Université de Nouakchott, Faculté des Sciences et Techniques, UR génomes et milieux, Nouakchott, Mauritanie.
Aix Marseille Univ, AP-HM, SSA, RITMES, Marseille, France.
PLoS Negl Trop Dis. 2024 Sep 25;18(9):e0012505. doi: 10.1371/journal.pntd.0012505. eCollection 2024 Sep.
Urogenital schistosomiasis due to Schistosoma haematobium is a major public health problem in Mauritania, but little is known about its epidemiology in many areas of the country, particularly in the lake zones. The objectives of the present parasitological and malacological study were to assess the prevalence and intensity of urogenital schistosomiasis among school children in Kankossa and Oued Rawdha lakes, southern Mauritania, and determine the species of intermediate host snails and the prevalence of snails with schistosome.
A school-based epidemiological survey was conducted in two villages in the lake areas of Kankossa and Oued Rawdha. Urine samples were collected from 450 state primary school children and Koranic school children and examined for the presence of S. haematobium eggs using filtration technique. Water bodies adjacent to human settlement were surveyed for Bulinus and Biomphalaria snails that may potentially be intermediate hosts of S. haematobium. Morphological, molecular, and proteomic (i.e. matrix-assisted laser desorption ionization time-of-flight mass spectrometry [MALDI-TOF MS]) identification of collected snails were conducted, and their infection status was assessed by real-time polymerase chain reaction (RT-PCR) using the highly repetitive DraI gene.
The prevalence of urogenital schistosomiasis was 35.6% and 15.8% in Kankossa and Oued Rawdha villages, respectively, corresponding to 'moderate' prevalence (i.e., 10-49% infected schoolchildren). Urogenital schistosomiasis prevalence was higher in boys (30.0%) than in girls (21.2%; P < 0.05), and in Koranic schools pupils (37.1%) than in state schools (20.5%; P < 0.05) pupils. Multiple regression analysis showed that sex (odds ratio [OR]: 1.64; 95% confidence interval [95% CI]: 1.06-2.57; P = 0.03) and Koranic school level (OR: 1.79; 95% CI: 1.06-3.04; P = 0.03) were independently and significantly associated with urogenital schistosomiasis. Based on molecular and proteomic identification, both B. senegalensis and B. umbilicatus colonized the water bodies of Oued Rawdha, whereas both B. forskalii and B. truncatus colonized those of Kankossa. The DraI RT-PCR detected S. haematobium complex DNA in 8 of 66 (12.1%) analysed snails: one B. truncatus and one B. forskalii in Kankossa and five B. senegalensis and one B. umbilicatus in Oued Rawdha.
Urogenital schistosomiasis is moderately prevalent in the lake zones of Kankossa and, to a lesser extent, Oued Rawdha, located in southern Mauritania. Mass drug administration campaigns with praziquantel should be conducted to reduce the prevalence of urogenital schistosomiasis among school-aged children in the lake zone of Kankossa and Oued Rawdha village. Further parasitological and malacological studies should be conducted in other villages located in the Mauritanian lakes in the southern Sahelian zones and the northern oasis areas to strengthen our knowledge of the current epidemiological situation and implement appropriate urogenital schistosomiasis control strategies.
曼丁哥语毛里塔尼亚的尿路血吸虫病是一个主要的公共卫生问题，由于埃及血吸虫引起，但该国许多地区，特别是湖泊地区，对其流行病学了解甚少。本寄生虫学和软体动物学研究的目的是评估南部坎科萨和乌德劳德哈湖泊地区在校儿童中尿路血吸虫病的流行率和严重程度，并确定中间宿主蜗牛的种类以及感染血吸虫的蜗牛的流行率。
在坎科萨和乌德劳德哈湖区的两个村庄进行了基于学校的流行病学调查。从 450 名公立小学和古兰经学校的儿童收集尿液样本，并使用过滤技术检查是否存在埃及血吸虫卵。对靠近人类住区的水体进行调查，以寻找可能是埃及血吸虫中间宿主的布利纳斯和比马法利亚蜗牛。对采集的蜗牛进行形态学、分子学和蛋白质组学（即基质辅助激光解吸电离飞行时间质谱 [MALDI-TOF MS]）鉴定，并通过实时聚合酶链反应（RT-PCR）使用高度重复的 DraI 基因评估其感染状况。
坎科萨和乌德劳德哈村的尿路血吸虫病患病率分别为 35.6%和 15.8%，属于“中度”流行（即 10-49%受感染的学龄儿童）。与女孩（21.2%；P<0.05）相比，男孩（30.0%）尿路血吸虫病患病率更高，与公立学校学生（20.5%；P<0.05）相比，古兰经学校学生的患病率更高。多因素回归分析显示，性别（比值比[OR]：1.64；95%置信区间[95%CI]：1.06-2.57；P=0.03）和古兰经学校水平（OR：1.79；95%CI：1.06-3.04；P=0.03）与尿路血吸虫病独立且显著相关。基于分子和蛋白质组学鉴定，布氏塞内加尔蜗牛和比马法利亚蜗牛都在乌德劳德哈的水体中定殖，而布氏福斯卡利蜗牛和布氏 truncatus 则在坎科萨的水体中定殖。DraI RT-PCR 在 66 个分析蜗牛中的 8 个（12.1%）中检测到埃及血吸虫复合体 DNA：一个布氏 truncatus 和一个布氏福斯卡利蜗牛在坎科萨，五个布氏塞内加尔蜗牛和一个比马法利亚蜗牛在乌德劳德哈。
在毛里塔尼亚南部的坎科萨和乌德劳德哈湖地区，尿路血吸虫病呈中度流行。应开展大规模药物治疗运动，用吡喹酮治疗坎科萨和乌德劳德哈湖地区学龄儿童的尿路血吸虫病。应在南部萨赫勒地区和北部绿洲地区的其他毛里塔尼亚湖泊村庄进行进一步的寄生虫学和软体动物学研究，以加强我们对当前流行情况的了解，并实施适当的尿路血吸虫病控制策略。
