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

Abstract

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.