Kargbo-Labour Ibrahim, Redwood-Sawyerr Victoria, Conteh Abdulai, Harding Doris, Bah Mohamed S, Houck Patricia, Juneja Sugandh, Kabore Achille, Evans Darin, Weaver Angela M, Zhang Yaobi
National Neglected Tropical Disease Control Programme, Ministry of Health, Freetown, Sierra Leone.
Helen Keller International, Freetown, Sierra Leone.
BMC Res Notes. 2025 Jan 17;18(1):21. doi: 10.1186/s13104-024-07051-9.
Sierra Leone, a country where onchocerciasis is endemic in 14 of the 16 districts, was the focus of our investigation. Despite 17 rounds of annual ivermectin treatment since 2005, a report circulated by a local politician indicated an increase in cases of suspected onchocerciasis-related vision impairment in two villages (Mangobo and Petifu) in Tonkolili district. In response, the National Neglected Tropical Disease Program conducted a comprehensive investigation. Ophthalmological, parasitological, and serological tests were conducted using standard procedures to determine the relationship between self-reported vision loss and onchocerciasis in adults. In addition, serological tests were carried out on children aged 5 to 9 years to assess the recent status of exposure to onchocerciasis in the two villages.
Reported vision loss in 37 patients was mainly due to cataracts (35.1%), allergic conjunctivitis (18.9%), refractive error (10.8%), and other conditions not related to onchocerciasis. There were 40.7% of all adults (N = 54) tested and 29.0% of 31 persons with self-reported vision loss who were positive for Ov-16 IgG4 antibodies, suggesting a history of exposure to onchocerciasis. However, otoscopic eye examinations and microscopic skin snip tests were all negative for Onchocerca volvulus microfilariae, indicating no active or low-intensity infection among adults and a low or zero risk of serious ocular morbidity in the two villages. Onchocerciasis may no longer be a major cause of blindness in these two villages. Apparently, 4.6% of 153 children aged 5 to 9 years tested positive for Ov-16 IgG4 antibodies, suggesting that onchocerciasis transmission is likely still ongoing in the two villages. The data presented here suggest that more annual rounds of mass treatment with ivermectin with high coverage are needed to eliminate onchocerciasis transmission in this area.
塞拉利昂是一个在16个区中有14个区盘尾丝虫病呈地方性流行的国家，是我们此次调查的重点。自2005年以来，尽管进行了17轮年度伊维菌素治疗，但一名当地政治家散发的一份报告显示，通科利利区的两个村庄（曼戈博和佩蒂富）疑似盘尾丝虫病相关视力损害病例有所增加。作为回应，国家被忽视热带病项目开展了一项全面调查。采用标准程序进行眼科、寄生虫学和血清学检测，以确定成人自我报告的视力丧失与盘尾丝虫病之间的关系。此外，对5至9岁儿童进行了血清学检测，以评估这两个村庄近期盘尾丝虫病暴露情况。
报告的37例视力丧失主要归因于白内障（3�.1%）、过敏性结膜炎（18.9%）、屈光不正（10.8%）以及其他与盘尾丝虫病无关的病症。在所有接受检测的成人（N = 54）中，有40.7%以及在31名自我报告视力丧失的人员中有29.0%的人Ov-16 IgG4抗体呈阳性，表明有盘尾丝虫病暴露史。然而，耳镜眼部检查和皮肤微型切片镜检中盘尾丝虫微丝蚴均为阴性，表明成人中无活动性或低强度感染，且这两个村庄严重眼部发病风险较低或为零。盘尾丝虫病可能不再是这两个村庄失明的主要原因。显然，在153名5至9岁儿童中，有4.6%的人Ov-16 IgG4抗体检测呈阳性，这表明这两个村庄的盘尾丝虫病传播可能仍在继续。此处呈现的数据表明，需要进行更多轮次的高覆盖率年度伊维菌素群体治疗，以消除该地区的盘尾丝虫病传播。
