Evaluating epilepsy management in an onchocerciasis-endemic area: Case of Maridi, South Sudan.

PURPOSE: The epilepsy prevalence in Maridi County, South Sudan, in 2018 was 43.8 (95% CI: 40.9-47.0) per 1000 persons; 85.2% of the identified persons with epilepsy (PWE) met the criteria of onchocerciasis-associated epilepsy. To address this health problem, an epilepsy clinic was established at Maridi County Hospital in 2020. In August 2023, the impact of the clinic on the lives of PWE and their families was evaluated. METHODS: At the Maridi epilepsy clinic, data routinely collected by primary healthcare workers as part of patient care was reviewed. We also analyzed findings from two household surveys conducted in 2018 and 2022, which assessed the impact of the clinic on epilepsy care. Moreover, four households, each with four PWE, were visited in a high epilepsy prevalence area. PWE were examined by a neurologist, and in-depth interviews were conducted with family members. RESULTS: The proportion of PWE on anti-seizure medication increased by 39.7% (95%CI: 35.3-44.2) between 2018 and 2022. The proportion of PWE reporting daily seizures decreased from 27.3% in 2018 to 5.3% in 2022. Of the 754 PWE seen in the clinic in July 2023, only 17 (2.3%) reported side effects. During household visits in July 2023, 13/173 (7.5%) of the visited PWE were found without remaining anti-seizure medication. A high level of epilepsy-related stigma was observed in all visited households. CONCLUSION: The Maridi epilepsy clinic positively impacted the lives of PWE in Maridi. Similar initiatives should be accessible for all PWE living in onchocerciasis-endemic areas. Evidence-based information about OAE is needed to decrease misconceptions and epilepsy-related stigma.

Impact of annual community-directed treatment with ivermectin on the incidence of epilepsy in Mvolo, a two-year prospective study.

OBJECTIVES: The potential impact of cumulative community-directed treatment with ivermectin (CDTI) on epilepsy epidemiology in Mvolo County, South Sudan, an onchocerciasis-endemic area with high epilepsy prevalence, was investigated. Annual CDTI was introduced in 2002 in Mvolo, with interruptions in 2016 and 2020. METHODS: Comprehensive house-to-house surveys in Mvolo (June 2020 and 2022) identified cases of epilepsy, including probable nodding syndrome (pNS). Community workers screened households in selected sites for suspected epilepsy, and medical doctors confirmed the diagnosis and determined the year of seizure onset. The incidence of epilepsy, including pNS, was analysed using 95% confidence intervals (CIs). Data on ivermectin intake and onchocerciasis-associated manifestations (itching and blindness) were collected. RESULTS: The surveys covered 15,755 (2020) and 15,092 (2022) individuals, identifying 809 (5.2%, 95% CI: 4.8-5.5%) and 672 (4.5%, 95% CI: 4.1-4.8%) epilepsy cases, respectively. Each survey reported that a third of the surveyed population experienced skin itching, and 3% were blind. Epilepsy incidence per 100,000 person-years gradually declined, from 326.5 (95% CI: 266.8-399.1) in 2013-2015 to 96.6 (95% CI: 65.5-141.7) in 2019-2021. Similarly, pNS incidence per 100,000 person-years decreased from 151.7 (95% CI: 112.7-203.4) to 27.0 (95% CI: 12.5-55.5). Coverage of CDTI was suboptimal, reaching only 64.0% of participants in 2019 and falling to 24.1% in 2021 following an interruption in 2020 due to COVID-19 restrictions. Additionally, while 99.4% of cases had active epilepsy in 2022, less than a quarter of these had access to antiseizure medication. CONCLUSIONS: The observed decrease in epilepsy incidence despite suboptimal CDTI coverage highlights the potential impact of onchocerciasis control efforts and underscores the need to strengthen these efforts in Mvolo County and across South Sudan. As a proactive measure, Mvolo and neighbouring counties are transitioning to biannual CDTI. Furthermore, the substantial epilepsy treatment gap in Mvolo should be addressed.

Treatment and prevention of epilepsy in onchocerciasis-endemic areas is urgently needed.

BACKGROUND: There is increasing epidemiological evidence supporting the association between onchocerciasis and seizures, reinforcing the concept of onchocerciasis-associated epilepsy (OAE). The aim of this paper is to provide an update on the new knowledge about OAE and to propose recommendations to the World Health Organization how to address this public health problem. MAIN TEXT: During the 2nd International Workshop on OAE held on 19-21 September, 2023, in Antwerp, Belgium, participants recognised OAE as a substantial yet neglected public health problem, particularly in areas of sub-Saharan Africa where onchocerciasis remains hyperendemic. Evidence from prospective population-based studies suggest that strengthening onchocerciasis elimination efforts leads to a significant reduction of OAE incidence. There is a need to validate an OAE case definition to estimate the burden of disease and identify onchocerciasis-endemic areas requiring intensification of onchocerciasis elimination programmes and integration of epilepsy care. It is expected that raising awareness about OAE will boost the population uptake of ivermectin. The implementation of a community-based epilepsy treatment programme offering free anti-seizure medications (ASMs) has shown high effectiveness in reducing the frequency of seizures and improving the overall quality of life of people with epilepsy. CONCLUSIONS: To reduce OAE burden, enhanced collaboration between onchocerciasis and mental health programmes at community, national, and international levels is required. Urgent efforts are needed to ensure the uninterrupted provision of free ASMs in onchocerciasis-endemic areas. Furthermore, OAE should be included in the quantification of the onchocerciasis disease burden.

Accessibility to formal education among persons with epilepsy in Mahenge, Tanzania.

BACKGROUND: Epilepsy is estimated to affect 50 million people globally, with 80% living in sub-Saharan Africa (SSA). Children with epilepsy (CWE) in SSA are often socially isolated, and many do not get access to school. This study aimed to explore the barriers hindering accessibility to formal education among CWE in Mahenge, Tanzania. METHODS: The study was conducted in June 2022 in four villages (Mdindo, Msogezi, Mzelezi and Sali) using quantitative and qualitative methods. The quantitative included 203 persons with epilepsy (PWE), while the qualitative involved six focus group discussions and 17 in-depth interviews. Quantitative and qualitative data were analyzed using Stata and Nvivo software, respectively. RESULTS: Of the 203 PWE, 62 (30.5%) had never enrolled in school, while 77 (54.6%) of those enrolled dropped-out before completing it. The perceived barriers to accessing education were categorized as individual barriers (such as frequent seizures, learning difficulties, anti-seizure medication side effects and perceived stigma), Community barriers (such as stigma and discrimination, negative beliefs and misconceptions, relocation to farms and poor socio-economic status), and Institutional barriers (including lack of knowledge about epilepsy among stake-holders, topography and distance to schools). CONCLUSION: There is a high rate of dropouts and non-enrolment of CWE in schools within the Mahenge area. Negative beliefs and low awareness of the community about epilepsy and formal education contribute to this issue. This calls for more advocacy to raise community awareness on epilepsy. The government should enforce an inclusive education policy and provide free and uninterrupted anti-seizure medication for seizure control.

Mortality among persons with epilepsy in onchocerciasis-endemic and non-endemic areas of sub-Saharan Africa: A systematic review and meta-analysis.

PURPOSE: To document epilepsy-related mortality in sub-Saharan Africa (SSA) and investigate possible associations with onchocerciasis endemicity. METHODS: Systematic review with meta-analysis. Searches were performed in PubMed and Google Scholar (search terms: 'epilepsy'; 'mortality/death'; 'sub-Saharan Africa'). Included studies were classified as high-risk or low-risk for onchocerciasis based on documented endemicity data. Pooled mortality rates and annual case fatality rates (CFR) were calculated, and risk factors for mortality among persons with epilepsy (PWE) were investigated using meta-regression analysis. RESULTS: The 28 eligible studies reported 30 epilepsy surveys, of which 9 (30.0%) were conducted in onchocerciasis high-risk sites. The pooled epilepsy mortality rate was 20.9 (95% CI: 5.9-74.4) per 100,000 person-years, and the pooled CFR was 36.2 (95% CI: 23.9-54.4) per 1,000 PWE per year, albeit with substantial between-study heterogeneity. Compared to onchocerciasis low-risk sites, high-risk sites had higher pooled mortality (342.9 versus 10.0 per 100,000 PY; p<0.001) and CFR (57.0 versus 26.6 per 1,000 PWE per year; p = 0.001). Mortality of PWE was almost five-fold that of people without epilepsy (mortality risk ratio: 4.9; 95% CI: 3.5-6.8). Studies in onchocerciasis high-risk sites and the study which recruited only PWE with nodding syndrome were associated with higher CFR (p = 0.044 and p = 0.002, respectively). The leading causes of epilepsy-related death were status epilepticus (58.5%), drowning (15.7%), and sudden unexpected death in epilepsy (10.1%). CONCLUSION: Epilepsy mortality remains high in SSA. Most reported causes of death among PWE might be averted by improving seizure control. Better epilepsy prevention and care are urgently needed, particularly in onchocerciasis-endemic settings.

Disability assessment among persons with epilepsy in Mahenge, an onchocerciasis-endemic area in Tanzania: A cross-sectional study.

BACKGROUND: A high prevalence of epilepsy has been observed in the onchocerciasis-endemic focus of Mahenge, Tanzania. This study sought to assess the degree of disability experienced by persons with epilepsy (PWE) in Mahenge and identify associations with sociodemographic and clinical features. METHOD: This cross-sectional study was conducted in Mahenge, Tanzania, between February and July 2020. PWE were recruited from the Mahenge epilepsy clinic and four neighbouring rural villages (Mdindo, Mzogezi, Mzelezi and Sali). Data were collected using the 36-item version of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) questionnaire for adults. For children aged 5-17 years, we used the Module on Child Functioning developed by UNICEF and the Washington Group. Questionnaires were administered by trained research assistants. Descriptive statistics were performed, and multivariable analyses (gamma and logistic regressions) were conducted. RESULTS: A total of 321 adults (45.5% males) and 48 children (55.3% males) with epilepsy participated. The overall median WHODAS 2.0 score was 4.8% (IQR: 0.9-18.9). The most affected disability domain was 'participating in the society' (median score: 12.5%, IQR: 0-29.2). Fifteen (31.3%) of the children with epilepsy had a disability in at least one domain of the child functioning module, with the 'accepting change' domain harbouring the highest proportion of disabled children (12.5%). Higher seizure frequency and longer epilepsy duration were associated with more disability. CONCLUSION: PWE in Mahenge experience variable degrees of disability. The affected domains indicate the need for societal rehabilitation of PWE in various community and/or social activities. Peer-support groups were instituted at the study sites to address these needs.

Effect of onchocerciasis elimination measures on the incidence of epilepsy in Maridi, South Sudan: a 3-year longitudinal, prospective, population-based study.

BACKGROUND: High onchocerciasis transmission predisposes endemic communities to a high epilepsy burden. The 4·4% epilepsy prevalence documented in 2018 in Maridi, South Sudan, prompted the strengthening of onchocerciasis elimination measures. Community-directed treatment with ivermectin was implemented annually in 2017, 2018, and 2019, interrupted in 2020, and re-implemented biannually in 2021. We aimed to assess the effect of these interventions, along with slash and clear vector control on the incidence of epilepsy, including nodding syndrome. METHODS: In this longitudinal, prospective, population-based study, we did a two-stage house-to-house epilepsy survey before (May 10-30, 2018) and after (March 9-19, 2022) the strengthening of onchocerciasis elimination interventions in South Sudan. Strengthening also included the implementation of a community-based slash and clear vector control method that we initiated in 2019 at the Maridi dam (the main blackfly breeding site). Eight sites were surveyed near the Maridi dam and inclusion required residence in one of these sites. All household residents were first screened by community workers, followed by confirmation of the epilepsy diagnosis by trained clinicians. The primary outcome was epilepsy incidence, including nodding syndrome, which was assessed via self-reported new-onset epilepsy in the previous 4 years of each survey, confirmed by clinician assessment. FINDINGS: The preintervention survey included 17 652 people of whom 736 had epilepsy (315 female and 421 male), and the post-intervention survey included 14 402 people of whom 586 had epilepsy (275 female and 311 male). When biannual community-directed treatment with ivermectin was initiated in 2021, the intervention's coverage rose by 15·7% (95% CI 14·6-16·8); although only 56·6% of the population took ivermectin in 2021. Between 2018 and 2022, epilepsy incidence decreased from 348·8 (307·2-395·8) to 41·7 (22·6-75·0) per 100 000 person-years. Similarly, the incidence of nodding syndrome decreased from 154·7 (127·6-187·3) to 10·4 (2·7-33·2) per 100 000 person-years. The identified risk factors for epilepsy were: living closer to the Maridi dam, being aged between 6 and 40 years, not taking ivermectin, and being male. INTERPRETATION: In onchocerciasis-endemic areas with high epilepsy prevalence, strengthening onchocerciasis elimination interventions can decrease the incidence of epilepsy, including nodding syndrome. Additional efforts are needed to increase community-directed treatment with ivermectin coverage and sustain blackfly control in Maridi. FUNDING: Research for Health in Humanitarian Crisis, European Research Council, Research Foundation-Flanders, Research Foundation-Flanders, the Italian Agency for Development Cooperation, and La Caixa Foundation.

Nodding syndrome, a case-control study in Mahenge, Tanzania: Onchocerca volvulus and not Mansonella perstans as a risk factor.

BACKGROUND: Nodding syndrome (NS) has been consistently associated with onchocerciasis. Nevertheless, a positive association between NS and a Mansonella perstans infection was found in South Sudan. We aimed to determine whether the latter parasite could be a risk factor for NS in Mahenge. METHODS: Cases of epilepsy were identified in villages affected by NS in Mahenge, Tanzania, and matched with controls without epilepsy of the same sex, age and village. We examined blood films of cases and controls to identify M. perstans infections. The participants were also asked for sociodemographic and epilepsy information, examined for palpable onchocercal nodules and onchocerciasis-related skin lesions and tested for anti-Onchocerca volvulus antibodies (Ov16 IgG4) by ELISA. Clinical characteristics of cases and controls, O. volvulus exposure status and relevant sociodemographic variables were assessed by a conditional logistic regression model for NS and epilepsy status matched for age, sex and village. RESULTS: A total of 113 epilepsy cases and 132 controls were enrolled, of which, respectively, 56 (49.6%) and 64 (48.5%) were men. The median age in cases and controls was 28.0 (IQR: 22.0-35.0) and 27.0 (IQR: 21.0-33.3) years. Of the persons with epilepsy, 43 (38.1%) met the probable NS criteria and 106 (93.8%) had onchocerciasis-associated epilepsy (OAE). M. perstans infection was absent in all participants, while Ov16 seroprevalence was positively associated with probable NS (odds ratio (OR): 5.05, 95%CI: 1.79-14.27) and overall epilepsy (OR: 2.03, 95%CI: 1-07-3.86). Moreover, onchocerciasis-related skin manifestations were only found in the cases (n = 7, p = 0.0040), including persons with probable NS (n = 4, p = 0.0033). Residing longer in the village and having a family history of seizures were positively correlated with Ov16 status and made persons at higher odds for epilepsy, including probable NS. CONCLUSION: In contrast to O. volvulus, M. perstans is most likely not endemic to Mahenge and, therefore, cannot be a co-factor for NS in the area. Hence, this filaria is unlikely to be the primary and sole causal factor in the development of NS. The main risk factor for NS remains onchocerciasis.

Quality of life of persons with epilepsy in Mahenge, an onchocerciasis-endemic area in Tanzania: A cross-sectional study.

OBJECTIVE: This study investigated the quality of life (QoL) of adults with epilepsy living in Mahenge, an onchocerciasis-endemic area in Tanzania with a high prevalence of onchocerciasis-associated epilepsy (OAE). METHODS: Between February and December 2020, persons with epilepsy (PWE) were recruited from four rural villages in Mahenge: Mdindo, Msogezi, Mzelezi, and Sali. For PWE who could not answer the questionnaire due to their mental or physical disability, a family member was asked to answer the questions instead. The Quality of Life in Epilepsy Inventory-31 (QOLIE-31) questionnaire used contained seven domains. The raw domain scores were transformed to 0-100% subscales, with higher scores indicating better QoL. The global QoL was calculated from the subscales using the overall QOLIE-31 score formula. RESULTS: In total, 96 PWE were enrolled in the study with a median age of 28 (range: 18-60) years, of whom 45 (47%) were male. The questionnaires were answered by PWE (54.8%) or one of their family members (45.2%). Most PWE were single (81%), and half never attended school. About two-thirds (65%) of PWE were suspected of having OAE, and a third (31%) had a history of head nodding seizures. Most PWE were treated with phenobarbital (85.4%) and had high treatment adherence (96.9%). Still, the number of seizures per week ranged from 0 to 7, with a median of one. The mean global QOLIE-31 score was 66.9 (range: 38.3-92.1) out of 100.0. Predictors of lower QoL were living in Sali Village and experiencing seizures the week before the interview. In contrast, completing primary school and switching to second-line anti-seizure medication were predictors of higher QoL. CONCLUSION: In order to improve the QoL of PWE in Mahenge, it is vital to optimize anti-seizure medication regimens to decrease the frequency of seizures and to increase the schooling of PWE.

Impact of a bi-annual community-directed treatment with ivermectin programme on the incidence of epilepsy in an onchocerciasis-endemic area of Mahenge, Tanzania: A population-based prospective study.

BACKGROUND: Community-directed treatment with ivermectin (CDTi) is used to eliminate onchocerciasis. However, despite 25 years of annual CDTi in Mahenge, Tanzania, the prevalence of onchocerciasis and onchocerciasis-associated epilepsy remained high in certain rural villages. Therefore, in 2019, bi-annual CDTi was introduced in the area. This study assessed the impact of the programme on the incidence of epilepsy in four villages. METHODOLOGY: Door-to-door epilepsy surveys were conducted prior to (2017/18) and after (2021) implementing a bi-annual CDTi program. All household members were screened for epilepsy symptoms using a validated questionnaire, and suspected cases were examined by a medical doctor to confirm/reject the diagnosis of epilepsy. The prevalence and annual incidence of epilepsy, including nodding syndrome, were calculated with 95% Wilson confidence intervals with continuity correction. The latter was also done for CDTi coverage in 2016 and 2021. RESULTS: Precisely 5,444 and 6,598 persons were screened for epilepsy before and after implementing the intervention. The CDTi coverage of the overall population was 82.3% (95%CI: 81.3-83.2%) in 2021 and sustained in both distribution rounds (81.5% and 76.8%). The coverage was particularly high in children and teenagers aged 6 to 18 years (93.2%, 95%CI: 92.1-94.2%). The epilepsy prevalence remained similar: 3.3% (95%CI: 2.9-3.9%) in 2017/18 versus 3.1% (95%CI: 2.7-3.5%) in 2021. However, the incidence of epilepsy declined from 177.6 (95%CI: 121.2-258.5) in 2015-2017 and 2016-2018 to 45.5 (95%CI: 22.2-89.7) in 2019-2021 per 100,000 persons-years. The incidence of probable nodding syndrome varied from 18.4 (95%CI: 4.7-58.5) to 5.1 (95%CI: 0.3-32.8). None of the nine incidence cases of epilepsy for which information on ivermectin intake was available took ivermectin in the year they developed their first seizures. CONCLUSION: A bi-annual CDTi programme should be implemented in areas with high prevalence of onchocerciasis and epilepsy. High CDTi coverage among children is particularly important to prevent onchocerciasis-associated epilepsy.

Onchocerciasis-associated epilepsy: an update and future perspectives.

Onchocerciasis-associated epilepsy (OAE) is an important neglected public health problem in areas with high ongoing onchocerciasis transmission. The risk that children in such areas develop epilepsy is related to their Onchocerca volvulus microfilarial (mf) load. Before the implementation of mass treatment with ivermectin, microfilariae were detected in cerebrospinal fluid (CSF). More recently, neither O. volvulus microfilariae nor DNA were detected in CSF or brain tissue; however, these samples were obtained years after seizure onset. It is possible that during fever-induced increased blood-brain barrier permeability, microfilariae enter the brain and, upon dying, cause an inflammatory reaction inducing seizures. Including OAE in the onchocerciasis disease burden estimation may mobilise extra resources for onchocerciasis disease elimination and treatment/care of OAE-affected persons/families.

Impact of COVID-19 on the well-being of children with epilepsy including nodding syndrome in Uganda: A qualitative study.

OBJECTIVE: To investigate the impact of the COVID-19 pandemic and related restrictions on the access and use of health services by children with epilepsy including nodding syndrome in Uganda. METHODS: Four focus group discussions (FGD) with parents/caregivers of children with epilepsy and five in-depth interviews with key informants were conducted between April and May 2021 at Butabika National Mental Referral Hospital and Kitgum General Hospital. RESULTS: COVID-19-related restrictions, including the halting of non-essential services and activities, and suspension of public transport, created several challenges not only for children with epilepsy and their parents/caregivers but also for their healthcare providers. Study participants described extreme transport restrictions that reduced their access to healthcare care services, increased food insecurity and shortage or inability to afford essential medicines as consequences of COVID-19-related restrictions. However, parents/caregivers and healthcare workers adopted several coping strategies for these challenges. Parents/caregivers mentioned taking on casual work to earn an income to buy food, medicines, and other necessities. Healthcare workers intensified outreach services to affected communities. A positive impact of lockdown measures described by some FGD participants was that most family members stayed at home and were able to care for children with epilepsy in turn. CONCLUSIONS: Our study highlights the significant negative impact of the COVID-19 pandemic and related restrictions on access to health services and the general well-being of children with epilepsy. Decentralized epilepsy treatment services and nutritional support could reduce the suffering of children with epilepsy and their families during the ongoing COVID-19 pandemic and similar future emergencies.

Rapid diagnostic testing for onchocerciasis in Maridi (South Sudan) before and after improving elimination strategies: a repeated cross-sectional survey.

Background: Maridi County is an onchocerciasis-endemic area in South Sudan. Annual community-directed treatment with ivermectin (CDTi) was instituted in Maridi since the early 2000s, but with low coverage. In 2021, the CDTi programme was strengthened to a six-monthly programme. Additionally, the community-based vector control strategy "Slash and Clear" has been implemented since 2019 at the Maridi Dam, the only blackfly breeding site in the area. This study assessed the effect of these reinforced onchocerciasis elimination interventions on the Onchocerca volvulus seroprevalence among young children, an indicator of ongoing transmission. Methods: Baseline and follow-up serosurveys were conducted in Maridi in 2019 (prior to strengthening onchocerciasis elimination efforts) and 2023, respectively. During both surveys, children aged three to nine years were recruited from five study sites situated at different distances from the Maridi Dam. Ov16 antibodies were detected via rapid diagnostic tests (RDTs) using whole blood obtained by finger-pricking the participants. Baseline and follow-up Ov16 prevalence rates were calculated and compared. Results: In 2019, the Ov16 seroprevalence among children aged three to nine years was 24.5% compared to 30.6% in 2023 (p=0.22). Both surveys found a particularly high Ov16 seroprevalence in the study site closest to the Maridi Dam (35.0% in 2019 and 44.0% in 2023, p=0.52). The Ov16 seroprevalence had a non-significant decreasing trend in the three-year-old children, from 12.5% (3/24) in 2019 to 8.8% (3/34) in 2023 (p=0.65). Conclusion: The persistent Ov16 RDT seropositivity among three-year-old children in 2023 indicates ongoing O. volvulus transmission. Therefore, further strengthening of the onchocerciasis elimination programme is required. The study highlights the utility of RDTs in monitoring onchocerciasis transmission in highly endemic settings.

High Prevalence of Glaucoma among Patients in an Onchocerciasis Endemic Area (Mahenge, Tanzania).

Onchocerciasis is known to cause skin lesions and blindness, but there is also epidemiological evidence that onchocerciasis is associated with epilepsy, including nodding syndrome. We carried out ocular exams in persons with epilepsy in Mahenge, an onchocerciasis endemic area with a high prevalence of epilepsy in Tanzania. We recruited 278 consecutive persons with epilepsy attending the epilepsy clinic at Mahenge hospital and satellite clinics in rural villages. They underwent a general physical and a detailed ocular examination and were tested for onchocerciasis Ov16 IgG4 antibodies. Glaucoma was defined by a raised intraocular pressure above 21 mmHg with evidence of typical glaucomatous disc changes in one or both eyes. Among the 278 participants, median age 27 (IQR 21-38) years, 55.4% were female; 151/210 (71.9%) (95% CI: 65.3-77.9) were Ov16 positive. The most frequent ophthalmic lesions were glaucoma (33.1%), vitreous opacities (6.5%) and cataracts (2.9%). In multivariate analysis, glaucoma (adjusted IRR = 1.46; 95% CI: 1.24-1.70) and age (adjusted IRR = 1.01; 95% CI: 1.01-1.02) were significantly associated with onchocerciasis. In conclusion, a high prevalence of glaucoma was observed among Ov16 positive persons with epilepsy. Persons with epilepsy with O. volvulus infection should undergo screening for glaucoma to prevent one of the causes of preventable blindness.