巩固本项目成果，后续应持续优化综合防控干预措施。