Skip to main content
The British Journal of Ophthalmology logoLink to The British Journal of Ophthalmology
. 1993 Jan;77(1):30–32. doi: 10.1136/bjo.77.1.30

Visual loss in an onchocerciasis endemic community in Sierra Leone.

J A Whitworth 1, C E Gilbert 1, D M Mabey 1, D Morgan 1, A Foster 1
PMCID: PMC504418  PMID: 8435395

Abstract

The visual acuities of 1625 individuals recruited to a community-based clinical trial of ivermectin in southern Sierra Leone were measured, and the prevalence of visual loss in this rural population where onchocerciasis is hyperendemic was determined. Ocular examination was performed before treatment to establish the cause of visual loss. Using WHO definitions, 1.3% were blind (less than 3/60 in both eyes), 4.3% were visually impaired (between 6/24 and 3/60 in the better eye), and a further 3.4% were uniocularly blind (less than 3/60 in one eye and better than 6/24 in the other). Cataract and onchocerciasis were the major causes of visual loss in this population. More than half of the ocular morbidity was preventable or treatable by public health measures or basic curative medicine. These findings are discussed in the light of the available health and eye care services.

Full text

PDF
30

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ayanru J. O. Blindness in the Midwestern State of Nigeria. Trop Geogr Med. 1974 Sep;26(3):325–332. [PubMed] [Google Scholar]
  2. Brown K. R., Neu D. C. Ivermectin--clinical trials and treatment schedules in onchocerciasis. Acta Leiden. 1990;59(1-2):169–175. [PubMed] [Google Scholar]
  3. Chirambo M. C., Tielsch J. M., West K. P., Jr, Katz J., Tizazu T., Schwab L., Johnson G., Swartwood J., Taylor H. R., Sommer A. Blindness and visual impairment in southern Malawi. Bull World Health Organ. 1986;64(4):567–572. [PMC free article] [PubMed] [Google Scholar]
  4. Dadzie K. Y., Rolland A., Thylefors B. The evolution of ocular onchocerciasis in the Volta River Basin Area over a period of five years of vector control. Tropenmed Parasitol. 1984 Mar;35(1):41–46. [PubMed] [Google Scholar]
  5. Faal H., Minassian D., Sowa S., Foster A. National survey of blindness and low vision in The Gambia: results. Br J Ophthalmol. 1989 Feb;73(2):82–87. doi: 10.1136/bjo.73.2.82. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. McMahon J. E., Davies J. B., White M. D., Goddard J. M., Beech-Garwood P. A., Kirkwood B. R. Onchocerciasis in Sierra Leone. I. Studies on the prevalence and transmission at Gbaiima village. Trans R Soc Trop Med Hyg. 1986;80(5):802–809. doi: 10.1016/0035-9203(86)90389-5. [DOI] [PubMed] [Google Scholar]
  7. Post R. J., Crosskey R. W. The distribution of the Simulium damnosum complex in Sierra Leone and its relation to onchocerciasis. Ann Trop Med Parasitol. 1985 Apr;79(2):169–194. doi: 10.1080/00034983.1985.11811905. [DOI] [PubMed] [Google Scholar]
  8. Semba R. D., Murphy R. P., Newland H. S., Awadzi K., Greene B. M., Taylor H. R. Longitudinal study of lesions of the posterior segment in onchocerciasis. Ophthalmology. 1990 Oct;97(10):1334–1341. doi: 10.1016/s0161-6420(90)32413-2. [DOI] [PubMed] [Google Scholar]
  9. Stilma J. S., Bridger S. Causes and prevalence of blindness in the Northern Province of Sierra Leone. Doc Ophthalmol. 1983 Dec 15;56(1-2):115–122. doi: 10.1007/BF00154717. [DOI] [PubMed] [Google Scholar]
  10. Taylor H. R. Ivermectin treatment of ocular onchocerciasis. Acta Leiden. 1990;59(1-2):201–206. [PubMed] [Google Scholar]
  11. Thylefors B., Duppenthaler J. L. Epidemiological aspects of intraocular pressure in an onchocerciasis endemic area. Bull World Health Organ. 1979;57(6):963–969. [PMC free article] [PubMed] [Google Scholar]
  12. Whitworth J. A., Gilbert C. E., Mabey D. M., Maude G. H., Morgan D., Taylor D. W. Effects of repeated doses of ivermectin on ocular onchocerciasis: community-based trial in Sierra Leone. Lancet. 1991 Nov 2;338(8775):1100–1103. doi: 10.1016/0140-6736(91)91963-u. [DOI] [PubMed] [Google Scholar]
  13. Whitworth J. A., Morgan D., Maude G. H., Downham M. D., Taylor D. W. A community trial of ivermectin for onchocerciasis in Sierra Leone: clinical and parasitological responses to the initial dose. Trans R Soc Trop Med Hyg. 1991 Jan-Feb;85(1):92–96. doi: 10.1016/0035-9203(91)90173-v. [DOI] [PubMed] [Google Scholar]

Articles from The British Journal of Ophthalmology are provided here courtesy of BMJ Publishing Group

RESOURCES