In June 2020, a door-to-door household survey was conducted in Mvolo County, an onchocerciasis-endemic area in South Sudan. A total of 2357 households containing 15,699 individuals agreed to participate in the study. Of these, 5046 (32.1%, 95% CI: 31.4-32.9%) had skin itching and 445 (2.8%, 95% CI: 2.6-3.1%) were blind. An epilepsy screening questionnaire identified 813 (5.1%) persons suspected of having epilepsy. Of them, 804 (98.9%) were seen by a medical doctor, and in 798 (98.1%) the diagnosis of epilepsy was confirmed. The overall epilepsy prevalence was 50.8/1000 (95% CI: 47.6-54.4/1000), while the prevalence of nodding syndrome was 22.4/1000 (95% CI: 20.1-24.9/1000). Younger age, being male, skin itching, blindness, and living in a neighbourhood or village close to the Naam River were risk factors for epilepsy. The annual incidence of epilepsy was 82.8/100,000 (95% CI: 44.1-141.6/100,000). Among children 7-9 years old without epilepsy, 34% were Ov16 seropositive, suggesting high ongoing Onchocerca volvulus transmission, but only 41.9% of them took ivermectin during the last mass distribution. In conclusion, a high prevalence and incidence of epilepsy was observed in Mvolo, South Sudan. Strengthening of the onchocerciasis elimination programme is urgently needed in order to prevent epilepsy in this region.
Raimon S, Dusabimana A, Abd-Elfarag G, Okaro S, Carter JY, Newton CR, Logora MY, Colebunders R.