Decreasing epilepsy-related mortality in the Maridi onchocerciasis focus, South Sudan

Introduction

A 2018 study found high epilepsy prevalence and mortality in the Maridi onchocerciasis focus (South Sudan). From 2019 onward, onchocerciasis elimination measures were strengthened in Maridi, and in 2020, an epilepsy clinic was established at Maridi County Hospital with free provision of anti-seizure medication. We investigated the changes in epilepsy-related mortality following these interventions.

Methods

Repeated house-to-house surveys (2018 and 2024) in three Maridi neighbourhoods (Kazana-1, Kazana-2, Hai-Gabat). The number of deaths that occurred during the two years preceding each survey among persons known to have epilepsy (PWE) was assessed in each home via verbal reports from the household head. Mortality rates were calculated and compared between surveys using the rate-ratio test.

Results

Between 2018 and 2024, epilepsy mortality in Maridi decreased 4.2-fold from 78.3 to 18.7 per 1000 person-years (p<0.001). The decrease in mortality was most evident among the 11-20 year-olds: 6.9-fold reduction from 66.9 to 9.7 per 1000 person-years (p=0.001). Age-standardized mortality ratio of epilepsy was estimated at 1.8 in 2024. Among the 184 reported deaths during the 2022-2024 observation period, the proportion of deceased PWE reduced from 9.7% (2022) to 4.5% (2023) to 1.8% (2024), although without statistical significance (p=0.175).

Conclusion

Strengthening onchocerciasis elimination measures and establishing an epilepsy clinic were followed by a drastic decrease in PWE mortality rate in Maridi. By preventing new-onset onchocerciasis-associated epilepsy and treating PWE with free anti-seizure medication, this two-pronged approach could mitigate the high premature mortality observed among PWE, especially adolescents. This strategy may be applicable to other onchocerciasis hotspots with high epilepsy burden.