03655nas a2200325   4500000000100000008004100001260001600042653002100058653001900079653002500098653002500123653001300148100001200161700001300173700001200186700001400198700001500212700001100227700001400238700001600252700001400268700001400282700001800296245016200314856007500476300001600551490000700567520274100574022001403315       2023                            d  bElsevier BV10aGeneral Medicine10aonchocerciasis10aLongitudinal studies10aelimination measures10aEpilepsy1 aJada SR1 aAmaral L1 aLakwo T1 aCarter JY1 aRovarini J1 aBol YY1 aLogora MY1 aHadermann A1 aHopkins A1 aFodjo JNS1 aColebunders R00aEffect of onchocerciasis elimination measures on the incidence of epilepsy in Maridi, South Sudan: a 3-year longitudinal, prospective, population-based study  uhttps://www.thelancet.com/action/showPdf?pii=S2214-109X%2823%2900248-6  ae1260-e12680 v113 a<p><strong>Background:</strong> 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.</p>

<p><strong>Methods:</strong> 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.</p>

<p><strong>Findings:</strong> The preintervention survey included 17 652 people of whom 736 had epilepsy (315 female and 421 male), and the post-intervention survey included 14402 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 100000 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.</p>

<p><strong>Interpretation:</strong> 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.</p>
  a2214-109X