Article

Ivermectin for onchocercal eye disease (river blindness)

Hode Internal Medicine, Texas, USA. .
Cochrane database of systematic reviews (Online) (Impact Factor: 6.03). 08/2012; 8(8):CD002219. DOI: 10.1002/14651858.CD002219.pub2
Source: PubMed

ABSTRACT

Onchocerciasis is caused by tiny worms and is transmitted from person to person by a small biting fly. The fly breeds in fast flowing rivers and streams mainly in West Africa. The disease causes severe itching and thickening of the skin and damages structures at the front and back of the eye. It also affects the nerve that connects the eye with the brain. Four studies based in west Africa were included in the review; two small studies in Ghana and Liberia and two larger community-based ones in Nigeria and Sierra-Leone. In the smaller studies, people with onchocercal infection were given one dose of ivermectin or placebo and followed up for one year. In the larger studies all individuals in selected communities were treated every six or 12 months with ivermectin or placebo, whether or not they were infected, and followed for two to three years. This review found that ivermectin can prevent damage to the front of the eye but its effectiveness in preventing blindness remains uncertain.

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    • "The number of individuals with visual impairment or low vision (defined as corrected visual acuity of <18/60 and ≥3/60 in the better eye [47]) caused by onchocerciasis was estimated using a published ratio of 1.78 visual impairment to blindness [47]. Prevalent blindness and visual impairment cases were assumed to be irreversible conditions unresponsive to ivermectin treatment [49], which does not reverse established ocular sequelae (also including sclerosing keratitis and optic nerve atrophy). "
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    • "(OR = 1.91, 95% CL = 1.59À2.28). Other parasites that may impact on vision include Plasmodium falciparum, Taenia solium , Echinococcus granulosus and Onchocerca volvulus (Benazzou et al., 2010; Ziaei et al., 2011; Ejere et al., 2012; Postels et al., 2013). 4.3. "
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    • "The incidence of optic neuritis is also significantly reduced.37,99 However, there is controversy over the impact on visual acuity, with a Cochrane review suggesting that there is no effect on this parameter.100 This seems consistent with the findings of Kennedy et al who followed mectizan users for five years and found no changes in the prevalence of main ocular lesions in this cohort.101 "
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