Onchocerciasis-endemic Villages Research Articles

Epidemiology of epilepsy and relationship with onchocerciasis prevalence in villages of the Ntui Health District of Cameroon

BackgroundA strong association between epilepsy and onchocerciasis endemicity has been reported. We sought to document the epidemiology of epilepsy in onchocerciasis-endemic villages of the Ntui Health District in Cameroon and investigate how this relates to the prevalence of onchocerciasis. MethodsIn March 2022, door-to-door epilepsy surveys were conducted in four villages (Essougli, Nachtigal, Ndjame, and Ndowe). Ivermectin intake during the 2021 session of community-directed treatment with ivermectin (CDTI) was investigated in all participating village residents. Persons with epilepsy (PWE) were identified through a two-step approach: administration of a 5-item epilepsy screening questionnaire followed by clinical confirmation by a neurologist. Epilepsy findings were analyzed together with onchocerciasis epidemiological data previously obtained in the study villages. ResultsWe surveyed 1663 persons in the four study villages. The 2021 CDTI coverage for all study sites was 50.9%. Overall, 67 PWE were identified (prevalence of 4.0% (IQR: 3.2–5.1) with one new-onset case during the past 12 months (annual incidence of 60.1 per 100,000 persons). The median age of PWE was 32 years (IQR: 25–40), with 41 (61.2%) being females. The majority (78.3%) of PWE met the previously published criteria for onchocerciasis-associated epilepsy (OAE). Persons with a history of nodding seizures were found in all villages and represented 19.4% of the 67 PWE. Epilepsy prevalence was positively correlated with onchocerciasis prevalence (Spearman Rho = 0.949, p = 0.051). Meanwhile, an inverse relationship was observed between distance from the Sanaga river (blackfly breeding site) and the prevalence of both epilepsy and onchocerciasis. ConclusionThe high epilepsy prevalence in Ntui appears to be driven by onchocerciasis. It is likely that decades of CDTI have likely contributed to a gradual decrease in epilepsy incidence, as only one new case occurred in the past year. Therefore, more effective elimination measures are urgently needed in such endemic areas to curb the OAE burden.

Surveillance for Onchocerciasis-Associated Epilepsy and OV16 IgG4 Testing of Children 6-10 Years Old Should Be Used to Identify Areas Where Onchocerciasis Elimination Programs Need Strengthening.

To eliminate onchocerciasis-associated morbidity, it is important to identify areas where there is still high ongoing Onchocerca volvulus transmission. Between 2015 and 2021, door-to-door surveys were conducted in onchocerciasis-endemic villages in Cameroon, the Democratic Republic of Congo (DRC), Nigeria, South Sudan, and Tanzania to determine epilepsy prevalence and incidence, type of epilepsy and ivermectin therapeutic coverage. Moreover, children aged between six and 10 years were tested for anti-Onchocerca antibodies using the Ov16 IgG4 rapid diagnostic test (RDT). A mixed-effect binary logistic regression analysis was used to assess significantly associated variables of Ov16 antibody seroprevalence. A high prevalence and incidence of epilepsy was found to be associated with a high Ov16 antibody seroprevalence among 6–10-year-old children, except in the Logo health zone, DRC. The low Ov16 antibody seroprevalence among young children in the Logo health zone, despite a high prevalence of epilepsy, may be explained by a recent decrease in O. volvulus transmission because of a decline in the Simulium vector population as a result of deforestation. In the Central African Republic, a new focus of O. volvulus transmission was detected based on the high Ov16 IgG4 seropositivity among children and the detecting of nodding syndrome cases, a phenotypic form of onchocerciasis-associated epilepsy (OAE). In conclusion, Ov16 IgG4 RDT testing of 6–10-year-old children is a cheap and rapid method to determine the level of ongoing O. volvulus transmission and to assess, together with surveillance for OAE, the performance of onchocerciasis elimination programs.

Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites.

In onchocerciasis endemic areas in Africa, heterogenous biting rates by blackfly vectors on humans are assumed to partially explain age- and sex-dependent infection patterns with Onchocerca volvulus. To underpin these assumptions and further improve predictions made by onchocerciasis transmission models, demographic patterns in antibody responses to salivary antigens of Simulium damnosum s.l. are evaluated as a measure of blackfly exposure. Recently developed IgG and IgM anti-saliva immunoassays for S. damnosum s.l. were applied to blood samples collected from residents in four onchocerciasis endemic villages in Ghana. Demographic patterns in antibody levels according to village, sex and age were explored by fitting generalized linear models. Antibody levels varied between villages but showed consistent patterns with age and sex. Both IgG and IgM responses declined with increasing age. IgG responses were generally lower in males than in females and exhibited a steeper decline in adult males than in adult females. No sex-specific difference was observed in IgM responses. The decline in age-specific antibody patterns suggested development of immunotolerance or desensitization to blackfly saliva antigen in response to persistent exposure. The variation between sexes, and between adults and youngsters may reflect differences in behaviour influencing cumulative exposure. These measures of antibody acquisition and decay could be incorporated into onchocerciasis transmission models towards informing onchocerciasis control, elimination, and surveillance.

Community perception of epilepsy and its treatment in onchocerciasis-endemic villages of Maridi county, western equatoria state, South Sudan

ObjectiveTo assess the community’s perception of epilepsy and its treatment in onchocerciasis-endemic villages of Maridi County, Western Equatoria State, South Sudan. The study was conducted prior to the setting up of a community-based intervention to manage the important disease burden caused by onchocerciasis-associated epilepsy in these villages. MethodFive focus group discussions (FGD) were conducted with community leaders and with persons with epilepsy (PWE) and their families between November and December 2019. ResultsVillages close to the Maridi dam were considered to be most affected by epilepsy. Misconceptions about the cause and treatment of epilepsy were identified. Most people believed that epilepsy is caused by bad spirits and is contagious, transmitted through saliva, air, and contact with PWE. Very few participants were aware of the link between onchocerciasis and epilepsy. Persons with epilepsy are restricted in their day-to-day activities and children with epilepsy are often denied going to school. Persons with epilepsy are stigmatized and seen as unfit for marriage. Most participants considered both traditional and medical treatment as ineffective. Uninterrupted anti-seizure treatment continuously was unaffordable for most families with one or more PWE. ConclusionThere is a need to establish a comprehensive epilepsy treatment program which addresses misconceptions about epilepsy and reduces epilepsy-related stigma. Explaining the link between onchocerciasis and epilepsy could lead to a reduction in epilepsy-related stigma.

In pursuit of a cure: The plural therapeutic landscape of onchocerciasis-associated epilepsy in Cameroon - A mixed methods study.

A high prevalence of epilepsy has been observed in several onchocerciasis-endemic villages in the Sanaga River basin, Cameroon. Recent studies suggest that ivermectin, a drug that is distributed annually with the aim of eliminating onchocerciasis, may have a protective effect against acquiring onchocerciasis-associated epilepsy (OAE). This study, therefore, provides an in-depth understanding of both the complex therapeutic landscape for epilepsy as well as the experiences related to the 'community-directed treatment with ivermectin' (CDTI) campaign in order to identify a more trenchant path forward in the fight against epilepsy. Based on a mixed methods study combining a qualitative strand with a quantitative survey, we found that epilepsy was perceived to have had an epidemic emergence in the past and was still considered an important health issue in the study area. Socio-economic status, availability and accessibility of drugs and practitioners, as well as perceived aetiology shaped therapeutic itineraries for epilepsy, which included frequenting (in)formal biomedical health care providers, indigenous and/or faith healing practitioners. Ivermectin uptake for onchocerciasis was generally well known and well regarded. The CDTI faced structural and logistical bottlenecks undermining equal access and optimal adherence to the drug. Locally accessible, uninterrupted, sustainable and comprehensive health-service delivery is essential to help alleviate the epilepsy burden on afflicted households. Addressing structural challenges of CDTI and communicating the potential link with epilepsy to local populations at risk could optimize the uptake of this potentially significant tool in OAE prevention.

Persons with onchocerciasis-associated epilepsy and nodding seizures have a more severe form of epilepsy with more cognitive impairment and higher levels of Onchocerca volvulus infection.

Following previous reports of very high epilepsy prevalence in the onchocerciasis-endemic villages in Maridi County, South Sudan, a study was conducted to investigate the association between the level of Onchocerca volvulus infection, epilepsy, and related outcomes. In December 2018, persons with epilepsy (PWE) were recruited from villages where an epilepsy prevalence of 4.4% (range: 3.5-11.9%) was documented. We enrolled 318 participants from whom two skin snips were taken for microscopic detection of O. volvulus microfilariae (mf). Seizure history was obtained for all PWE and their degree of disability assessed using the modified Rankin scale. Almost all (84.9%) PWE had detectable mf in their skin snips. Onchocerciasis-infected PWE experienced nodding seizures more often than uninfected PWE (p=0.034). Moreover, persons with nodding seizures had more frequent seizures (p<0.001) and higher disability scores (p<0.001), and were more often cognitively impaired and younger at the time of their first epileptic seizure (nine years vs 12 years, p<0.001) compared to PWE without nodding seizures. Based on multivariate models, nodding seizures were associated with higher mf densities (aOR: 1.022; 95%CI: 1.005-1.041). Epilepsy onset at a younger age was associated with a worse outcome. Higher frequency of seizures, longer duration of epilepsy and younger age were associated with increased disability. Regular antiepileptic drug use was associated with better cognitive and disability outcomes. PWE with nodding seizures have a more severe form of onchocerciasis-associated epilepsy, with earlier seizure onset and higher levels of O. volvulus infection. Younger PWE were prone to worse epilepsy outcomes, which would be prevented with regular antiepileptic treatment.

The Role of the Maridi Dam in Causing an Onchocerciasis-Associated Epilepsy Epidemic in Maridi, South Sudan: An Epidemiological, Sociological, and Entomological Study.

Background: An epilepsy prevalence of 4.4% was documented in onchocerciasis-endemic villages close to the Maridi River in South Sudan. We investigated the role of the Maridi dam in causing an onchocerciasis-associated epilepsy epidemic in these villages. Methods: Affected communities were visited in November 2019 to conduct focus group discussions with village elders and assess the OV16 seroprevalence in 3- to 9-year-old children. Entomological assessments to map blackfly breeding sites and determine biting rates around the Maridi River were conducted. Historical data regarding various activities at the Maridi dam were obtained from the administrative authorities. Results: The Maridi dam was constructed in 1954–1955. Village elders reported an increasing number of children developing epilepsy, including nodding syndrome, from the early 1990s. Kazana 2 (the village closest to the dam; epilepsy prevalence 11.9%) had the highest OV16 seroprevalence: 40.0% among children 3–6 years old and 66.7% among children 7–9 years old. The Maridi dam spillway was found to be the only Simulium damnosum breeding site along the river, with biting rates reaching 202 flies/man/h. Conclusion: Onchocerciasis transmission rates are high in Maridi. Suitable breeding conditions at the Maridi dam, coupled with suboptimal onchocerciasis control measures, have probably played a major role in causing an epilepsy (including nodding syndrome) epidemic in the Maridi area.

Onchocerciasis-associated epilepsy in the Democratic Republic of Congo: Clinical description and relationship with microfilarial density.

BackgroundHigh epilepsy prevalence and incidence were observed in onchocerciasis-endemic villages in the Democratic Republic of Congo (DRC). We investigated the clinical characteristics of onchocerciasis-associated epilepsy (OAE), and the relationship between seizure severity and microfilarial density.MethodsIn October 2017, ivermectin-naive persons with epilepsy (PWE) were recruited from onchocerciasis-endemic areas in the Logo health zone in the DRC. Additional PWE were enrolled in the Aketi health zone, where ivermectin had been distributed annually for 14 years. Past medical history, clinical characteristics and skin snips for Onchocerca volvulus detection were obtained from participants. Bivariate and multivariable analyses were used to investigate associations with microfilarial density.ResultsOf the 420 PWE in the Logo health zone, 392 were skin snipped (36.5% positive). Generalized motor seizures were most frequent (392 PWE, 93.3%), and nodding seizures were reported in 32 (7.6%) participants. Twelve PWE (3.1%) presented Nakalanga features. Sixty-three (44.1%) skin snip-positive PWE had a family history of epilepsy, compared to only 82 (32.9%) skin snip-negative PWE (p = 0.027). Eighty-one onchocerciasis-infected PWE were recruited in the Aketi health zone. Positive correlations between seizure frequency and microfilarial density were observed in Logo (Spearman-rho = 0.175; p<0.001) and Aketi (Spearman-rho = 0.249; p = 0.029). In the multivariable model adjusted for age, gender, and previous treatment, high seizure frequency was associated with increasing microfilarial density in Aketi (p = 0.025) but not in Logo (p = 0.148).ConclusionIn onchocerciasis-endemic regions in the DRC, a wide spectrum of seizures was observed. The occurrence of Nodding seizures and Nakalanga features, as well as an association between seizure severity and O. volvulus microfilarial density suggest a high OAE prevalence in the study villages.Trial registrationClinicalTrials.gov NCT03052998.

PO 8576 EFFECT OF IVERMECTIN TREATMENT ON THE FREQUENCY OF SEIZURES IN PERSONS WITH ONCHOCERCIASIS-ASSOCIATED EPILEPSY: PRELIMINARY RESULTS OF A RANDOMISED CLINICAL TRIAL

BackgroundMany studies reported an association between epilepsy and onchocerciasis. Moreover, anecdotal evidence suggests that ivermectin may reduce seizure frequency in persons with onchocerciasis-associated epilepsy (PWOAE). Therefore, we performed a randomised clinical trial among ivermectin-naïve persons with epilepsy in onchocerciasis-endemic villages in the Ituri province, Democratic Republic of the Congo.MethodsPWOAE were randomised in an arm receiving immediate (arm A) or delayed (4 months later) ivermectin treatment (arm B). All participants were receiving anti-epileptic drugs. Inclusion criteria were: age &gt;5 years, signed informed consent, normal neurological development until onset of epilepsy between 5–18 years of age, seizure frequency of ≥2 seizures/month, presence of microfilaria in skin snip and/or antibodies against the Ov16 antigen. Primary study outcome: seizure freedom at month 4; secondary outcome:&gt;50% reduction in seizure frequency at month 4 compared to reported seizure frequency at randomisation. The proposed sample size was 110 PWOAE.Results93 PWOAE, 57 males and 36 females, (mean age 22), were enrolled between October and November 2017. On March 2018, 90 (97%) participant completed their 4th-month evaluation. One serious adverse event was observed during the trial (Steven Johnson reaction caused by phenobarbital). Considering all participants there was no significant difference in outcome between the 2 arms. However, considering participants with presence of microfilariae at enrollment, at month 4, 26/39 (66.6%) in arm A and 20/44 (45.5%) in arm B were seizure free (p=0.05) and a 50% reduction of the number of seizures was observed in 9/39 (23.1% ) in arm A and 7/43 (16.3%) in arm B. (p=0.4).ConclusionIvermectin may have an added value in reducing the frequency of seizures in PWOAE treated with anti-epileptic drugs. However, a larger study is needed to confirm this.

Economic Burden of Epilepsy in Rural Ituri, Democratic Republic of Congo

BackgroundEpilepsy is still very prevalent in Sub-Saharan Africa, particularly in remote, poverty-confronted onchocerciasis-endemic villages. It constitutes a significant burden for the families and communities. However, the financial costs of managing persons with epilepsy (PWE) have not been assessed in these settings. Proper cost analyses will facilitate future health interventions. MethodsIn November 2017, persons with epilepsy (PWE) and their caretakers were recruited at health centres of the Logo health zone in the Democratic Republic of Congo. A pre-tested questionnaire was administered to collect information on both direct and indirect costs of epilepsy, as well as household income of participants. FindingsThe weighted mean cost of epilepsy was 241.2 USD per PWE per year (50.2% direct cost, 49.8% indirect cost). Epilepsy-related expenses represented 46.5% of the mean household income. Traditional medicine accounted for 68.2% of the direct cost. An estimated cumulative cost of 1929.6 USD attributable to epilepsy had been incurred by the populations of the Logo health zone for each PWE in the community. InterpretationAlmost half of the household revenue was spent on epilepsy care. Expenses on traditional medicine must be discouraged via education and regular provision of affordable anti-epileptic drugs. Prevention of onchocerciasis-associated epilepsy using optimal control measures will avert additional epilepsy-related costs on the community. Early diagnosis and proper management of epilepsy would be economically beneficial in the study villages.

Clinical presentations of onchocerciasis-associated epilepsy (OAE) in Cameroon

BackgroundA high prevalence of epilepsy has been observed in several onchocerciasis-endemic countries, including Cameroon. However, little is known on the clinical presentations of the affected persons with epilepsy (PWE). A community-based study was conducted with the aim of describing the spectrum of seizures in selected onchocerciasis-endemic villages in Cameroon and documenting relevant medical history in patients with onchocerciasis-associated epilepsy (OAE). MethodsWe carried out door-to-door surveys in 5 onchocerciasis-endemic villages in Cameroon and recruited all consenting PWE. Epilepsy was diagnosed using a 2-step approach consisting of the administration of a standardized 5-item questionnaire followed by confirmation of the suspected cases by a neurologist. Onchocerciasis-associated epilepsy was defined as ≥2 seizures without an obvious cause, starting between the ages of 3–18 years in previously healthy persons having resided for at least 3 years in an onchocerciasis-endemic area. Ivermectin use by PWE was verified. Seizure history, relevant past medical, and family history, as well as neurological findings, were noted. ResultsIn all, 156 PWE were recruited in the 5 villages. The modal age group for epilepsy onset was 10–14 years. The diagnostic criteria for OAE were met by 93.2% of the PWE. Participants had one or more of the following seizure types: generalized tonic–clonic seizures (89.1%), absences (38.5%), nodding (21.8%), focal nonmotor (7.7%), and focal motor seizures (1.9%). One case (0.6%) with the “Nakalanga syndrome” was identified. More than half (56.4%) of PWE had at least one seizure per month. In one village, 56.2% of PWE had onchocercal skin lesions. ConclusionPeople with epilepsy in onchocerciasis-endemic villages in Cameroon present with a wide clinical spectrum including nodding seizures and Nakalanga features. A great majority of participants met the diagnostic criteria for OAE, suggesting that better onchocerciasis control could prevent new cases. Epilepsy management algorithms in these areas must be adjusted to reflect the varied seizure types.

Epidemiology of onchocerciasis-associated epilepsy in the Mbam and Sanaga river valleys of Cameroon: impact of more than 13\xa0years of ivermectin

BackgroundA high epilepsy prevalence has been reported in several onchocerciasis-endemic villages along the Mbam and Sanaga river valleys in Cameroon, including Bilomo and Kelleng. We sought to determine the prevalence of epilepsy in these two villages following more than 13 years of community-directed treatment with ivermectin (CDTI).MethodsDoor-to-door surveys were performed on the entire resident population in the villages in August 2017 and January 2018. Epilepsy was diagnosed using a 2-step approach: administration of a standardized 5-item questionnaire followed by confirmation by a neurologist. Previously published diagnostic criteria for onchocerciasis-associated epilepsy (OAE) were used. Ov16 serology was done for children aged 7–10 years to assess onchocerciasis transmission. Findings were compared with previous data from these two villages.ResultsA total of 1525 individuals (1321 in Bilomo and 204 in Kelleng) in 233 households were surveyed in both villages. The crude prevalence of epilepsy was 4.6% in Bilomo (2017) and 7.8% in Kelleng (2018), including 12 (15.6% of cases) persons with epilepsy (PWE) with nodding seizures. The age and sex-standardized prevalence in Kelleng decreased from 13.5% in 2004 to 9.3% in 2018 (P < 0.001). The median age of PWE shifted from 17 (IQR: 12–22) years to 24 (IQR: 20–30) years in Bilomo (P < 0.001); and slightly from 24 (IQR: 14–34) years to 28 (IQR: 21.25–36.75) years in Kelleng (P = 0.112). Furthermore, 47.6% of all tested children between 7 and 10 years had Ov16 antibodies.ConclusionsThere is a decrease in epilepsy prevalence after 13 years and more of CDTI in both villages. The age-shift observed in PWE suggests that ivermectin may prevent OAE in younger residents. Ov16 seropositivity in children indicates ongoing onchocerciasis transmission possibly due to suboptimal control measures. Our findings support the existence of OAE in Cameroon and highlight the need to strengthen onchocerciasis elimination programs.

The effect of bi-annual community-directed treatment with ivermectin on the incidence of epilepsy in onchocerciasis endemic villages in South Sudan: a study protocol

BackgroundNodding syndrome (NS) is a devastating epileptic illness of unknown aetiology mainly affecting children 5–15 years of age. Head nodding distinguishes NS from other forms of epilepsy. Other manifestations of the illness include mental and physical growth retardation. Many children die as a result of falling in fires or drowning. Recently, it was shown that NS is only one of the phenotypic presentations of onchocerciasis associated epilepsy (OAE). Despite the strong epidemiological association between epilepsy and onchocerciasis, the causal mechanism is unknown. After implementation of bi-annual community directed treatment with ivermectin (CDTi) and larviciding of rivers in northern Uganda, new cases of NS have ceased, while new cases continue to emerge in South Sudanese onchocerciasis-endemic areas with an interrupted CDTi programme. This study is designed to evaluate the potential effects of bi-annual CDTi on reducing the incidence of NS/OAE in onchocerciasis-endemic areas in South Sudan.MethodsA pre-intervention door-to-door population-based household survey will be conducted in selected onchocerciasis-endemic villages in Mundri and Maridi Counties, which have a high prevalence of epilepsy. Using a validated questionnaire, the entire village will be screened by community research assistants for suspected epilepsy cases. Suspected cases will be interviewed and examined by a trained clinical officer or medical doctor who will confirm or reject the diagnosis of epilepsy. Bi-annual CDTi will be implemented in the villages and a surveillance system for epilepsy set up. By implementing an epilepsy onchocerciasis awareness campaign we expect to obtain > 90% CDTi coverage of eligible individuals. The door-to-door survey will be repeated two years after the baseline survey. The incidence of NS/OAE will be compared before and after bi-annual CDTi.DiscussionOur study is the first population-based study to evaluate the effect of bi-annual CDTi to reduce the incidence of NS/OAE. If the study demonstrates such a reduction, these findings are expected to motivate communities in onchocerciasis-endemic regions to participate in CDTi, and will encourage policy makers, funders and other stakeholders to increase their efforts to eliminate onchocerciasis.

Clinical characteristics of onchocerciasis-associated epilepsy in villages in Maridi County, Republic of South Sudan

PurposeTo describe the clinical manifestations of persons with epilepsy (PWE) in onchocerciasis endemic villages in South Sudan. MethodsDuring a survey in Maridi County in May 2018, PWE were interviewed and examined in their households by a clinical officer or medical doctor. Onchocerciasis-associated epilepsy (OAE) was defined as ≥2 seizures without any obvious cause, starting between the ages of 3–18 years in previously healthy persons who had resided for at least 3 years in the onchocerciasis endemic area. ResultsSeven hundred and thirty-six PWE were included in the study; 315 (42.8%) were females; median age was 18 years. A variety of seizure types were reported: generalized tonic-clonic seizures in 511 PWE (69.4%), absences in 15 (2.0%), focal motor seizures with full awareness in 7 (1.0%), focal motor seizures with impaired awareness in 25 (3.4%), brief episodes of hallucinations in 316 (43.9%) and nodding seizures in 335 (45.5%). The median age of onset of all seizures was 10 years, and 8 years for nodding seizures. PWE with nodding seizures presented with more cognitive disabilities. The diagnostic criteria for OAE were met by 414 (85.2%) of the 486 PWE with complete information. Eighty (11.0%) PWE presented with Nakalanga features. Only 378 (51.4%) PWE were taking anti-epileptic treatment. ConclusionPWE presented with a wide spectrum of seizures. The high percentage of PWE who met the diagnostic criteria for OAE suggests that better onchocerciasis control could prevent new cases. Urgent action is needed to close the anti-epileptic treatment gap.

Onchocerciasis-Associated Epilepsy in Children and Adolescents in Africa: A Multi-Country Community-Based Study

Background: Epilepsy is a leading cause of morbidity and mortality in sub-Saharan Africa. A high epilepsy prevalence has been reported in onchocerciasis-endemic regions, where seizure onset commonly occurs during childhood or early adolescence. We investigated epilepsy in individuals aged 5-19 years living in onchocerciasis-endemic regions. Methods: Between 2016 and 2018, household epilepsy surveys were performed in onchocerciasis-endemic villages in Cameroon, Democratic Republic of Congo, Nigeria, South Sudan, Tanzania, and Uganda. Using a validated questionnaire, all households were screened for children and adolescents suspected to have epilepsy. The latter were further examined by a trained clinical officer, medical doctor and/or neurologist for confirmation. Onchocerciasis-associated epilepsy (OAE) was defined as epilepsy starting between the ages of 3-18 years in previously healthy children living in onchocerciasis meso- or hyper-endemic areas, with no other known cause of seizures. Findings: Of the 13 000 children and adolescents aged 5-19 years who were screened, 676 (5·2%) had epilepsy; of those, 450 (66·6%) met all OAE diagnostic criteria. Eighty percent of individuals with epilepsy had seizures monthly, 25·7% showed cognitive abnormalities, and 9·8% had burns or traumatic lesions related to seizures. Only 53·6% of participants with epilepsy received daily anti-epileptic treatment, and 62·1% had not completed primary education by the age of 13 years. Excess mortality among subjects with epilepsy ranged from 26 to 69 per 1000 individuals aged 5-19 years. Epilepsy annual incidence was 6·1 per 1000 individuals, and was lowest in areas with low onchocerciasis transmission. Interpretation: OAE causes considerable morbidity and mortality among individuals aged 5-19 years and affects their health, education and quality of life. Urgent action is needed to prevent children from developing OAE, and to provide treatment and care for all children and adolescents with epilepsy in onchocerciasis-endemic regions. Funding Statement: ERC Advanced Grant (67105), NSETHIO Project. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: Ethical approval was obtained for all studies from the ethics committee of the University of Antwerp, Belgium and from the ethics committees in the African countries. The study aims and procedures were explained to all participants in the language of their choice and signed or finger-printed informed consent was obtained from participants, parents or caretakers, and assent from adolescents (age 12–19 years). All personal information was encoded and treated confidentially.

Testing Alternative Record Keeping Formats Not Requiring Literacy Skills: Onchocerciasis Control at the Village Level

Keeping accurate health records at the village level is a challenge since many rural dwellers have low or no literacy skills. The African Programme for Onchocerciasis Control (APOC) is distributing the drug ivermectin at the village level by villagers themselves, and requires an accounting of drugs dispensed and villagers treated. Recently, pictorial tally sheets were developed for Community Directed Distributors (CDDs) of ivermectin. At that same time a question arose concerning indigenous record keeping methods and whether such methods could also be adapted to ivermectin distribution. This study identified two indigenous methods, counting beans/pebbles and chalk/charcoal marks on walls and compared them with the pictorial tally sheets in three clusters of onchocerciasis-endemic villages in Kajola Local Government Area (LGA) of Oyo State, Nigeria. Field staff trained the CDDs using standard APOC procedures and after distribution, collected their treatment records. A household survey was then conducted for comparison with CDD records. The tally sheet users scored the lowest mean and median percentage point difference between reported and surveyed coverage (6.6 and 4.8) compared to chalk boards (19.0, 5.6) and pebbles (15.2, 9.2), but since the village was the unit of analysis, the differences observed were of only boarderline significance ( p = 0.08). Because the tally sheets proved to be both cheaper and easier to use, they are recommended for community ivermectin programs as well as other primary health care activities at the village level.