Evidence map›Paper›PMID 39825399›Full record

ArticleBMC research notes2025

Onchocerciasis is not a major cause of blindness in two endemic villages in Sierra Leone.

Ibrahim Kargbo-Labour, Victoria Redwood-Sawyerr, Abdulai Conteh, Doris Harding, Mohamed S Bah, Patricia Houck, Sugandh Juneja, Achille Kabore, Darin Evans, Angela M Weaver and 1 more

Abstract read
In one paragraph

Article in BMC research notes, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Ibrahim Kargbo-LabourNational Neglected Tropical Disease Control Programme, Ministry of Health, Freetown, Sierra Leone.
Victoria Redwood-SawyerrHelen Keller International, Freetown, Sierra Leone.
Abdulai ContehNational Neglected Tropical Disease Control Programme, Ministry of Health, Freetown, Sierra Leone.
Doris HardingCentral Public Health Reference Laboratory, Ministry of Health, Freetown, Sierra Leone.
Mohamed S BahHelen Keller International, Freetown, Sierra Leone.
Patricia HouckHelen Keller International, New York, USA.
Sugandh JunejaHelen Keller International, Freetown, Sierra Leone.
Achille KaboreFHI 360, Washington, DC, USA.
Darin EvansUnited States Agency for International Development, Washington, DC, USA.
Angela M WeaverHelen Keller International, New York, USA.
Yaobi ZhangHelen Keller International, New York, USA. yzhang@hki.org.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveSierra 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.

resultsReported 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.

Indexed as

BlindnessEndemic DiseasesOnchocerciasisOnchocerciasis, OcularAdolescentAdultAnimalsChildChild, PreschoolFemaleHumansIvermectinMaleMiddle AgedSierra LeoneYoung AdultIvermectinOnchocerciasisOv-16 IgG4 antibodiesSierra LeoneSkin snipVision loss

Identifiers

PMID39825399
PMCPMC11748601

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.