The impact of Merowe Dam on Simulium hamedense vector of onchocerciasis in Abu Hamed focus - Northern Sudan

Particle and Fibre Toxicology

Tarig B Higazi¹  Nabil Aziz⁴  Tong Chor M Deran³  Kamal Hashim³  Wigdan A ElMubarak⁵  Hanan A Mohamed⁵  Sara A Abuelmaali⁶  Arwa H Elaagip²  Isam MA Zarroug⁵ 

[1] Ohio University, Zanesville, Ohio, USA;Department of Parasitology and Medical Entomology, Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan;National Programme for Prevention of Blindness (NPPB), Federal Ministry of Health, Khartoum, Sudan;The Carter Center, Khartoum, Sudan;Onchocerciasis Control/Elimination Programme, National Programme for Prevention of Blindness (NPPB), Federal Ministry of Health, Khartoum, Sudan;Department of Medical Entomology, National Public Health Laboratory, Federal Ministry of Health, Khartoum, Sudan

关键词: Sudan;    Simulium hamedense;    Abu Hamed focus;    Merowe Dam;    Elimination;    Onchocerciasis;   

Others  :  807377
DOI  :  10.1186/1756-3305-7-168

 received in 2014-01-12, accepted in 2014-04-01,  发布年份 2014

【 摘 要 】

Background

Abu Hamed, the northernmost onchocerciasis focus in the world, is located along the River Nile banks in the Nubian Desert. Hydroelectric dams can alter activity of black flies and may provide breeding sites for black fly. Merowe Dam, the largest hydropower project in Africa, was built west of Abu Hamed focus in 2009. The impact of the Dam on onchocerciasis and its black fly vectors in Abu Hamed focus was measured in this study.

Findings

Entomological surveys for aquatic stages and adult Simulium hamedense were conducted before and after the inception of Merowe Dam in 2007/2008 and 2010/2011. There was no black fly breeding or adult activity in the previously known breeding sites upstream of the Merowe Dam with the western most breeding site found in AlSarsaf village near the center of the focus. No adult or aquatic stages of black flies were found downstream of the Dam.

Conclusions

The artificial lake of the Dam flooded all the breeding sites in the western region of the focus and no aquatic stages and/or adult black fly activity were established in the study area upstream of the Dam. The Dam seems to have positive impact on onchocerciasis and its black fly vectors in Abu Hamed focus. These outcomes of the Merowe Dam might have contributed to the recently declared interruption of onchocerciasis transmission in Abu Hamed focus. Continuous entomological surveys are needed to monitor presence of black fly vectors and its impact on the disease.

【 授权许可】

   
2014 Zarroug et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

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