Meleko Asrat, Li Sarah, Turgeman Dorin Brener, Bruck Michal, Kesete Nisan Z, Zaadnoordijk Willemijn, Rollinson David, Sabar Galia, Bentwich Zvi, Golan Rachel
NALA, Carlebach 29, Tel Aviv-Yafo 6713224, Israel.
Department of Public Health, Mizan Tepi University College of Medicine and Health Sciences, Tepi 5160, Ethiopia.
Trop Med Infect Dis. 2022 Sep 28;7(10):272. doi: 10.3390/tropicalmed7100272.
Introduction: Schistosomiasis, a neglected tropical disease (NTD), remains a public health problem in Ethiopia. Freshwater snails, acting as intermediate hosts, release cercariae, the infectious parasite, into the water, which penetrate human skin that encounters infested waters. The objective of this study was to map snail abundance along rivers and study its association with schistosomiasis infection in communities using these rivers. Materials and Methods: A cross-sectional study was carried out at 20 river sites in Mizan Aman city administration, Bench Sheko zone, South West Ethiopia Peoples (SWEP) region, Ethiopia, to study the distribution of host snails and transmission sites for intestinal schistosomiasis. This study used a quantitative database consisting of data on the prevalence of infected snails, the characteristics of rivers and riverbanks, and the prevalence of schistosomiasis in the community, based on stool samples collected from community members near the sampling sites. Results: Aquatic snails were found in 11 of the 20 sites sampled. A total of 598 snails was collected, including Biomphalaria pfeifferi, Biomphalaria sudanica, Radix natalensis and Bulinus globosus species; the most abundant species was Biomphalaria pfeifferi. Stool samples were collected from 206 community members from all 20 sites. Forty-one (19.9%) were positive for Schistosoma mansoni. A positive correlation was found between the presence of snails and positive stool samples (r = 0.60, p = 0.05) and between the presence of infected snails and the prevalence of infection (r = 0.64, p = 0.03). Locations with muddy riverbanks were associated with the presence of snails (r = 0.81, p < 0.001). Conclusions: These results emphasize the importance of mapping snails for the control of schistosomiasis by defining hotspots of infection and identifying factors associated with the presence of infected snails. The results support the need for a continuous mapping of snails and the introduction of snail control as a major element for the successful control of schistosomiasis in endemic communities.
血吸虫病作为一种被忽视的热带病，在埃塞俄比亚仍是一个公共卫生问题。淡水螺作为中间宿主，会将具有传染性的寄生虫尾蚴释放到水中，尾蚴可穿透接触受感染水域的人体皮肤。本研究的目的是绘制河流沿线螺类的丰度图，并研究其与使用这些河流的社区中血吸虫病感染的关联。
在埃塞俄比亚西南部人民（SWEP）地区本奇谢科州米赞阿曼市行政区的20个河流站点开展了一项横断面研究，以研究肠道血吸虫病的中间宿主螺类分布及传播地点。本研究使用了一个定量数据库，该数据库包含感染螺类的患病率数据、河流及河岸特征数据，以及基于从采样点附近社区成员采集的粪便样本得出的社区血吸虫病患病率数据。
在20个采样点中的11个发现了水生螺类。共采集到598只螺，包括费氏双脐螺、苏丹双脐螺、纳塔尔萝卜螺和球茎小泡螺；其中数量最多的是费氏双脐螺。从所有20个站点的206名社区成员中采集了粪便样本。41人（19.9%）曼氏血吸虫检测呈阳性。发现螺类的存在与粪便样本呈阳性之间存在正相关（r = 0.60，p = 0.05），感染螺类的存在与感染率之间也存在正相关（r = 0.64，p = 0.03）。河岸泥泞的地点与螺类的存在相关（r = 0.81，p < 0.001）。
这些结果强调了通过确定感染热点和识别与感染螺类存在相关的因素来绘制螺类分布图对于控制血吸虫病的重要性。结果支持持续绘制螺类分布图并引入螺类控制措施作为在流行社区成功控制血吸虫病的主要要素的必要性。
