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Siewe Fodjo JN, Jada SR, Taban A, Bebe J, Yak Bol Y, Carter JY, Colebunders R. Epidemiology of epilepsy in Wulu County, an onchocerciasis-endemic area in South Sudan. Heliyon 2024; 10:e37537. [PMID: 39309807 PMCID: PMC11415701 DOI: 10.1016/j.heliyon.2024.e37537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 08/13/2024] [Accepted: 09/04/2024] [Indexed: 09/25/2024] Open
Abstract
Background We sought to investigate the epidemiology of epilepsy in Wulu County (Lakes State, South Sudan), and document the onchocerciasis transmission status in the study villages. Methods In February 2024, a community-based epilepsy study was conducted Wulu County and participants were surveyed via a door-to-door approach in five villages, namely: Kombi, Makundi Center, Tonjo, War-Pac, and Woko. All village residents were asked about ivermectin intake during the 2023 round of community-directed treatment with ivermectin (CDTI). In addition, children aged 3-9 years were tested for Ov16 antibodies using a rapid diagnostic test. Epilepsy diagnosis in screened individuals was confirmed by a physician. Results We surveyed 1355 persons in the five study sites. The overall CDTI coverage in 2023 was 67.4 %. Fifty-five persons with epilepsy (PWE) were identified (prevalence 4.1 %) and a history of nodding seizures was noted in 11/55 (20 %) PWE. The mean age of PWE was 21.5 ± 9.6 years, with 32 (58.2 %) being males. Epilepsy onset frequently occurred under 5 years of age (38.6 % of cases). In two PWE, seizure onset occurred during the past 12 months (annual incidence: 147.6 per 100,000 persons). Twenty-nine PWE (52.7 %) were taking anti-seizure medicines, but only five were taking them daily. Overall, Ov16 seroprevalence in children aged 3-9 years (n = 119) was 15.1 % and differed across villages, peaking at 30.9 % in Woko village where epilepsy prevalence was also highest (7.1 %). Of the 35 recorded deaths during the past two years, 9 (25.7 %) occurred in PWE. Annual estimates for epilepsy mortality and fatality rates were 323.7 per 100,000 persons and 7031.3 per 100,000 PWE, respectively. Conclusion High epilepsy prevalence was found in Wulu, particularly in villages with persistent onchocerciasis transmission. Frequent epilepsy onset among under-fives suggests that perinatal/early childhood etiologies are common. Appropriate measures should be instituted to prevent and treat epilepsy in Wulu villages.
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Affiliation(s)
| | | | - Abraham Taban
- Wulu County Neglected Tropical Diseases Unit, South Sudan
| | - John Bebe
- Amref Health Africa, Juba, South Sudan
| | - Yak Yak Bol
- Neglected Tropical Diseases Unit, Ministry of Health, Juba, South Sudan
| | | | - Robert Colebunders
- Global Health Institute, University of Antwerp, Antwerp, Belgium
- Department of Tropical Disease Biology, Liverpool School of Tropical Diseases, Liverpool, United Kingdom
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Quek S, Hadermann A, Wu Y, De Coninck L, Hegde S, Boucher JR, Cresswell J, Foreman E, Steven A, LaCourse EJ, Ward SA, Wanji S, Hughes GL, Patterson EI, Wagstaff SC, Turner JD, Parry RH, Kohl A, Heinz E, Otabil KB, Matthijnssens J, Colebunders R, Taylor MJ. Diverse RNA viruses of parasitic nematodes can elicit antibody responses in vertebrate hosts. Nat Microbiol 2024:10.1038/s41564-024-01796-6. [PMID: 39232205 DOI: 10.1038/s41564-024-01796-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 07/25/2024] [Indexed: 09/06/2024]
Abstract
Parasitic nematodes have an intimate, chronic and lifelong exposure to vertebrate tissues. Here we mined 41 published parasitic nematode transcriptomes from vertebrate hosts and identified 91 RNA viruses across 13 virus orders from 24 families in ~70% (28 out of 41) of parasitic nematode species, which include only 5 previously reported viruses. We observe widespread distribution of virus-nematode associations across multiple continents, suggesting an ancestral acquisition event and host-virus co-evolution. Characterization of viruses of Brugia malayi (BMRV1) and Onchocerca volvulus (OVRV1) shows that these viruses are abundant in reproductive tissues of adult parasites. Importantly, the presence of BMRV1 RNA in B. malayi parasites mounts an RNA interference response against BMRV1 suggesting active viral replication. Finally, BMRV1 and OVRV1 were found to elicit antibody responses in serum samples from infected jirds and infected or exposed humans, indicating direct exposure to the immune system.
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Affiliation(s)
- Shannon Quek
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Amber Hadermann
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Yang Wu
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Lander De Coninck
- Laboratory of Viral Metagenomics, Clinical and Epidemiological Virology, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Shrilakshmi Hegde
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Jordan R Boucher
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Jessica Cresswell
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Ella Foreman
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Andrew Steven
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - E James LaCourse
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Stephen A Ward
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Samuel Wanji
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Grant L Hughes
- Centre for Neglected Tropical Diseases, Departments of Tropical Disease Biology and Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Edward I Patterson
- Department of Biological Sciences, Brock University, St Catharines, Ontario, Canada
| | - Simon C Wagstaff
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Joseph D Turner
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Rhys H Parry
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Alain Kohl
- Centre for Neglected Tropical Diseases, Departments of Tropical Disease Biology and Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Eva Heinz
- Departments of Vector Biology and Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Kenneth Bentum Otabil
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Sciences, University of Energy and Natural Resources, Sunyani, Ghana
| | - Jelle Matthijnssens
- Laboratory of Viral Metagenomics, Clinical and Epidemiological Virology, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | | | - Mark J Taylor
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
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Pierella E, Siewe Fodjo JN, Colebunders R. Doxycycline, a role in the treatment of onchocerciasis-associated epilepsy? Trends Parasitol 2024; 40:667-669. [PMID: 39060121 DOI: 10.1016/j.pt.2024.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2024] [Accepted: 06/10/2024] [Indexed: 07/28/2024]
Abstract
Can the antibiotic doxycycline unlock new possibilities in the fight against onchocerciasis-associated epilepsy (OAE)? Idro et al. explored this question by investigating for the first time doxycycline's impact on nodding syndrome (NS), a severe manifestation of OAE. Results reveal significant findings that may shape future treatment strategies.
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Affiliation(s)
- Elisa Pierella
- School of Medicine and Dentistry, University of Central Lancashire, Preston, UK
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4
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Idro R, Ogwang R, Anguzu R, Akun P, Ningwa A, Abbo C, Giannoccaro MP, Kubofcik J, Mwaka AD, Nakamya P, Opar B, Taylor M, Nutman TB, Elliott A, Vincent A, Newton CR, Marsh K. Doxycycline for the treatment of nodding syndrome: a randomised, placebo-controlled, phase 2 trial. Lancet Glob Health 2024; 12:e1149-e1158. [PMID: 38754459 PMCID: PMC11191365 DOI: 10.1016/s2214-109x(24)00102-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 02/15/2024] [Accepted: 03/04/2024] [Indexed: 05/18/2024]
Abstract
BACKGROUND Nodding syndrome is a poorly understood neurological disorder that predominantly occurs in Africa. We hypothesised that nodding syndrome is a neuroinflammatory disorder, induced by antibodies to Onchocerca volvulus or its Wolbachia symbiont, cross-reacting with host neuronal proteins (HNPs), and that doxycycline can be used as treatment. METHODS In this randomised, double-blind, placebo-controlled, phase 2 trial, we recruited participants from districts affected by nodding syndrome in northern Uganda. We included children and adolescents aged 8-18 years with nodding syndrome, as defined by WHO consensus criteria. Participants were randomly assigned (1:1) to receive either 100 mg doxycycline daily or placebo for 6 weeks via a computer-generated schedule stratified by skin microscopy results, and all parties were masked to group assignment. Diagnoses of O volvulus and antibodies to HNPs were made using luciferase immunoprecipitation system assays and immunohistochemistry. The primary outcome was change in the proportion with antibodies to HNPs, assessed at 24 months. All participants were included in safety analyses, and surviving participants (those with samples at 24 months) were included in primary analyses. Secondary outcomes were: change in concentrations of antibodies to HNPs at 24 months compared with baseline; proportion of participants testing positive for antibodies to O volvulus-specific proteins and concentrations of Ov16 or OVOC3261 antibodies at 24 months compared with baseline; change in seizure burden, proportion achieving seizure freedom, and the proportions with interictal epileptiform discharges on the diagnostic EEG; overall quality of life; disease severity at 24 months; and incidence of all-cause adverse events, serious adverse events, and seizure-related mortality by 24 months. This trial is registered with ClinicalTrials.gov, NCT02850913. FINDINGS Between Sept 1, 2016, and Aug 31, 2018, 329 children and adolescents were screened, of whom 240 were included in the study. 140 (58%) participants were boys and 100 (42%) were girls. 120 (50%) participants were allocated to receive doxycycline and 120 (50%) to receive placebo. At recruitment, the median duration of symptoms was 9 years (IQR 6-10); 232 (97%) participants had O volvulus-specific antibodies and 157 (65%) had autoantibodies to HNPs. The most common plasma autoantibodies were to human protein deglycase DJ-1 (85 [35%] participants) and leiomodin-1 (77 [32%] participants) and, in cerebrospinal fluid (CSF), to human DJ-1 (27 [11%] participants) and leiomodin-1 (14 [6%] participants). On immunohistochemistry, 46 (19%) participants had CSF autoantibodies to HNPs, including leiomodin-1 (26 [11%]), γ-aminobutyric acid B receptors (two [<1%]), CASPR2 (one [<1%]), or unknown targets (28 [12%]). At 24 months, 161 (72%) of 225 participants had antibodies to HNPs compared with 157 (65%) of 240 at baseline. 6 weeks of doxycycline did not affect the concentration of autoantibodies to HNPs, seizure control, disease severity, or quality of life at the 24-month follow-up but substantially decreased Ov16 antibody concentrations; the median plasma signal-to-noise Ov16 ratio was 16·4 (95% CI 6·4-38·4), compared with 27·9 (8·2-65·8; p=0·033) for placebo. 14 (6%) participants died and, other than one traffic death, all deaths were seizure-related. Acute seizure-related hospitalisations (rate ratio [RR] 0·43 [95% CI 0·20-0·94], p=0·028) and deaths (RR 0·46 [0·24-0·89], p=0·028) were significantly lower in the doxycycline group. At 24 months, 96 (84%) of 114 participants who received doxycycline tested positive for antibodies to Ov16, compared with 97 (87%) of 111 on placebo (p=0·50), and 74 (65%) participants on doxycycline tested positive for antibodies to OVOC3261, compared with 57 (51%) on placebo (p=0·039). Doxycycline was safe; there was no difference in the incidence of grade 3-5 adverse events across the two groups. INTERPRETATION Nodding syndrome is strongly associated with O volvulus and the pathogenesis is probably mediated through an O volvulus induced autoantibody response to multiple proteins. Although it did not reverse disease symptoms, doxycycline or another prophylactic antibiotic could be considered as adjunct therapy to antiseizure medication, as it might reduce fatal complications from acute seizures and status epilepticus induced by febrile infections. FUNDING Medical Research Council (UK). TRANSLATION For the Luo translation of the abstract see Supplementary Materials section.
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Affiliation(s)
- Richard Idro
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda; Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK.
| | - Rodney Ogwang
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Ronald Anguzu
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Pamela Akun
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Albert Ningwa
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Catherine Abbo
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Maria P Giannoccaro
- Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Italy
| | - Joseph Kubofcik
- Laboratory of Parasitic Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Amos D Mwaka
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | | | - Mark Taylor
- Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Thomas B Nutman
- Laboratory of Parasitic Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alison Elliott
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene & Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Charles R Newton
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, UK
| | - Kevin Marsh
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
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Lakwo TL, Alinda P, Jada SR, Tionga M, Marcello CDR, War DGD, Colebunders R. Mvolo County, an Onchocerciasis Endemic Area in Western Equatoria State, South Sudan: An Entomological Study to Prepare for a "Slash and Clear" Community-Based Vector Control Intervention. Res Rep Trop Med 2024; 15:59-71. [PMID: 38895129 PMCID: PMC11184223 DOI: 10.2147/rrtm.s464874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/17/2024] [Indexed: 06/21/2024] Open
Abstract
Background Mvolo in Western Equatoria of South Sudan has been a hotspot for Onchocerca volvulus transmission since the 1940s. In Mvolo onchocerciasis is a disease of public health importance, associated with onchocerciasis-associated epilepsy including nodding syndrome. Methods We conducted an entomological study to map the breeding sites of blackflies (Simulium damnosum, sensu lato) on the river Naam, to allow the removal of vegetation from vector breeding sites, the "slash and clear". Three blackfly catching sites were established along the river. Focus group discussions were also conducted to assess the willingness of the communities to support the "slash and clear" intervention and the semi-annual distribution of ivermectin. Results A total of 2466 female S. damnosum s.l. were caught in 14×11h (06.00-15.00) catches. The highest biting density of 4210.25 flies/month/h and monthly biting rate (MBR) of 11,482.25 bites/man/month were observed in November 2023. Biting density and MBR reduced to zero in the intervention site by April 2024. While the mean parity rate was 31% (CI: 0.2976±0.9176). Two diurnal biting peaks were observed, one from 9:00-10:00 (at the bridge site) and a prominent one from 14:00-15:00 in the two catching sites in Mvolo. Along the river Naam, only one site was found productive for S. damnosum s.l.; and the larvae and adults were morphologically associated with the anthropophilic S. damnosum. The "slash and clear" intervention was implemented at Dogoyabolu along the river Naam. Communities expressed willingness to support a "slash and clear" intervention and the semi-annual distribution of ivermectin. Conclusion S. damnosum active breeding was identified along the river Naam in a stretch of 3-5 km close to human settlements. Highest blackfly biting density was 4210.25 flies/month/h, and two fly biting peaks were observed. A community "slash and clear" vector control was implemented, and will be prospectively monitored.
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Affiliation(s)
| | - Peter Alinda
- Ministry of Health, Vector Control Division, Kampala, Uganda
| | | | | | | | - Deng Gai Dual War
- Ministry of Health, National Malaria Control Program, Juba, South Sudan
| | - Robert Colebunders
- Global Health Institute, University of Antwerp, Antwerp, Belgium
- Department of Tropical Disease Pathology, Liverpool School of Tropical Medicine, Liverpool, UK
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Kamoen O, Jada SR, Rovarini JM, Abd-Elfarag G, Amaral LJ, Bol Y, Siewe Fodjo JN, Colebunders R. Evaluating epilepsy management in an onchocerciasis-endemic area: Case of Maridi, South Sudan. Seizure 2024:S1059-1311(24)00133-X. [PMID: 38714396 DOI: 10.1016/j.seizure.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 04/30/2024] [Accepted: 05/01/2024] [Indexed: 05/09/2024] Open
Abstract
PURPOSE The epilepsy prevalence in Maridi County, South Sudan, in 2018 was 43.8 (95% CI: 40.9-47.0) per 1000 persons; 85.2% of the identified persons with epilepsy (PWE) met the criteria of onchocerciasis-associated epilepsy. To address this health problem, an epilepsy clinic was established at Maridi County Hospital in 2020. In August 2023, the impact of the clinic on the lives of PWE and their families was evaluated. METHODS At the Maridi epilepsy clinic, data routinely collected by primary healthcare workers as part of patient care was reviewed. We also analyzed findings from two household surveys conducted in 2018 and 2022, which assessed the impact of the clinic on epilepsy care. Moreover, four households, each with four PWE, were visited in a high epilepsy prevalence area. PWE were examined by a neurologist, and in-depth interviews were conducted with family members. RESULTS The proportion of PWE on anti-seizure medication increased by 39.7% (95%CI: 35.3-44.2) between 2018 and 2022. The proportion of PWE reporting daily seizures decreased from 27.3% in 2018 to 5.3% in 2022. Of the 754 PWE seen in the clinic in July 2023, only 17 (2.3%) reported side effects. During household visits in July 2023, 13/173 (7.5%) of the visited PWE were found without remaining anti-seizure medication. A high level of epilepsy-related stigma was observed in all visited households. CONCLUSION The Maridi epilepsy clinic positively impacted the lives of PWE in Maridi. Similar initiatives should be accessible for all PWE living in onchocerciasis-endemic areas. Evidence-based information about OAE is needed to decrease misconceptions and epilepsy-related stigma.
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Affiliation(s)
- Olivia Kamoen
- Department of Neurology, Heilig Hart Ziekenhuis, Lier, Belgium
| | | | | | - Gasim Abd-Elfarag
- Access for Humanity, Juba, South Sudan; School of Public Health, University of Juba, Juba, South Sudan; Health and Social Sciences Research Institute-South Sudan, Juba, South Sudan
| | | | - Yak Bol
- Neglected Tropical Disease Programme, Ministry of Health, Juba, South Sudan
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Colebunders R, Hadermann A, Njamnshi AK, Mmbando BP, Kamoen O, Siewe Fodjo JN. Onchocerciasis-associated epilepsy and biomarkers. PLoS Negl Trop Dis 2024; 18:e0011808. [PMID: 38722830 PMCID: PMC11081238 DOI: 10.1371/journal.pntd.0011808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 11/20/2023] [Indexed: 05/13/2024] Open
Affiliation(s)
| | - Amber Hadermann
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Alfred K. Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
- Neuroscience Lab, Faculty of Medicine & Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
| | - Bruno P. Mmbando
- National Institute for medical Research, Tanga Research Centre, Tanga, Tanzania
| | - Olivia Kamoen
- Department of Neurology, Heilig Hart Ziekenhuis, Lier, Belgium
| | - Joseph Nelson Siewe Fodjo
- Global Health Institute, University of Antwerp, Antwerp, Belgium
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
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Van Cutsem G, Siewe Fodjo JN, Hadermann A, Amaral LJ, Trevisan C, Pion S, Colebunders R. Onchocerciasis-associated epilepsy: Charting a path forward. Seizure 2024:S1059-1311(24)00123-7. [PMID: 38677953 DOI: 10.1016/j.seizure.2024.04.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 04/29/2024] Open
Abstract
This narrative review intends to inform neurologists and public health professionals about Onchocerciasis-Associated Epilepsy (OAE), a neglected public health problem in many remote onchocerciasis-endemic areas. For epidemiological purposes, we define OAE as sudden-onset of convulsive and non-convulsive seizure types, including head nodding seizures (nodding syndrome) in a previously healthy child aged 3 to 18 years in the absence of any other obvious cause for epilepsy, all happening within an area with high ongoing Onchocerca volvulus transmission. Several OAE pathophysiological mechanisms have been proposed, but none has been proven yet. Recent population-based studies showed that strengthening onchocerciasis elimination programs was followed by a significant reduction in the incidence of OAE and nodding syndrome. Treating epilepsy in onchocerciasis-endemic regions is challenging. More advocacy is needed to provide uninterrupted, free access to anti-seizure medication to persons with epilepsy in these remote, impoverished areas. It is crucial todevelop policies and increase funding for the prevention and treatment of OAE to reduce the associated burden of disease, notably via the establishment of morbidity management and disability prevention programs (MMDP). Moreover, effective collaboration between onchocerciasis elimination and mental health programs is imperative to alleviate the burden of OAE. This synergy promises reciprocal advantages and underscores the need for a comprehensive approach to address this multifaceted challenge.
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Affiliation(s)
- G Van Cutsem
- Department of Neurology, Centre Hospitalier de Luxembourg, Luxembourg; Faculty of Science, Technology and Medicine, University of Luxembourg, Luxembourg; Centre for Infectious Disease Epidemiology and Research, University of Cape Town, South Africa
| | - J N Siewe Fodjo
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - A Hadermann
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - L-J Amaral
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - C Trevisan
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - S Pion
- Institute of Research for Sustainable Development, Montpelier, France
| | - R Colebunders
- Global Health Institute, University of Antwerp, Antwerp, Belgium.
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Amaral LJ, Jada SR, Ndjanfa AK, Carter JY, Abd-Elfarag G, Okaro S, Logora MY, Bol YY, Lakwo T, Fodjo JNS, Colebunders R. Impact of annual community-directed treatment with ivermectin on the incidence of epilepsy in Mvolo, a two-year prospective study. PLoS Negl Trop Dis 2024; 18:e0012059. [PMID: 38512994 PMCID: PMC10986994 DOI: 10.1371/journal.pntd.0012059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/02/2024] [Accepted: 03/08/2024] [Indexed: 03/23/2024] Open
Abstract
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.
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Affiliation(s)
| | | | | | | | - Gasim Abd-Elfarag
- Amref Health Africa, South Sudan
- Access for Humanity, Juba, South Sudan
- School of Public Health, University of Juba, Juba, South Sudan
| | | | - Makoy Yibi Logora
- Neglected Tropical Diseases Unit, Ministry of Health, Juba, South Sudan
| | - Yak Yak Bol
- Neglected Tropical Diseases Unit, Ministry of Health, Juba, South Sudan
| | - Thomson Lakwo
- Vector Control Division, Ministry of Health, Kampala, Uganda
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Colebunders R, Siewe Fodjo JN, Kamoen O, Amaral LJ, Hadermann A, Trevisan C, Taylor MJ, Gauglitz J, Hoerauf A, Sato Y, Polman K, Basáñez MG, Bhwana D, Lakwo T, Abd-Elfarag G, Pion SD. Treatment and prevention of epilepsy in onchocerciasis-endemic areas is urgently needed. Infect Dis Poverty 2024; 13:5. [PMID: 38212805 PMCID: PMC10785461 DOI: 10.1186/s40249-024-01174-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 01/03/2024] [Indexed: 01/13/2024] Open
Abstract
BACKGROUND There is increasing epidemiological evidence supporting the association between onchocerciasis and seizures, reinforcing the concept of onchocerciasis-associated epilepsy (OAE). The aim of this paper is to provide an update on the new knowledge about OAE and to propose recommendations to the World Health Organization how to address this public health problem. MAIN TEXT During the 2nd International Workshop on OAE held on 19-21 September, 2023, in Antwerp, Belgium, participants recognised OAE as a substantial yet neglected public health problem, particularly in areas of sub-Saharan Africa where onchocerciasis remains hyperendemic. Evidence from prospective population-based studies suggest that strengthening onchocerciasis elimination efforts leads to a significant reduction of OAE incidence. There is a need to validate an OAE case definition to estimate the burden of disease and identify onchocerciasis-endemic areas requiring intensification of onchocerciasis elimination programmes and integration of epilepsy care. It is expected that raising awareness about OAE will boost the population uptake of ivermectin. The implementation of a community-based epilepsy treatment programme offering free anti-seizure medications (ASMs) has shown high effectiveness in reducing the frequency of seizures and improving the overall quality of life of people with epilepsy. CONCLUSIONS To reduce OAE burden, enhanced collaboration between onchocerciasis and mental health programmes at community, national, and international levels is required. Urgent efforts are needed to ensure the uninterrupted provision of free ASMs in onchocerciasis-endemic areas. Furthermore, OAE should be included in the quantification of the onchocerciasis disease burden.
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Affiliation(s)
| | | | - Olivia Kamoen
- Department of Neurology, Heilig Hart Ziekenhuis, Lier, Belgium
| | | | - Amber Hadermann
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Chiara Trevisan
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Mark J Taylor
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - Julia Gauglitz
- Department of Computer Science, University of Antwerp, Antwerp, Belgium
| | - Achim Hoerauf
- Institute of Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Yasuaki Sato
- School of Global Humanities and Social Sciences, Nagasaki University, Nagasaki, Japan
| | - Katja Polman
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - María-Gloria Basáñez
- MRC Centre for Global Infectious Disease Analysis and London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - Dan Bhwana
- National Institute for Medical Research, Tanga, Tanzania
| | - Thomson Lakwo
- Vector Control Division, Ministry of Health, Kampala, Uganda
| | - Gasim Abd-Elfarag
- School of Public Health, University of Juba, Juba, South Sudan
- Access for Humanity, Juba, South Sudan
| | - Sébastien D Pion
- French National Research Institute for Sustainable Development, Montpellier, France
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11
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Portela CS, Mendes de Araújo CP, Moura Sousa P, Gomes Simão CL, Silva de Oliveira JC, Crainey JL. Filarial disease in the Brazilian Amazon and emerging opportunities for treatment and control. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2023; 5:100168. [PMID: 38283060 PMCID: PMC10821485 DOI: 10.1016/j.crpvbd.2023.100168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/06/2023] [Accepted: 12/15/2023] [Indexed: 01/30/2024]
Abstract
Following the successful eradication of Wuchereria bancrofti, there are now just three species of conventional microfilaremic human filarial parasites endemic to the Brazilian Amazon region: Mansonella ozzardi, Mansonella perstans and Onchocerca volvulus. The zoonotic filarial parasite Dirofilaria immitis is also found in the Amazon region as are several sylvatic filarial parasites, some of which have been recorded causing zoonoses and some of which have never been recorded outside the region. Onchocerca volvulus is only found in the Amazonia onchocerciasis focus in the Brazilian state of Roraima where it affects the people of the Yanomami tribe living around the densely forested Venezuela border region. Mansonella ozzardi is by far the most common filarial parasite in Brazil and has a broad but patchy distribution throughout the western Amazon region. Recorded in the Brazilian states of Acre, Roraima, Matto Grosso, and within almost every municipality of Amazonas state, it is believed that pollution of the urban stream and river systems prevents the development of the simuliid vectors of M. ozzardi and explains the parasite's reduced distribution within urban areas and an absence of recent reports from the state capital Manaus. Decades of WHO-led periodic ivermectin treatment of Yanomami tribe's people have resulted in the partial suppression of O. volvulus transmission in this focus and has also probably affected the transmission of M. ozzardi in the region. Mansonella perstans, O. volvulus and very probably M. ozzardi infections can all be treated and most likely cured with a 4-6-week treatment course of doxycycline. The Brazilian Ministry of Health does not, however, presently recommend any treatment for mansonellosis infections and thus parasitic infections outside the Amazonia focus are typically left untreated. While the long treatment courses required for doxycycline-based mansonellosis therapies preclude their use in control programmes, new fast-acting filarial drug treatments are likely to soon become available for the treatment of both onchocerciasis and mansonellosis in the Amazon region. Filarial disease management in the Brazilian Amazon is thus likely to become dramatically more viable at a time when the public health importance of these diseases is increasingly being recognized.
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Affiliation(s)
- Cleudecir Siqueira Portela
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Biologia da Interação Patógeno Hospedeiro, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Cláudia Patrícia Mendes de Araújo
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Biologia da Interação Patógeno Hospedeiro, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Patrícia Moura Sousa
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Biologia da Interação Patógeno Hospedeiro, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Carla Letícia Gomes Simão
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Mestrado em Condições de Vida e Situações de Saúde na Amazônia, Instituto Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - João Carlos Silva de Oliveira
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
- Programa de Doutorado em Saúde Pública na Amazônia, Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Manaus, Amazonas, Brazil
| | - James Lee Crainey
- Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz Amazônia, Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Manaus, Amazonas, Brazil
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12
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Edridge AWD, Abd-Elfarag G, Verhoef H, van der Hoek L, Boele van Hensbroek M. Response to: 'Methodological challenges for conducting case control studies to investigate the association between onchocerciasis and epilepsy including nodding syndrome'. Brain Commun 2023; 6:fcad339. [PMID: 38162900 PMCID: PMC10755344 DOI: 10.1093/braincomms/fcad339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 11/14/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024] Open
Affiliation(s)
- Arthur W D Edridge
- Amsterdam Centre for Global Child Health, Emma’s Paediatric Hospital, Amsterdam UMC, location University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, location University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Gasim Abd-Elfarag
- Amsterdam Centre for Global Child Health, Emma’s Paediatric Hospital, Amsterdam UMC, location University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Neurology & Psychiatry, College of Medicine, University of Juba, P.O. Box 82, Juba, South Sudan
| | - Hans Verhoef
- Division of Human Nutrition and Health, Wageningen University, 6701 AR Wageningen, The Netherlands
| | - Lia van der Hoek
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, location University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Michael Boele van Hensbroek
- Amsterdam Centre for Global Child Health, Emma’s Paediatric Hospital, Amsterdam UMC, location University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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13
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Molyneux DH. Mental health and neglected tropical diseases - the neglected dimension of burden: identifying the challenges and understanding the burden. Int Health 2023; 15:iii3-iii6. [PMID: 38118153 PMCID: PMC10732677 DOI: 10.1093/inthealth/ihad065] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/25/2023] [Indexed: 12/22/2023] Open
Abstract
Mental health co-morbidity and the Neglected Tropical Diseases (NTDs) has been highlighted as a major component of the ill health. The impact of mental illness is considered to be significantly underestimated in the calculations of the overall Disability-Adjusted Life Years (DALYs). This commentary discusses the DALY burden of anxiety, depression and associated stigma of NTDs. The economic losses incurred as a result of mental health conditions is assessed, and the impact on caregivers and families. It recommends that mental health care is incorporated into NTDs programme planning and implementation. Priority research is the estimation of the NTD burden of depressive and anxiety disorders and neuropsychiatric conditions of NTDs and an evaluation of the economic costs of mental illness derived from NTDs causation.
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Affiliation(s)
- David H Molyneux
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
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14
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Hadermann A, Jada SR, Sebit WJ, Deng T, Bol YY, Siewe Fodjo JN, De Coninck L, Matthijnssens J, Mertens I, Polman K, Colebunders R. Onchocerciasis-associated epilepsy: an explorative case-control study with viral metagenomic analyses on Onchocerca volvulus. F1000Res 2023; 12:1262. [PMID: 38439783 PMCID: PMC10911407 DOI: 10.12688/f1000research.138774.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/06/2023] [Indexed: 03/06/2024] Open
Abstract
Background A high prevalence of onchocerciasis-associated epilepsy (OAE) has been observed in onchocerciasis-endemic areas with high ongoing Onchocerca volvulus transmission. However, the pathogenesis of OAE remains to be elucidated. We hypothesise that the O. volvulus virome could be involved in inducing epilepsy. With this study, we aim to describe the O. volvulus virome and identify potential neurotropic viruses linked to OAE. Methods In Maridi County, an onchocerciasis endemic area in South Sudan with a high prevalence of OAE, we will conduct an exploratory case-control study enrolling 40 persons aged 12 years and above with palpable onchocerciasis nodules. Cases will be participants with OAE (n=20), who will be age- and village-matched with controls without epilepsy (n=20). For each study participant, two skin snips at the iliac crest will be obtained to collect O. volvulus microfilariae, and one nodulectomy will be performed to obtain adult worms. A viral metagenomic study will be conducted on microfilariae and adult worms, and the O. volvulus virome of persons with and without OAE will be compared. The number, size, and localisation of onchocerciasis nodules in persons with and without OAE will be described. Moreover, the pre- and post-nodulectomy frequency of seizures in persons with OAE will be compared. Ethics and dissemination The protocol has been approved by the Ethics Committee of the University of Antwerp and the Ministry of Health of South Sudan. Findings will be disseminated nationally and internationally via meetings and peer-reviewed publications. Registration ClinicalTrials.gov registration NCT05868551 ( https://clinicaltrials.gov/study/NCT05868551). Protocol version 1.1, dated 09/05/2023.
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Affiliation(s)
- Amber Hadermann
- Global Health Institute, University of Antwerp, Antwerp, 2610, Belgium
| | | | - Wilson J. Sebit
- Public Health Laboratory, Ministry of Health South Sudan, Juba, South Sudan
| | | | - Yak Y. Bol
- Neglected Tropical Diseases Unit, Ministry of Health South Sudan, Juba, South Sudan
| | | | - Lander De Coninck
- Laboratory of Viral Metagenomics, KU Leuven, Leuven, Flanders, 3000, Belgium
| | - Jelle Matthijnssens
- Laboratory of Viral Metagenomics, KU Leuven, Leuven, Flanders, 3000, Belgium
| | - Inge Mertens
- Health Unit, VITO (Vlaamse Instelling voor Technologisch Onderzoek), Mol, 2400, Belgium
- Centre for Proteomics, University of Atwerp, Antwerp, Belgium
| | - Katja Polman
- Department of Health Sciences, VU Amsterdam, Amsterdam, 1081, The Netherlands
- Department Public Health, Institute of Tropical Medicine, Antwerp, 2600, Belgium
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15
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Mansour A, Rodriguez L, Mansour H, Yehia M, Battaglia Parodi M. Presumed Onchocerciasis Chorioretinitis Spilling over into North America, Europe and Middle East. Diagnostics (Basel) 2023; 13:3626. [PMID: 38132210 PMCID: PMC10743067 DOI: 10.3390/diagnostics13243626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 11/26/2023] [Accepted: 11/30/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Newer generation ophthalmologists practicing in the developed world are not very familiar with some tropical ocular diseases due to the absence of reports in the ophthalmic literature over the past thirty years. Because of world globalization or due to influx of immigrants from sub-Saharan Africa, exotic retinal diseases are being encountered more often in ophthalmology clinics. METHODS A multicenter case series of chorioretinitis or optic neuritis with obscure etiology that used serial multimodal imaging. RESULTS Four cases qualified with the diagnosis of presumed ocular onchocerciasis based on their residence near fast rivers in endemic areas, multimodal imaging, long term follow-up showing progressive disease and negative workup for other diseases. Characteristic findings include peripapillary choroiditis with optic neuritis or atrophy, subretinal tracts of the microfilaria, progressive RPE atrophy around heavily pigmented multifocal chorioretinal lesions of varying shapes, subretinal white or crystalline dots, and response to ivermectin. Typical skin findings are often absent in such patients with chorioretinitis rendering the diagnosis more challenging. CONCLUSIONS Familiarity with the myriad ocular findings of onchocerciasis, and a high-degree of suspicion in subjects residing in endemic areas can help in the correct diagnosis and implementation of appropriate therapy. Onchocercal chorioretinitis is a slow, insidious, progressive, and prolonged polymorphous disease.
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Affiliation(s)
- Ahmad Mansour
- Retina Service, Department of Ophthalmology, American University of Beirut, Beirut 1107, Lebanon
| | - Linnet Rodriguez
- Retina Service, Wills Eye Hospital, Thomas Jefferson Medical Center, Philadelphia, PA 19107, USA; (L.R.); (H.M.)
| | - Hana Mansour
- Retina Service, Wills Eye Hospital, Thomas Jefferson Medical Center, Philadelphia, PA 19107, USA; (L.R.); (H.M.)
| | - Madeleine Yehia
- Retina Service, University of Illinois Chicago, Chicago, IL 60612, USA;
| | - Maurizio Battaglia Parodi
- Retina Service, Department of Ophthalmology, Ospedale San Raffaele, University Vita-Salute, 20132 Milan, Italy;
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Tunali V, Korkmaz M. Emerging and Re-Emerging Parasitic Infections of the Central Nervous System (CNS) in Europe. Infect Dis Rep 2023; 15:679-699. [PMID: 37987400 PMCID: PMC10660548 DOI: 10.3390/idr15060062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 10/12/2023] [Accepted: 10/20/2023] [Indexed: 11/22/2023] Open
Abstract
In a rapidly evolving global landscape characterized by increased international travel, migration, and ecological shifts, this study sheds light on the emergence of protozoal and helminthic infections targeting the central nervous system (CNS) within Europe. Despite being traditionally associated with tropical regions, these infections are progressively becoming more prevalent in non-endemic areas. By scrutinizing the inherent risks, potential outcomes, and attendant challenges, this study underscores the intricate interplay between diagnostic limitations, susceptibility of specific population subsets, and the profound influence of climate fluctuations. The contemporary interconnectedness of societies serves as a conduit for introducing and establishing these infections, warranting comprehensive assessment. This study emphasizes the pivotal role of heightened clinician vigilance, judicious public health interventions, and synergistic research collaborations to mitigate the potential consequences of these infections. Though rare, their profound impact on morbidity and mortality underscores the collective urgency required to safeguard the neurological well-being of the European populace. Through this multifaceted approach, Europe can effectively navigate the complex terrain posed with these emergent infections.
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Affiliation(s)
- Varol Tunali
- Department of Parasitology, Faculty of Medicine, Manisa Celal Bayar University, 45030 Manisa, Turkey
- Department of Emergency Medicine, Izmir Metropolitan Municipality Eşrefpaşa Hospital, 35170 Izmir, Turkey
| | - Metin Korkmaz
- Department of Parasitology, Faculty of Medicine, Ege University, 35100 Izmir, Turkey;
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17
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Bhwana D, Siewe Fodjo JN, Amaral LJ, Vandevenne L, Francis F, Challe DP, Mmbando BP, Colebunders R. Disability assessment among persons with epilepsy in Mahenge, an onchocerciasis-endemic area in Tanzania: A cross-sectional study. Epilepsy Behav 2023; 146:109367. [PMID: 37523798 DOI: 10.1016/j.yebeh.2023.109367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/17/2023] [Accepted: 07/20/2023] [Indexed: 08/02/2023]
Abstract
BACKGROUND A high prevalence of epilepsy has been observed in the onchocerciasis-endemic focus of Mahenge, Tanzania. This study sought to assess the degree of disability experienced by persons with epilepsy (PWE) in Mahenge and identify associations with sociodemographic and clinical features. METHOD This cross-sectional study was conducted in Mahenge, Tanzania, between February and July 2020. PWE were recruited from the Mahenge epilepsy clinic and four neighbouring rural villages (Mdindo, Mzogezi, Mzelezi and Sali). Data were collected using the 36-item version of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) questionnaire for adults. For children aged 5-17 years, we used the Module on Child Functioning developed by UNICEF and the Washington Group. Questionnaires were administered by trained research assistants. Descriptive statistics were performed, and multivariable analyses (gamma and logistic regressions) were conducted. RESULTS A total of 321 adults (45.5% males) and 48 children (55.3% males) with epilepsy participated. The overall median WHODAS 2.0 score was 4.8% (IQR: 0.9-18.9). The most affected disability domain was 'participating in the society' (median score: 12.5%, IQR: 0-29.2). Fifteen (31.3%) of the children with epilepsy had a disability in at least one domain of the child functioning module, with the 'accepting change' domain harbouring the highest proportion of disabled children (12.5%). Higher seizure frequency and longer epilepsy duration were associated with more disability. CONCLUSION PWE in Mahenge experience variable degrees of disability. The affected domains indicate the need for societal rehabilitation of PWE in various community and/or social activities. Peer-support groups were instituted at the study sites to address these needs.
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Affiliation(s)
- Dan Bhwana
- National Institute of Medical Research, Tanga, P.O Box 5004, Tanzania.
| | | | - Luís-Jorge Amaral
- Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium.
| | - Lauren Vandevenne
- Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium.
| | - Filbert Francis
- National Institute of Medical Research, Tanga, P.O Box 5004, Tanzania.
| | - Daniel P Challe
- National Institute of Medical Research, Tanga, P.O Box 5004, Tanzania.
| | - Bruno P Mmbando
- National Institute of Medical Research, Tanga, P.O Box 5004, Tanzania.
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Colebunders R, Hadermann A, Siewe Fodjo JN. The onchocerciasis hypothesis of nodding syndrome. PLoS Negl Trop Dis 2023; 17:e0011523. [PMID: 37590176 PMCID: PMC10434893 DOI: 10.1371/journal.pntd.0011523] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023] Open
Abstract
Nodding syndrome (NS) is a phenotypic presentation of onchocerciasis-associated epilepsy (OAE). OAE is an important public health problem in areas with high ongoing Onchocerca volvulus transmission. OAE, including NS, is preventable by strengthening onchocerciasis elimination programs. The presence of tau in OAE postmortem brains could be the consequence of neuroinflammation directly or indirectly induced by O. volvulus. Omics research is needed to investigate whether O. volvulus worms contain a neurotropic virus.
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Affiliation(s)
| | - Amber Hadermann
- Global Health Institute University of Antwerp, Antwerp, Belgium
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Amaral LJ, Bhwana D, Mhina AD, Mmbando BP, Colebunders R. Nodding syndrome, a case-control study in Mahenge, Tanzania: Onchocerca volvulus and not Mansonella perstans as a risk factor. PLoS Negl Trop Dis 2023; 17:e0011434. [PMID: 37339148 DOI: 10.1371/journal.pntd.0011434] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 06/05/2023] [Indexed: 06/22/2023] Open
Abstract
BACKGROUND Nodding syndrome (NS) has been consistently associated with onchocerciasis. Nevertheless, a positive association between NS and a Mansonella perstans infection was found in South Sudan. We aimed to determine whether the latter parasite could be a risk factor for NS in Mahenge. METHODS Cases of epilepsy were identified in villages affected by NS in Mahenge, Tanzania, and matched with controls without epilepsy of the same sex, age and village. We examined blood films of cases and controls to identify M. perstans infections. The participants were also asked for sociodemographic and epilepsy information, examined for palpable onchocercal nodules and onchocerciasis-related skin lesions and tested for anti-Onchocerca volvulus antibodies (Ov16 IgG4) by ELISA. Clinical characteristics of cases and controls, O. volvulus exposure status and relevant sociodemographic variables were assessed by a conditional logistic regression model for NS and epilepsy status matched for age, sex and village. RESULTS A total of 113 epilepsy cases and 132 controls were enrolled, of which, respectively, 56 (49.6%) and 64 (48.5%) were men. The median age in cases and controls was 28.0 (IQR: 22.0-35.0) and 27.0 (IQR: 21.0-33.3) years. Of the persons with epilepsy, 43 (38.1%) met the probable NS criteria and 106 (93.8%) had onchocerciasis-associated epilepsy (OAE). M. perstans infection was absent in all participants, while Ov16 seroprevalence was positively associated with probable NS (odds ratio (OR): 5.05, 95%CI: 1.79-14.27) and overall epilepsy (OR: 2.03, 95%CI: 1-07-3.86). Moreover, onchocerciasis-related skin manifestations were only found in the cases (n = 7, p = 0.0040), including persons with probable NS (n = 4, p = 0.0033). Residing longer in the village and having a family history of seizures were positively correlated with Ov16 status and made persons at higher odds for epilepsy, including probable NS. CONCLUSION In contrast to O. volvulus, M. perstans is most likely not endemic to Mahenge and, therefore, cannot be a co-factor for NS in the area. Hence, this filaria is unlikely to be the primary and sole causal factor in the development of NS. The main risk factor for NS remains onchocerciasis.
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Affiliation(s)
| | - Dan Bhwana
- National Institute of Medical Research, Tanga, Tanzania
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20
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Amaral LJ, Bhwana D, Fomo MF, Mmbando BP, Chigoho CN, Colebunders R. Quality of life of persons with epilepsy in Mahenge, an onchocerciasis-endemic area in Tanzania: A cross-sectional study. Epilepsy Behav 2023; 145:109302. [PMID: 37336132 DOI: 10.1016/j.yebeh.2023.109302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/02/2023] [Accepted: 06/02/2023] [Indexed: 06/21/2023]
Abstract
OBJECTIVE This study investigated the quality of life (QoL) of adults with epilepsy living in Mahenge, an onchocerciasis-endemic area in Tanzania with a high prevalence of onchocerciasis-associated epilepsy (OAE). METHODS Between February and December 2020, persons with epilepsy (PWE) were recruited from four rural villages in Mahenge: Mdindo, Msogezi, Mzelezi, and Sali. For PWE who could not answer the questionnaire due to their mental or physical disability, a family member was asked to answer the questions instead. The Quality of Life in Epilepsy Inventory-31 (QOLIE-31) questionnaire used contained seven domains. The raw domain scores were transformed to 0-100% subscales, with higher scores indicating better QoL. The global QoL was calculated from the subscales using the overall QOLIE-31 score formula. RESULTS In total, 96 PWE were enrolled in the study with a median age of 28 (range: 18-60) years, of whom 45 (47%) were male. The questionnaires were answered by PWE (54.8%) or one of their family members (45.2%). Most PWE were single (81%), and half never attended school. About two-thirds (65%) of PWE were suspected of having OAE, and a third (31%) had a history of head nodding seizures. Most PWE were treated with phenobarbital (85.4%) and had high treatment adherence (96.9%). Still, the number of seizures per week ranged from 0 to 7, with a median of one. The mean global QOLIE-31 score was 66.9 (range: 38.3-92.1) out of 100.0. Predictors of lower QoL were living in Sali Village and experiencing seizures the week before the interview. In contrast, completing primary school and switching to second-line anti-seizure medication were predictors of higher QoL. CONCLUSION In order to improve the QoL of PWE in Mahenge, it is vital to optimize anti-seizure medication regimens to decrease the frequency of seizures and to increase the schooling of PWE.
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Affiliation(s)
| | - Dan Bhwana
- National Institute of Medical Research, Tanga, P.O. Box 5004, Tanzania
| | - Messaline F Fomo
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Bruno P Mmbando
- National Institute of Medical Research, Tanga, P.O. Box 5004, Tanzania
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Ngarka L, Siewe Fodjo JN, Ambomatei C, Njamnshi WY, Taryunyu Njamnshi JN, Nfor LN, Mengnjo MK, Njamnshi AK. Epidemiology of epilepsy and relationship with onchocerciasis prevalence in villages of the Ntui Health District of Cameroon. Epilepsy Behav 2023; 142:109184. [PMID: 36972641 PMCID: PMC7614422 DOI: 10.1016/j.yebeh.2023.109184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 03/29/2023]
Abstract
BACKGROUND A strong association between epilepsy and onchocerciasis endemicity has been reported. We sought to document the epidemiology of epilepsy in onchocerciasis-endemic villages of the Ntui Health District in Cameroon and investigate how this relates to the prevalence of onchocerciasis. METHODS In March 2022, door-to-door epilepsy surveys were conducted in four villages (Essougli, Nachtigal, Ndjame, and Ndowe). Ivermectin intake during the 2021 session of community-directed treatment with ivermectin (CDTI) was investigated in all participating village residents. Persons with epilepsy (PWE) were identified through a two-step approach: administration of a 5-item epilepsy screening questionnaire followed by clinical confirmation by a neurologist. Epilepsy findings were analyzed together with onchocerciasis epidemiological data previously obtained in the study villages. RESULTS We surveyed 1663 persons in the four study villages. The 2021 CDTI coverage for all study sites was 50.9%. Overall, 67 PWE were identified (prevalence of 4.0% (IQR: 3.2-5.1) with one new-onset case during the past 12 months (annual incidence of 60.1 per 100,000 persons). The median age of PWE was 32 years (IQR: 25-40), with 41 (61.2%) being females. The majority (78.3%) of PWE met the previously published criteria for onchocerciasis-associated epilepsy (OAE). Persons with a history of nodding seizures were found in all villages and represented 19.4% of the 67 PWE. Epilepsy prevalence was positively correlated with onchocerciasis prevalence (Spearman Rho = 0.949, p = 0.051). Meanwhile, an inverse relationship was observed between distance from the Sanaga river (blackfly breeding site) and the prevalence of both epilepsy and onchocerciasis. CONCLUSION The high epilepsy prevalence in Ntui appears to be driven by onchocerciasis. It is likely that decades of CDTI have likely contributed to a gradual decrease in epilepsy incidence, as only one new case occurred in the past year. Therefore, more effective elimination measures are urgently needed in such endemic areas to curb the OAE burden.
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Affiliation(s)
- Leonard Ngarka
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon; Neurology Department, Central Hospital Yaoundé, Yaoundé, Cameroon; Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon.
| | - Joseph Nelson Siewe Fodjo
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon; Division of Operational Research in Health, Ministry of Public Health, Yaoundé, Cameroon.
| | | | - Wepnyu Yembe Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon; Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon; Division of Operational Research in Health, Ministry of Public Health, Yaoundé, Cameroon.
| | | | - Leonard N Nfor
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon; Neurology Department, Central Hospital Yaoundé, Yaoundé, Cameroon.
| | - Michel K Mengnjo
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon; Neurology Department, Central Hospital Yaoundé, Yaoundé, Cameroon.
| | - Alfred K Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon; Neurology Department, Central Hospital Yaoundé, Yaoundé, Cameroon; Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon.
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Van Cutsem G, Siewe Fodjo JN, Dekker MCJ, Amaral LJ, Njamnshi AK, Colebunders R. Case definitions for onchocerciasis-associated epilepsy and nodding syndrome: A focused review. Seizure 2023; 107:132-135. [PMID: 37023626 DOI: 10.1016/j.seizure.2023.03.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/03/2023] Open
Abstract
Onchocerciasis-associated epilepsy (OAE) is an important but neglected public health problem in onchocerciasis-endemic areas with insufficient or inadequate onchocerciasis control. Hence, there is a need for an internationally accepted, easy-to-use epidemiological case definition of OAE to identify areas of high Onchocerca volvulus transmission and disease burden requiring treatment and prevention interventions. By including OAE as a manifestation of onchocerciasis, we will considerably improve the accuracy of the overall onchocerciasis disease burden, which is currently underestimated. Hopefully, this will lead to increased interest and funding for onchocerciasis research and control interventions, notably the implementation of more effective elimination measures and treatment and support for affected individuals and their families.
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