A Controlled Study of the Ocular Findings in Liberian Subjects with Microfilariae of Onchocerca Volvulus at the Outer Canthus of the Eye

Abstract

Summary Onchocercal blindness and ocular lesions of onchocerciasis in Liberia are reported for the first time. The order of frequency of onchocercal lesions was as follows: iridocyclitis, complicated cataract, cataract in the young, and secondary glaucoma. Microfilariae of Onchocerca volvulus were found in the anterior chamber of the eye in 11.8% of 143 subjects with onchocercomata and positive skin biopsies at the outer canthus of the eye. Live microfilariae were recorded within the lens, possibly for the first time. Onchocercal pannus was infrequent. The absence of trachoma in Liberia is noted. Punctate keratitis in Liberia is believed to be of viral origin in the majority of cases; however, predilection of the lesions to the limbal area is suggestive of the co-existence of onchocerciasis.