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Shintouo CM, Shey RA, Yengo BN, Yaah NE, Teh RN, Ngwese RA, Ayong L, Vanhamme L, Souopgui J, Ghogomu SM, Njemini R. Effects of the suspension of mass drug administration during the COVID-19 pandemic on onchocerciasis prevalence in the Bandjoun and Massangam health districts, West Region of Cameroon. Acta Trop 2023; 246:106999. [PMID: 37549841 DOI: 10.1016/j.actatropica.2023.106999] [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: 03/06/2023] [Revised: 07/26/2023] [Accepted: 08/04/2023] [Indexed: 08/09/2023]
Abstract
Onchocerciasis is an infectious disease of public health and socio-economic importance in most parts of Sub-Saharan Africa. The objective of this study was to evaluate the effects of the suspension of implementation activities towards combating onchocerciasis in the Bandjoun and Massangam health districts in the West Region of Cameroon as a consequence of the COVID-19 pandemic. Data on socio-demographic and clinical characteristics were obtained using a structured questionnaire. All participants in both health districts were examined for the presence of clinical manifestations of onchocerciasis. In addition, two skin snips were obtained from the knee of each participant and examined for the presence of microfilaria. All data were categorized, coded, entered in a database, and analysed using SPSS version 23.0. A total of 229 participants in the Bandjoun health district and 378 in the Massangam health district were recruited for the study. In both health districts, there was no significant difference between male and female participants in terms of the clinical manifestations of onchocerciasis. The prevalence of nodules was 8.7% in the Bandjoun health district and 20.6% in the Massangam health district while the prevalence of microfilaria carriers in Bandjoun and Massangam health districts was 3.5% and 3.7%, respectively. Except for the Tsesse and Lemgo communities in the Bandjoun health district, there was a reduction in the prevalence of microfilaria in the communities that were studied when compared to previous data obtained before the disruption of control programmes activities. Overall, in both health districts, elderly individuals bear the largest burden of onchocerciasis. Based on the results obtained, we conclude that the temporary suspension of Neglected Tropical Disease control programme activities by the World Head Organization as a result of COVID-19 may have resulted to recrudescence of O. volvulus transmission in hypoendemic communities in the Bandjoun health district.
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Affiliation(s)
- Cabirou Mounchili Shintouo
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium; Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium; Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon
| | - Robert Adamu Shey
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon; Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 126040 Gosselies, Belgium
| | - Bernis Neneyoh Yengo
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon
| | - Ntang Emmaculate Yaah
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon
| | - Rene Ning Teh
- Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon
| | - Roland Akwelle Ngwese
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon
| | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde´, Cameroon
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 126040 Gosselies, Belgium
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 126040 Gosselies, Belgium.
| | - Stephen Mbigha Ghogomu
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon.
| | - Rose Njemini
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium; Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.
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Yengo BN, Shintouo CM, Hotterbeekx A, Yaah NE, Shey RA, Quanico J, Baggerman G, Ayong L, Vanhamme L, Njemini R, Souopgui J, Colebunders R, Ghogomu SM. Immunoinformatics Design and Assessment of a Multiepitope Antigen (OvMCBL02) for Onchocerciasis Diagnosis and Monitoring. Diagnostics (Basel) 2022; 12:diagnostics12061440. [PMID: 35741250 PMCID: PMC9221995 DOI: 10.3390/diagnostics12061440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 05/28/2022] [Accepted: 06/09/2022] [Indexed: 11/23/2022] Open
Abstract
Onchocerciasis is a Neglected Tropical Disease that has a significant socioeconomic impact, especially in Sub-Saharan Africa. Numerous reports indicate that the Expanded Special Project for the Elimination of Neglected Tropical Diseases needs novel diagnostic tools before achieving its goal of successful elimination of onchocerciasis in Africa. The current diagnostic tests are either invasive, insensitive, or not applicable in the field and about 25% of persons infected cannot mount immune responses against the single antigen used in the only approved Ov-16 serological test. In the quest to identify novel biomarkers that can be used to certify that a patient is free from the disease, evaluate the progress of elimination programmes, and conduct post elimination surveillances, mass spectrometric analysis of Onchocerca volvulus crude extract revealed that 1392 proteins are expressed in the adult and microfilariae stages of the parasite. Computational analysis predicted six of the proteins as O. volvulus potential diagnostic targets. Linear B-epitopes were predicted from the six proteins and used to construct a multiepitope antigen (OvMCBL02). Serological analysis revealed that the OvMCBL02 test significantly differentiated between serum samples of onchocerciasis patients from the Kombone Health Area in the South West Region of Cameroon (n = 63) and control serum samples from Rwanda (n = 29) and Europe (n = 26) as well as between serum samples from the onchocerciasis hyperendemic region of Kombone Health Area (n = 63) and the hypoendemic region of Bandjoun Health District (n = 54). Interestingly, the test did not cross-react with serum samples from patients suffering from related nematode infections, thereby suggesting that further characterization of the OvMCBL02 multiepitope antigen will render it an additional member of the diagnostic toolbox for the elimination of onchocerciasis.
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Affiliation(s)
- Bernis Neneyoh Yengo
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (B.N.Y.); (C.M.S.); (N.E.Y.); (R.A.S.)
| | - Cabirou Mounchili Shintouo
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (B.N.Y.); (C.M.S.); (N.E.Y.); (R.A.S.)
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium;
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - An Hotterbeekx
- Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium; (A.H.); (R.C.)
- Molecular Pathology Group, Laboratory of Cell biology and Histology, University of Antwerp, 2610 Antwerp, Belgium
| | - Ntang Emmaculate Yaah
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (B.N.Y.); (C.M.S.); (N.E.Y.); (R.A.S.)
| | - Robert Adamu Shey
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (B.N.Y.); (C.M.S.); (N.E.Y.); (R.A.S.)
| | - Jusal Quanico
- Center for Proteomics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium; (J.Q.); (G.B.)
| | - Geert Baggerman
- Center for Proteomics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium; (J.Q.); (G.B.)
| | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur Cameroon, Yaoundé P.O. Box 1274, Cameroon;
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Gosselies Campus, Université Libre de Bruxelles, 1070 Brussels, Belgium; (L.V.); (J.S.)
| | - Rose Njemini
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium;
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Gosselies Campus, Université Libre de Bruxelles, 1070 Brussels, Belgium; (L.V.); (J.S.)
| | - Robert Colebunders
- Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium; (A.H.); (R.C.)
| | - Stephen Mbigha Ghogomu
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (B.N.Y.); (C.M.S.); (N.E.Y.); (R.A.S.)
- Correspondence: ; Tel.: +237-6-7845-5646
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Capture of high numbers of Simulium vectors can be achieved with Host Decoy Traps to support data acquisition in the onchocerciasis elimination endgame. Acta Trop 2021; 221:106020. [PMID: 34157291 PMCID: PMC8326245 DOI: 10.1016/j.actatropica.2021.106020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 05/25/2021] [Accepted: 06/12/2021] [Indexed: 11/24/2022]
Abstract
Onchocerciasis elimination is within reach in many countries but requires enhanced surveillance of the Simulium vectors of Onchocerca volvulus. Collection of sufficient numbers of adult Simulium to detect infective O. volvulus larvae is hindered by limited sampling tools for these flies. Here, we tested for the first time the Host Decoy Trap (HDT), an exposure free method previously developed for Anopheles vectors of malaria parasites, as a potential sampling tool for adult Simulium. In three replicates of a randomized Latin square experimental design, the HDT was compared to Human Landing Catches (HLC) and the Esperanza Window Trap (EWT). A total of 8,531 adult S. damnosum sensu lato blackflies (S. squamosum group) were found in catches from the three different trapping methods. The HDT (mean catch 533 ± 111) caught significantly more S. squamosum than the EWT (mean catch 9.1 ± 2.2), a nearly 60-fold difference. There was no significant difference between the HLC (mean catch 385.6 ± 80.9) and the HDT. Larvae indistinguishable from those of O. volvulus were dissected from 2.86% of HDT samples (n = 70) and 0.35% of HLC samples (n = 285); a single infective third-stage larvae (L3) was found during dissection of a sample from the HDT. Owing to its very high capture rate, which was comparable to the HLC and significantly greater than EWT, alongside the presence of infected flies in its catch, the HDT represents a potentially valuable new tool for blackfly collection in elimination settings, where thousands of flies are needed for parasite screening.
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Nji TM, Piotrowski H, Dum-Buo N, Fung EG, Dean L, Theobald S, Thomson R, Wanji S, Ozano K. Eliminating onchocerciasis within the Meme River Basin of Cameroon: A social-ecological approach to understanding everyday realities and health systems. PLoS Negl Trop Dis 2021; 15:e0009433. [PMID: 34077416 PMCID: PMC8202923 DOI: 10.1371/journal.pntd.0009433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 06/14/2021] [Accepted: 05/02/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Onchocerciasis affects some of the world's most marginalized people, perpetuating poverty and inequalities. Mass Drug Administration (MDA) with Ivermectin has taken place within the Meme River basin region in Cameroon for over 15 years. Despite this, onchocerciasis is still prevalent in the region due to existing and emerging contextual challenges. Using a social-ecological approach we explore the everyday realities of communities, highlighting the challenges and potential solutions that could support Neglected Tropical Disease (NTD) programmes when transitioning from control to elimination of onchocerciasis in this highly endemic area and other similar communities. METHODOLOGY/PRINCIPAL FINDING In-depth interviews (71) with community members and Community Drug Distributors (CDDs) were conducted to understand current knowledge, attitudes, and behaviours in relation to transmission, prevention and treatment of onchocerciasis. Through application of the social-ecological model, four key themes were identified: 1. Contextual factors on health promotion interventions (Onchocerciasis history and understanding of the disease, prevention and mitigation strategies and MDA experience); 2. Social determinants (poverty and livelihoods, economic and social impacts on CDD volunteers and stigma); 3. Environmental determinants (exposure, housing, occupation and poverty); and 4. health seeking pathways and decision making for treatment (access, cost and preferable treatment routes). We discuss these core and cross cutting themes (gender differences and community participation/ownership) in relation to intersectoral collaboration, gender equity and health systems support, making recommendations for NTD programmes within the context of integrated and interdisciplinary approaches. These include the need for; intersectional and gender analysis at the local level, addressing environmental dimensions of onchocerciasis through integrated and regular health promotion, vector control strategies and access to safe water sources; reflection and action that embeds responses to social and economic barriers to MDA; integrated case detection and management that is responsive to onchocerciasis symptoms and related stigma and a fair and just support network for CDDs. CONCLUSION/SIGNIFICANCE NTD programmes need to respond to diverse community circumstances and behaviours. Communities are not a homogeneous risk group and treating them in this way will delay elimination. A deeper understanding of individual needs and their capacity to seek prevention and treatment must be considered if onchocerciasis is to be eliminated and the remaining impacts managed.
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Affiliation(s)
- Theobald Mue Nji
- Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, Research Foundation in Tropical Diseases and Environment, Buea, Cameroon
| | - Helen Piotrowski
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nnamdi Dum-Buo
- Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, Research Foundation in Tropical Diseases and Environment, Buea, Cameroon
| | - Ebua Gallus Fung
- Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, Research Foundation in Tropical Diseases and Environment, Buea, Cameroon
| | - Laura Dean
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Sally Theobald
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Rachael Thomson
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Samuel Wanji
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Research Foundation in Tropical Diseases and Environment, Buea, Cameroon
| | - Kim Ozano
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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5
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Shey RA, Ghogomu SM, Shintouo CM, Nkemngo FN, Nebangwa DN, Esoh K, Yaah NE, Manka’aFri M, Nguve JE, Ngwese RA, Njume FN, Bertha FA, Ayong L, Njemini R, Vanhamme L, Souopgui J. Computational Design and Preliminary Serological Analysis of a Novel Multi-Epitope Vaccine Candidate against Onchocerciasis and Related Filarial Diseases. Pathogens 2021; 10:99. [PMID: 33494344 PMCID: PMC7912539 DOI: 10.3390/pathogens10020099] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 01/14/2021] [Accepted: 01/18/2021] [Indexed: 11/16/2022] Open
Abstract
: Onchocerciasis is a skin and eye disease that exerts a heavy socio-economic burden, particularly in sub-Saharan Africa, a region which harbours greater than 96% of either infected or at-risk populations. The elimination plan for the disease is currently challenged by many factors including amongst others; the potential emergence of resistance to the main chemotherapeutic agent, ivermectin (IVM). Novel tools, including preventative and therapeutic vaccines, could provide additional impetus to the disease elimination tool portfolio. Several observations in both humans and animals have provided evidence for the development of both natural and artificial acquired immunity. In this study, immuno-informatics tools were applied to design a filarial-conserved multi-epitope subunit vaccine candidate, (designated Ov-DKR-2) consisting of B-and T-lymphocyte epitopes of eight immunogenic antigens previously assessed in pre-clinical studies. The high-percentage conservation of the selected proteins and epitopes predicted in related nematode parasitic species hints that the generated chimera may be instrumental for cross-protection. Bioinformatics analyses were employed for the prediction, refinement, and validation of the 3D structure of the Ov-DKR-2 chimera. In-silico immune simulation projected significantly high levels of IgG1, T-helper, T-cytotoxic cells, INF-γ, and IL-2 responses. Preliminary immunological analyses revealed that the multi-epitope vaccine candidate reacted with antibodies in sera from both onchocerciasis-infected individuals, endemic normals as well as loiasis-infected persons but not with the control sera from European individuals. These results support the premise for further characterisation of the engineered protein as a vaccine candidate for onchocerciasis.
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Affiliation(s)
- Robert Adamu Shey
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 6040 Gosselies, Belgium;
| | - Stephen Mbigha Ghogomu
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
| | - Cabirou Mounchili Shintouo
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium;
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Francis Nongley Nkemngo
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea 99999, Cameroon;
- Centre for Research in Infectious Diseases (CRID), Department of Parasitology and Medical Entomology, Yaounde BP 13591, Cameroon
| | - Derrick Neba Nebangwa
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
| | - Kevin Esoh
- Division of Human Genetics, Health Sciences Campus, Department of Pathology, University of Cape Town, Anzio Rd, Observatory, Cape Town 7925, South Africa;
| | - Ntang Emmaculate Yaah
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
| | - Muyanui Manka’aFri
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
| | - Joel Ebai Nguve
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
| | - Roland Akwelle Ngwese
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
| | - Ferdinand Ngale Njume
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea 99999, Cameroon; (R.A.S.); (S.M.G.); (C.M.S.); (D.N.N.); (N.E.Y.); (M.M.); (J.E.N.); (R.A.N.); (F.N.N.)
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 6040 Gosselies, Belgium;
| | - Fru Asa Bertha
- Department of Public Health and Hygiene, Faculty of Health Science, University of Buea, Buea 99999, Cameroon;
| | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur Cameroon, Yaoundé Rue 2005, Cameroon;
| | - Rose Njemini
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium;
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 6040 Gosselies, Belgium;
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 6040 Gosselies, Belgium;
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Abong RA, Amambo GN, Hamid AA, Enow BA, Beng AA, Nietcho FN, Nji TM, Njouendou AJ, Ritter M, Esum ME, Deribe K, Cho JF, Fombad FF, Enyong PI, Poole C, Pfarr K, Hoerauf A, Carlow C, Wanji S. The Mbam drainage system and onchocerciasis transmission post ivermectin mass drug administration (MDA) campaign, Cameroon. PLoS Negl Trop Dis 2021; 15:e0008926. [PMID: 33465080 PMCID: PMC7815102 DOI: 10.1371/journal.pntd.0008926] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 10/27/2020] [Indexed: 11/19/2022] Open
Abstract
Background The impact of large scale Mass Drug Adminstration (MDA) of ivermectin on active onchocerciasis transmission by Simulium damnosum, which transmits the parasite O. volvulus is of great importance for onchocerciasis control programmes. We investigated in the Mbam river system area, the impact of MDA of ivermectin on entomological indices and also verify if there are river system factors that could have favoured the transmission of onchocerciasis in this area and contribute to the persistence of disease. We compared three independent techniques to detect Onchocerca larvae in blackflies and also analyzed the river system within 9 months post-MDA of ivermectin. Method Simulium flies were captured before and after 1, 3, 6 and 9months of ivermectin-MDA. The biting rate was determined and 41% of the flies dissected while the rest were grouped into pools of 100 flies for DNA extraction. The extracted DNA was then subjected to O-150 LAMP and real-time PCR for the detection of infection by Onchocerca species using pool screening. The river system was analysed and the water discharge compared between rainy and dry seasons. Principal findings We used human landing collection method (previously called human bait) to collect 22,274 adult female Simulium flies from Mbam River System. Of this number, 9,134 were dissected while 129 pools constituted for molecular screening. Overall biting and parous rates of 1113 flies/man/day and 24.7%, respectively, were observed. All diagnostic techniques detected similar rates of O. volvulus infection (P = 0.9252) and infectivity (P = 0.4825) at all monitoring time points. Onchocerca ochengi larvae were only detected in 2 of the 129 pools. Analysis of the river drainage revealed two hydroelectric dams constructed on the tributaries of the Mbam river were the key contributing factor to the high-water discharge during both rainy and dry seasons. Conclusion Results from fly dissection (Microscopy), real-time PCR and LAMP revealed the same trends pre- and post-MDA. The infection rate with animal Onchocerca sp was exceptionally low. The dense river system generate important breeding sites that govern the abundance of Simulium during both dry and rainy seasons. The presence of parasite strains that respond sub-optimally to an approved drug, favourable breeding sites for the vector and infected individual in an area, will surely provide conditions for continuous and persistent transmission of a disease despite a long-term control intervention. We investigated the impact of ivermectin on entomological indices within 9 months following a large-scale MDA in the Mbam river drainage. The river system factors that could have favoured abundance vector breeding and contribute to the persistence of disease transmission were also examined within the study period. We observed vector abundance and high entomological indices throughout the study period following ivermectin MDA. We also observed high water discharge along the main river of the drainage basin in both the rainy and dry seasons and this is due to the presence of two dams constructed upstream at Bamendjing and Mape to regularize the course of river Sanaga in view of generating hydroelectric power at Edea. Factors favouring continuous and persistent disease transmission are present in this drainage basin despite over 20 years of annual IVM-MDA. There is need for alternative control strategy in order to accelerate the fight against onchocerciasis in the area.
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Affiliation(s)
- Raphael Awah Abong
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Glory Ngongeh Amambo
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Ali Ahamat Hamid
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Belinda Agbor Enow
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Amuam Andrew Beng
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Franck Noel Nietcho
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Theobald Mue Nji
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
- Department of Sociology and Anthropology, University of Buea, Cameroon
| | - Abdel Jelil Njouendou
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Department of Biomedical science, Faculty of Health Sciences, University of Buea, Buea, Cameroon
| | - Manuel Ritter
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Mathias Eyong Esum
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Kebede Deribe
- Global Health and Infection Department, Brighton and Sussex Medical School, Brighton, United Kingdom
- School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Jerome Fru Cho
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Fanny Fri Fombad
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Peter Ivo Enyong
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Catherine Poole
- New England Biolabs, Ipswich, Massachusetts, United States of America
| | - Kenneth Pfarr
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Clotilde Carlow
- New England Biolabs, Ipswich, Massachusetts, United States of America
| | - Samuel Wanji
- Parasites and Vector Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
- * E-mail:
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7
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Aza'ah RA, Sumo L, Ntonifor NH, Bopda J, Bamou RH, Nana-Djeunga HC. Point prevalence mapping reveals hotspot for onchocerciasis transmission in the Ndikinimeki Health District, Centre Region, Cameroon. Parasit Vectors 2020; 13:519. [PMID: 33066826 PMCID: PMC7565768 DOI: 10.1186/s13071-020-04387-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/06/2020] [Indexed: 11/10/2022] Open
Abstract
Background Ivermectin-based preventive chemotherapy (PC) is distributed annually to all at-risk populations eligible for ivermectin treatment to control and/or eliminate onchocerciasis. Information on the impact of mass ivermectin administration on onchocerciasis transmission is scanty, and it is tricky to appreciate the progress towards elimination and engage corrective measures. To fill that gap in the Centre Region in Cameroon, the current onchocerciasis endemicity level in the Ndikinimeki Health District after about two decades of mass treatments was assessed. Methods A cluster-based cross-sectional survey was carried out in the Ndikinimeki Health District and all volunteers aged ≥ 5 years were (i) interviewed on their compliance to ivermectin over the past five years and (ii) underwent clinical (nodule palpation and visual search for onchocercal lesions) and parasitological examinations (skin snip) for onchocerciasis. Results The overall Onchocerca volvulus prevalence was 7.0% (95% CI: 5.2–9.3%). The prevalence of the disease was significantly higher in the communities Kiboum 1 and Kiboum 2 compared to the other communities (highest prevalence in Makénéné Town Water: 8.5%; 95% CI: 2.3–20.4%) (χ2 = 51.314, df = 11, P = 0.0001). The proportion of systematic non-compliers to ivermectin was 23.3% (95% CI: 19.9–27.1%) among individuals interviewed. In the sentinel sites (Kiboum communities), onchocerciasis prevalence decreased from 95.2% (95% CI: 88.3–98.1%) to 23.7% (95% CI: 14.7–36.0%). Conclusions This study has revealed that the Ndikinimeki Health District is hypo-endemic for onchocerciasis after about two decades of preventive chemotherapy. However, transmission is ongoing, with potential hotspots in the Kiboum 1 and Kiboum 2 communities, which are known as first-line communities (closest to the breeding sites of the vector). Alternative or complementary strategies to annual ivermectin appear compulsory to accelerate the momentum towards onchocerciasis elimination.![]()
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Affiliation(s)
- René Afor Aza'ah
- Department of Biological Sciences, Faculty of Science, University of Bamenda, Bambili, Cameroon
| | - Laurentine Sumo
- Department of Biological Sciences, Faculty of Science, University of Bamenda, Bambili, Cameroon.
| | - Ngum Helen Ntonifor
- Department of Biological Sciences, Faculty of Science, University of Bamenda, Bambili, Cameroon
| | - Jean Bopda
- Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), Yaounde, Cameroon
| | - Rolph H Bamou
- Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), Yaounde, Cameroon
| | - Hugues C Nana-Djeunga
- Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), Yaounde, Cameroon.
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8
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Entomological Assessment of Onchocerca Species Transmission by Black Flies in Selected Communities in the West Region of Cameroon. Pathogens 2020; 9:pathogens9090722. [PMID: 32887231 PMCID: PMC7559537 DOI: 10.3390/pathogens9090722] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 12/20/2022] Open
Abstract
The enormity of the public health burden of onchocerciasis motivated the creation of various large-scale control programs that have depended principally on mass treatment of endemic communities with ivermectin for the elimination of the disease. Parasitological evaluation of Onchocerca species in the West Region of Cameroon indicates significant progress in the interruption of parasite transmission in some communities under ivermectin treatment. However, to verify the complete elimination of onchocerciasis, entomological assessment through O-150 PCR poolscreen of black flies is mandatory. Thus, in the present study, we assessed transmission of Onchocerca species using an O-150 PCR technique to screen pools of black flies—in seven onchocerciasis endemic communities (Makouopsap, Bankambe, Lemgo, Tsesse, Ndionzou, Kouffen, and Bayon) in Cameroon. Two thousand black flies were assessed—in each community—for the presence of Onchocerca species DNA. Our results show that the frequency of infective flies was 0.6% in Makouopsap and 0.0% in the other communities. On the other hand, the frequency of infected flies was 0.8% in Makouopsap, 0.2% in Bankambe, 0.1% in Bayon, and 0.0% in Lemgo, Tsesse, Ndionzou, and Kouffen. These results provide entomologic evidence for continuous transmission of Onchocerca species in Makouopsap, risk of active transmission in Bankambe, and Bayon, and a suppressed transmission in the four other studied communities.
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9
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Gebrezgabiher G, Mekonnen Z, Yewhalaw D, Hailu A. Status of parasitological indicators and morbidity burden of onchocerciasis after years of successive implementation of mass distribution of ivermectin in selected communities of Yeki and Asosa districts, Ethiopia. BMC Public Health 2020; 20:1233. [PMID: 32787813 PMCID: PMC7425055 DOI: 10.1186/s12889-020-09344-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 08/04/2020] [Indexed: 11/23/2022] Open
Abstract
Background Control and elimination of onchocerciasis requires regular follow-up and evaluation of community directed treatment with ivermectin (CDTi) program implementation. This research was aimed to assess the epidemiological status of onchocerciasis in disease endemic communities of Asosa and Yeki districts of Ethiopia after 5 and 15 years of successive CDTi respectively, and to evaluate the decline in infection and morbidity burden. Methods A community-based cross-sectional study was conducted from August 2017 to January 2018 (i.e. within 2–7 months since the last treatment) using interview, physical and parasitological examinations. Pre-CDTi epidemiological data were obtained from studies conducted prior to the launch of CDTi. Results A total of 3002 individuals (1567 from Asosa and 1435 from Yeki) were included. No infection was detected from Yeki. In Asosa, the prevalence of infection was 1.6%. The geometric mean intensity of infection was 0.02 mf/mg of skin snip. The prevalence rates of dermatitis, depigmentation, nodule, and atrophy in Yeki were 33(2.3%), 57(4%), 37(2.6%) and 11(0.7%), respectively. The prevalence rates of papular dermatitis, depigmentation, palpable nodule, atrophy, and blindness in Asosa were 94(6%), 38(2.4%), 30(1.9%), 28(1.8%) and 2(0.1%), respectively. Five years of CDTi had significantly reduced prevalence and intensity of infection by 91.8% (p < 0.001) and 99.7% (p < 0.001), respectively. Moreover, CDTi reduced prevalence of papular dermatitis by 95.9% (p < 0.001), palpable nodule by 90.5% (p < 0.001), and atrophy by 30% (p = 0.6) in Yeki. Similarly, CDTi reduced prevalence of papular dermatitis by 88.6% (p < 0.001), depigmentation by 90.3% (p < 0.001), atrophy by 89.5% (p < 0.001), and blindness by 90% (p < 0.001) in Asosa. Conclusions Fifteen years of successive CDTi had brought the infection from high to zero in Yeki. However, thorough entomological and serological data need to be generated to ascertain whether complete interruption of parasite transmission has been attained, and for considerations of an evidence-based CDTi cessation. Five years of CDTi in Asosa has significantly reduced the infection and morbidity of onchocerciasis to very low level. We, hereby, recommend biannual CDTi to continue in Asosa and its surroundings until the infection transmission is fully interrupted.
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Affiliation(s)
- Gebremedhin Gebrezgabiher
- College of Veterinary Medicine, Samara University, P.O. Box 132, Samara, Ethiopia. .,School of Medical Laboratory Sciences, Institute of Health Sciences, Jimma University, Jimma, Ethiopia.
| | - Zeleke Mekonnen
- School of Medical Laboratory Sciences, Institute of Health Sciences, Jimma University, Jimma, Ethiopia
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Institute of Health Sciences, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Asrat Hailu
- Department of Microbiology, Immunology, and Parasitology, School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
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10
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Tsapi EM, Todjom FG, Gamago GA, Pone JW, Teukeng FFD. Prevalence of onchocerciasis after seven years of continuous community-directed treatment with ivermectin in the Ntui health district, Centre region, Cameroon. Pan Afr Med J 2020; 36:180. [PMID: 32952824 PMCID: PMC7467880 DOI: 10.11604/pamj.2020.36.180.20765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/23/2020] [Indexed: 11/18/2022] Open
Abstract
Introduction onchocerciasis is one of the major infectious diseases caused by Onchocerca volvulus. This parasite is responsible for chronic cutaneous and ocular diseases affecting more than 37 million people of whom 99% are in Africa. The study was conducted in the health district of Ntui from June to September 2016 to determine the prevalence of O. volvulus infection after seven years of massive administration of ivermectin. Methods two cutaneous snips were made at the iliac crests level in volunteers. These tissues were incubated in physiological saline water and were examined for parasitological investigations in the laboratory. Results a total of 310 participants were randomly selected, of whom 170 (54.8%) were women and 140 (45.1%) were men aged 6 to 83 years, thus giving a sex ratio of 1.2 in favour of women. After parasitological analysis, 26 participants had microfilaraemia, of whom 15 (10.7%) were men and 11 (6.4%) were women. The most infected age group was 16 to 26 years (12.5%). The highest infection rates were found among farmers (11%) and participants living in the village of Essougly (26.6%). No significant differences in prevalence values between the different groups were noted, whatever the parameter considered. Conclusion the prevalence of onchocerciasis in the health district of Ntui has declined from a hyperendemic to a hypoendemic state after seven years of massive administration of ivermectin. However, careful monitoring of onchocerciasis should be continued to prevent the area from returning to its original hyperendemicity.
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Affiliation(s)
| | - Françoise Guemgne Todjom
- Research Unit of Biology and Applied Ecology, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Guy-Armand Gamago
- Faculté des Sciences de la Santé, Université des Montagnes, Bangangté, Cameroon
| | - Josué Wabo Pone
- Faculté des Sciences de la Santé, Université des Montagnes, Bangangté, Cameroon
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11
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In Silico Design and Validation of OvMANE1, a Chimeric Antigen for Human Onchocerciasis Diagnosis. Pathogens 2020; 9:pathogens9060495. [PMID: 32580355 PMCID: PMC7350323 DOI: 10.3390/pathogens9060495] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/12/2020] [Accepted: 06/18/2020] [Indexed: 02/06/2023] Open
Abstract
The public health goal of onchocerciasis in Africa has advanced from control to elimination. In this light, accurate diagnosis is necessary to determine treatment endpoints and confirm elimination, as well as to conduct surveillance for the identification of any possible recrudescence of the disease. Currently, the monitoring of onchocerciasis elimination relies on the Ov-16 test. However, this test is unable to discriminate between past and active infections. Furthermore, about 15-25% of infected persons are reported to be negative for the Ov-16 test, giving a misleading sense of security to false-negative individuals who might continue to serve as reservoirs for infections. Therefore, we opted to design and validate a more sensitive and specific chimeric antigen (OvMANE1) for onchocerciasis diagnosis, using previously reported immunodominant peptides of O. volvulus, the parasite responsible for the disease. In silico analysis of OvMANE1 predicted it to be more antigenic than its individual peptides. We observed that OvMANE1 reacts specifically and differentially with sera from O. volvulus infected and non-infected individuals, as well as with sera from communities of different levels of endemicity. Moreover, we found that total IgG, unlike IgG4 subclass, positively responded to OvMANE1, strongly suggesting its complementarity to the Ov-16 diagnostic tool, which detects Ov-16 IgG4 antibodies. Overall, OvMANE1 exhibited the potential to be utilized in the development of specific diagnostic tools-based on both antibody capture and antigen capture reactions-which are indispensable to monitor the progress of onchocerciasis elimination programs.
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12
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Njume FN, Ghogomu SM, Shey RA, Gainkam LOT, Poelvoorde P, Humblet P, Kamgno J, Robert A, Mutesa L, Lelubre C, Edelweiss E, Poterszman A, Anheuser S, Vanhamme L, Souopgui J. Identification and characterization of the Onchocerca volvulus Excretory Secretory Product Ov28CRP, a putative GM2 activator protein. PLoS Negl Trop Dis 2019; 13:e0007591. [PMID: 31329585 PMCID: PMC6675134 DOI: 10.1371/journal.pntd.0007591] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 08/01/2019] [Accepted: 07/01/2019] [Indexed: 11/18/2022] Open
Abstract
Onchocerca volvulus is the nematode pathogen responsible for human onchocerciasis also known as "River blindness", a neglected tropical disease that affects up to 18 million people worldwide. Helminths Excretory Secretory Products (ESPs) constitute a rich repertoire of molecules that can be exploited for host-parasite relationship, diagnosis and vaccine studies. Here, we report, using a range of molecular techniques including PCR, western blot, recombinant DNA technology, ELISA, high performance thin-layer chromatography and mass spectrometry that the 28 KDa cysteine-rich protein (Ov28CRP) is a reliable component of the O. volvulus ESPs to address the biology of this parasite. We showed that (1) Ov28CRP is a putative ganglioside GM2 Activator Protein (GM2AP) conserved in nematode; (2) OvGM2AP gene is transcriptionally activated in all investigated stages of the parasitic life cycle, including larval and adult stages; (3) The full-length OvGM2AP was detected in in-vitro O. volvulus ESPs of adult and larval stages; (4) the mass expressed and purified recombinant OvGM2AP purified from insect cell culture medium was found to be glycosylated at asparagine 173 and lacked N-terminal signal peptide sequence; (5) the recombinant OvGM2AP discriminated serum samples of infected and uninfected individuals; (6) OvGM2AP competitively inhibits MUG degradation by recombinant β-hexosaminidase A but not MUGS, and could not hydrolyze the GM2 to GM3; (7) humoral immune responses to the recombinant OvGM2AP revealed a negative correlation with ivermectin treatment. Altogether, our findings suggest for the first time that OvGM2AP is an antigenic molecule whose biochemical and immunological features are important to gain more insight into our understanding of host-parasite relationship, as well as its function in parasite development at large.
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Affiliation(s)
- Ferdinand Ngale Njume
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
- Molecular and Cell Biology Laboratory, Biotechnology Unit, University of Buea, Buea, Cameroon
| | - Stephen Mbigha Ghogomu
- Molecular and Cell Biology Laboratory, Biotechnology Unit, University of Buea, Buea, Cameroon
| | - Robert Adamu Shey
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
- Molecular and Cell Biology Laboratory, Biotechnology Unit, University of Buea, Buea, Cameroon
| | - Lea Olive Tchouate Gainkam
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Philippe Poelvoorde
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Perrine Humblet
- École de santé publique, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Joseph Kamgno
- Department of Epidemiology, Centre for research on filariasis and other tropical diseases, Yaounde, Cameroon
| | - Annie Robert
- Faculté de santé publique, Institut de recherche expérimentale et clinique, Pôle d'épidémiologie et biostatistique, Université Catholique de Louvain, Clos Chapelle-aux-champs, Woluwe-Saint-Lambert, Belgium
| | - Leon Mutesa
- Center for Human Genetics, College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda
| | - Christophe Lelubre
- Laboratoire de Médecine Expérimentale, Université Libre de Bruxelles (ULB)—Unité 222, CHU Charleroi (Hôpital André Vésale), Rue de Gozée, Montigny-Le-Tilleul, Belgium
| | - Evelina Edelweiss
- Department of Integrated Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Department of Integrated Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale, UMR7104, Illkirch, France
- Department of Integrated Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, UMR7104, Illkirch, France
| | - Arnaud Poterszman
- Department of Integrated Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Department of Integrated Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale, UMR7104, Illkirch, France
- Department of Integrated Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, UMR7104, Illkirch, France
| | - Susi Anheuser
- LIMES Institute, Membrane Biology & Lipid Biochemistry Unit, c/o Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
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13
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Dissak-Delon FN, Kamga GR, Humblet PC, Robert A, Souopgui J, Kamgno J, Ghogomu SM, Godin I. Barriers to the National Onchocerciasis Control Programme at operational level in Cameroon: a qualitative assessment of stakeholders' views. Parasit Vectors 2019; 12:246. [PMID: 31109348 PMCID: PMC6528230 DOI: 10.1186/s13071-019-3497-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 05/09/2019] [Indexed: 11/16/2022] Open
Abstract
Background The global burden of onchocerciasis is the heaviest in sub-Saharan Africa. Studies have shown the importance of the role of Community-Directed Distributors (CDDs) and nurses in onchocerciasis control, but little is known about their experience in implementing onchocerciasis control programmes. Our aim was to document the barriers that CDDs and local health administrators face in implementing onchocerciasis control activities. Methods We conducted a qualitative survey consisting of 16 in-depth interviews and 8 focus group discussions (FGDs) across three health districts of Cameroon. We interviewed a total of 9 local health officials at the district and Health Area levels, and 7 CDDs. Eight FGDs were conducted with CDDs and Health Committee members. Results The major barriers to the implementation of Community Directed Treatment with Ivermectin that we identified were linked and interrelated. Examples of these barriers included: contextual factors (geographical and cultural background), top-to-bottom planning, insufficient human and material resources, and lack of transparency in the management of the programme’s funds. Conclusions The CDTI at operational level still faces many obstacles which negatively affect therapeutic coverages. This can lead to the non-adhesion of the communities to the programme, consequently jeopardizing the sustainability of the onchocerciasis elimination programme. We recommend that the national programme planners put in place a transparent management and planning system for onchocerciasis elimination activities, with better communication with local programme stakeholders.
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Affiliation(s)
- Fanny Nadia Dissak-Delon
- Ministry of Public Health, N°8, Rue 3038 quartier du Lac, Yaounde, Cameroon. .,Ecole de Santé Publique - Campus Erasme, Université Libre de Bruxelles, Route de Lennik 808 CP591, 1070, Brussels, Belgium. .,Molecular and Cell Biology Laboratory, Department of Biochemistry and Molecular Biology, University of Buea, P.O. Box 63, Buea, Cameroon.
| | - Guy-Roger Kamga
- Ministry of Public Health, N°8, Rue 3038 quartier du Lac, Yaounde, Cameroon.,Molecular and Cell Biology Laboratory, Department of Biochemistry and Molecular Biology, University of Buea, P.O. Box 63, Buea, Cameroon.,Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Clos Chapelle-aux-champs 30 bte B1.30.13, 1200, Brussels, Belgium
| | - Perrine Claire Humblet
- Ecole de Santé Publique - Campus Erasme, Université Libre de Bruxelles, Route de Lennik 808 CP591, 1070, Brussels, Belgium
| | - Annie Robert
- Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Clos Chapelle-aux-champs 30 bte B1.30.13, 1200, Brussels, Belgium
| | - Jacob Souopgui
- Institute of Molecular Biology and Medicine, Université Libre de Bruxelles, Rue des professeurs Jeener et Brachet 12, Gosselies, 6041, Charleroi, Belgium
| | - Joseph Kamgno
- Centre for Research on Filariasis and other Tropical Diseases, P.O. Box 5797, Yaounde, Cameroon.,Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 1364, Yaounde, Cameroon
| | - Stephen Mbigha Ghogomu
- Molecular and Cell Biology Laboratory, Department of Biochemistry and Molecular Biology, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Isabelle Godin
- Ecole de Santé Publique - Campus Erasme, Université Libre de Bruxelles, Route de Lennik 808 CP591, 1070, Brussels, Belgium
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Shey RA, Ghogomu SM, Esoh KK, Nebangwa ND, Shintouo CM, Nongley NF, Asa BF, Ngale FN, Vanhamme L, Souopgui J. In-silico design of a multi-epitope vaccine candidate against onchocerciasis and related filarial diseases. Sci Rep 2019; 9:4409. [PMID: 30867498 PMCID: PMC6416346 DOI: 10.1038/s41598-019-40833-x] [Citation(s) in RCA: 200] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/25/2019] [Indexed: 01/02/2023] Open
Abstract
Onchocerciasis is a parasitic disease with high socio-economic burden particularly in sub-Saharan Africa. The elimination plan for this disease has faced numerous challenges. A multi-epitope prophylactic/therapeutic vaccine targeting the infective L3 and microfilaria stages of the parasite's life cycle would be invaluable to achieve the current elimination goal. There are several observations that make the possibility of developing a vaccine against this disease likely. For example, despite being exposed to high transmission rates of infection, 1 to 5% of people have no clinical manifestations of the disease and are thus considered as putatively immune individuals. An immuno-informatics approach was applied to design a filarial multi-epitope subunit vaccine peptide consisting of linear B-cell and T-cell epitopes of proteins reported to be potential novel vaccine candidates. Conservation of the selected proteins and predicted epitopes in other parasitic nematode species suggests that the generated chimera could be helpful for cross-protection. The 3D structure was predicted, refined, and validated using bioinformatics tools. Protein-protein docking of the chimeric vaccine peptide with the TLR4 protein predicted efficient binding. Immune simulation predicted significantly high levels of IgG1, T-helper, T-cytotoxic cells, INF-γ, and IL-2. Overall, the constructed recombinant putative peptide demonstrated antigenicity superior to current vaccine candidates.
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Affiliation(s)
- Robert Adamu Shey
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium.,Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Stephen Mbigha Ghogomu
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Kevin Kum Esoh
- Department of Biochemistry, Faculty of Science, Jomo Kenyatta University of Agriculture and Technology, Juja, Kenya
| | - Neba Derrick Nebangwa
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Cabirou Mounchili Shintouo
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Nkemngo Francis Nongley
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Bertha Fru Asa
- Department of Public Health and Hygiene, Faculty of Health Science, University of Buea, Buea, Cameroon
| | - Ferdinand Njume Ngale
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium.,Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies, Belgium.
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15
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Bakajika D, Senyonjo L, Enyong P, Oye J, Biholong B, Elhassan E, Boakye D, Dixon R, Schmidt E. On-going transmission of human onchocerciasis in the Massangam health district in the West Region of Cameroon: Better understanding transmission dynamics to inform changes in programmatic interventions. PLoS Negl Trop Dis 2018; 12:e0006904. [PMID: 30427830 PMCID: PMC6261645 DOI: 10.1371/journal.pntd.0006904] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 11/28/2018] [Accepted: 10/06/2018] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Massangam health district (HD), in the West Region of Cameroon, has received ivermectin mass drug administration (MDA) for 20 years, however there is evidence of continued high transmission of Onchocerca volvulus. In order to better understand the transmission dynamics in the HD and inform intervention strategies there is a need to delineate the boundaries of the suspected area of high transmission within the wider transmission zone. METHODOLOGY/PRINCIPAL FINDINGS Parasitological and entomological surveys were conducted to map out the breeding sites of Simulium damnosum and evaluate the prevalence of onchocerciasis in neighbouring communities, including Makouopsap sentinel community. Potential rapids were prospected for identification of S. damnosum larvae and black flies collected to determine infectivity rates. Adults were assessed for the presence of O. volvulus microfilariae through a skin snip biopsy and examined for the presence of nodules. Anti Ov-16 antibodies were tested for in children. Four perennial breeding sites were identified on the Rivers Mbam and Nja. Large number of flies were collected along the River Mbam, especially in the rainy season, with up to 955 flies per day, suggesting this river is a perennial source of black flies. A total of 0.8% of parous flies were infective across the study area. Parasitological studies provided evidence of high rates of infection in the sentinel community and three neighbouring communities, with 37.1% of adults microfilariae positive in Makouopsap. High Ov-16 seropositivity in children also provided evidence of recent on-going transmission. In comparison, communities sampled further away from the sentinel community and neighbouring breeding sites were much closer to reaching onchocerciasis elimination targets. CONCLUSIONS/SIGNIFICANCE This study provides evidence of a particular geographic area of high transmission in an approximate 12 km range around the sentinel community of Makouopsap and the neighbouring breeding sites on the River Nja. To eliminate onchocerciasis by 2025, there is a need to explore alternative intervention strategies in this area of high transmission.
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Affiliation(s)
| | | | | | | | | | | | - Daniel Boakye
- Noguchi Memorial Institute for Medical Research, Accra, Ghana
| | - Ruth Dixon
- Sightsavers, Haywards Heath, United Kingdom
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16
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Shey RA, Ghogomu SM, Njume FN, Gainkam LOT, Poelvoorde P, Mutesa L, Robert A, Humblet P, Munyampundu JP, Kamgno J, Lelubre C, Vanhamme L, Souopgui J. Prediction and validation of the structural features of Ov58GPCR, an immunogenic determinant of Onchocerca volvulus. PLoS One 2018; 13:e0202915. [PMID: 30256790 PMCID: PMC6157839 DOI: 10.1371/journal.pone.0202915] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 08/11/2018] [Indexed: 11/18/2022] Open
Abstract
Onchocerciasis is a severely debilitating yet neglected tropical disease (NTD) that creates social stigma, generates and perpetuates poverty, and leads ultimately in some cases to irreversible unilateral or bilateral blindness if untreated. Consequently, the disease is a major impediment to socioeconomic development. Many control programs have been launched for the disease with moderate successes achieved. This mitigated hit is partially due to the lingering need for reliable, non-invasive and easily applicable tools for mapping endemic regions and post-elimination surveillance. In this work, bioinformatics analyses combined with immunological assays were applied in a bid to develop potential tools for diagnosis and assessing the success of drug treatment programs. We report that (i) the O. volvulus antigen, Ov58GPCR is a G-protein coupled receptor (GPCR) conserved in related nematodes, (ii) synthetic peptides predicted to be in the extracellular domain (ECD) of Ov58GPCR are indeed immunogenic epitopes in actively-infected individuals, (iii) synthetic peptide cocktails discriminate between actively-infected individuals, treated individuals and healthy African controls, (iv) polyclonal antibodies against one of the peptides or against the bacterially-expressed ECD reacted specifically with the native antigen of O. volvulus total and surface extracts, (v) Ov58GPCR is transcribed in both larvae and adult parasite stages, (vi) IgG and IgE responses to the recombinant ECD decline with ivermectin treatment. All these findings suggest that the extracellular domain and synthetic peptides of Ov58GPCR, as well as the specific immune response generated could be harnessed in the context of disease diagnosis and surveillance.
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Affiliation(s)
- Robert Adamu Shey
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM Universite Libre de Bruxelles, Gosselies Campus, Gosselies, Hainaut, Belgium
- Molecular and Cell Biology Laboratory, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Stephen Mbigha Ghogomu
- Molecular and Cell Biology Laboratory, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Ferdinand Ngale Njume
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM Universite Libre de Bruxelles, Gosselies Campus, Gosselies, Hainaut, Belgium
- Molecular and Cell Biology Laboratory, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Lea Olive Tchouate Gainkam
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM Universite Libre de Bruxelles, Gosselies Campus, Gosselies, Hainaut, Belgium
| | - Philippe Poelvoorde
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM Universite Libre de Bruxelles, Gosselies Campus, Gosselies, Hainaut, Belgium
| | - Leon Mutesa
- Center for Human Genetics, College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda
| | - Annie Robert
- Faculté de santé publique, Institut de recherche expérimentale et clinique, Pôle d'épidémiologie et biostatistique, Université Catholique de Louvain, Clos Chapelle-aux-champs, Woluwe-Saint-Lambert, Belgium
| | - Perrine Humblet
- École de santé publique, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Jean-Pierre Munyampundu
- Center for Human Genetics, College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda
| | - Joseph Kamgno
- Department of Epidemiology, Centre for research on filariasis and other tropical diseases, (CRFilMT), Yaoundé, Cameroon
| | - Christophe Lelubre
- Laboratoire de Médecine Expérimentale, Université Libre de Bruxelles (ULB) - Unité 222, CHU Charleroi (Hôpital André Vésale), Montigny-Le-Tilleul, Belgium
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM Universite Libre de Bruxelles, Gosselies Campus, Gosselies, Hainaut, Belgium
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM Universite Libre de Bruxelles, Gosselies Campus, Gosselies, Hainaut, Belgium
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17
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Murdoch ME. Onchodermatitis: Where Are We Now? Trop Med Infect Dis 2018; 3:E94. [PMID: 30274490 PMCID: PMC6160948 DOI: 10.3390/tropicalmed3030094] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/27/2018] [Accepted: 08/28/2018] [Indexed: 02/07/2023] Open
Abstract
Onchocerciasis causes debilitating pruritus and rashes as well as visual impairment and blindness. Prior to control measures, eye disease was particularly prominent in savanna areas of sub-Saharan Africa whilst skin disease was more common across rainforest regions of tropical Africa. Mass drug distribution with ivermectin is changing the global scene of onchocerciasis. There has been successful progressive elimination in Central and Southern American countries and the World Health Organization has set a target for elimination in Africa of 2025. This literature review was conducted to examine progress regarding onchocercal skin disease. PubMed searches were performed using keywords 'onchocerciasis', 'onchodermatitis' and 'onchocercal skin disease' over the past eight years. Articles in English, or with an English abstract, were assessed for relevance, including any pertinent references within the articles. Recent progress in awareness of, understanding and treatment of onchocercal skin disease is reviewed with particular emphasis on publications within the past five years. The global burden of onchodermatitis is progressively reducing and is no longer seen in children in many formerly endemic foci.
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Affiliation(s)
- Michele E Murdoch
- Department of Dermatology, West Herts Hospitals NHS Trust, Vicarage Road, Watford, Hertfordshire WD18 0HB, UK.
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18
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Kamga GR, Dissak-Delon FN, Nana-Djeunga HC, Biholong BD, Ghogomu SM, Souopgui J, Kamgno J, Robert A. Audit of the community-directed treatment with ivermectin (CDTI) for onchocerciasis and factors associated with adherence in three regions of Cameroon. Parasit Vectors 2018; 11:356. [PMID: 29921312 PMCID: PMC6009063 DOI: 10.1186/s13071-018-2944-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 06/07/2018] [Indexed: 11/23/2022] Open
Abstract
Background After more than 15 years of community-directed treatment with ivermectin (CDTI) in the Centre 1, Littoral 2 and West CDTI projects in Cameroon, the epidemiological evaluation conducted in 2011 revealed that onchocerciasis endemicity was still high in some communities. To investigate the potential reasons explaining this high endemicity, a cluster coverage survey was conducted in April-May 2015 in three health districts (HD), to assess the implementation of the CDTI, the 2014 therapeutic coverage and the five-year adherence to treatment. A two-stage cluster design was considered during analyses, with data weighted proportionally to age and gender distribution in the population. Results In the three HDs, 69 community leaders, 762 heads of households, 83 community drug distributors (CDD) and 2942 household members were interviewed. The CDTI organization and the involvement of heads of households were in average weak, with 84.0% (95% CI: 81.2–86.4%) of them who had not participated in activities during the 2014 mass drug administration (MDA). On average, six of ten community leaders declared that the period of treatment was decided by the health personnel while the CDDs selection was made during a community meeting for only 43.4% of them. The 2014 weighted therapeutic coverage was 64.1% (95% CI: 56.8–70.9%), with no significant difference in the three HDs. The survey coverages were lower than the reported coverages with a significant difference varying from 14.1% to 22.0%. Among those aged 10 years and above, 57.8% (95% CI: 50.2–65.1%) declared having taken the treatment each time during the last five MDAs with no significant difference among HDs, while 9.8% (95% CI: 7.5–12.8%) declared that they had never taken the drug. In multivariate analysis, the most important factors associated with the five-year adherence to treatment were high involvement in CDTI and age (40+ years). Conclusions Despite more than 15 years of CDTI, there was still weak community participation and ownership, a lower coverage than reported and an average five-year adherence in the surveyed HDs. The reinforcement of the community ownership by the Ministry of Public Health officials and the timely procurement of ivermectin as requested by the communities are some measures that should be implemented to improve the therapeutic coverage, adherence to treatment and hence achieve onchocerciasis elimination. Further anthropological and entomological studies would provide better insights into our understanding of the persistence of the disease in these three CDTI projects.
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Affiliation(s)
- Guy-Roger Kamga
- Ministry of Public Health, N°8, Rue 3038 quartier du Lac, Yaoundé, Cameroon. .,Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), P.O. Box 5797, Yaoundé, Cameroon. .,Institut de Recherche Expérimentale et Clinique, Faculté de santé publique, Université catholique de Louvain, Clos Chapelle-aux-champs 30 bte B1.30.13, BE-1200, Brussels, Belgium.
| | - Fanny N Dissak-Delon
- Ministry of Public Health, N°8, Rue 3038 quartier du Lac, Yaoundé, Cameroon.,Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), P.O. Box 5797, Yaoundé, Cameroon.,Institute of Biology of Molecular Medicine, Rue des professeurs Jeener et Brachet 12 BE-6041 Gosselies, Université Libre de Bruxelles, Brussels, Belgium
| | - Hugues C Nana-Djeunga
- Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), P.O. Box 5797, Yaoundé, Cameroon.,Parasitology and Ecology Laboratory, Faculty of Science, University of Yaoundé 1, PO, Box 812, Yaoundé, Cameroon
| | | | - Stephen Mbigha Ghogomu
- Molecular and Cell Biology Laboratory, Department of Biochemistry and Molecular Biology, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Jacob Souopgui
- Institute of Biology of Molecular Medicine, Rue des professeurs Jeener et Brachet 12 BE-6041 Gosselies, Université Libre de Bruxelles, Brussels, Belgium
| | - Joseph Kamgno
- Centre for Research on Filariasis and other Tropical Diseases (CRFilMT), P.O. Box 5797, Yaoundé, Cameroon.,Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 1364, Yaoundé, Cameroon
| | - Annie Robert
- Institut de Recherche Expérimentale et Clinique, Faculté de santé publique, Université catholique de Louvain, Clos Chapelle-aux-champs 30 bte B1.30.13, BE-1200, Brussels, Belgium
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