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. In areas where many people have onchocerciasis, a parasitic infection spread by female blackflies, there is often a high occurrence of epilepsy. The latter includes nodding syndrome (NS), a type of epilepsy where the head repeatedly drops forward. This is the case in Mvolo County, South Sudan. Our study examined how the annual intake of ivermectin, a drug that prevents onchocerciasis, impacted the occurrence of new epilepsy cases, including NS, in the county. In June 2020, we visited selected sites and screened 15,480 individuals for epilepsy, with confirmation of diagnosis by a medical professional. This exercise was repeated in June 2022 with 15,092 individuals. We found fewer new epilepsy and probable NS cases after introducing annual ivermectin treatment. Still, not all eligible community members received the treatment, with 64% of participants reporting taking ivermectin in 2019 and only 24% in 2021. Our research further corroborates that ivermectin intake at the community level can help reduce the high number of epilepsy and NS cases in regions where onchocerciasis is found. Consequently, it is imperative that individuals at risk for onchocerciasis, particularly those within the 5-18-year-old age group, who are most susceptible to developing onchocerciasis-associated epilepsy, have access to annual ivermectin.
Source (journal)
PLoS neglected tropical diseases
18 :3 (2024) , p. 1-23
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Nodding Syndrome: a trans-disciplinary approach to identify the cause and decrease the incidence of river epilepsy (NSETHIO).
Reducing onchocerciasis-associated morbidity in children.
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Publications with a UAntwerp address
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Web of Science
Creation 02.05.2024
Last edited 08.05.2024
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