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Chikezie FM, Veriegh FBD, Armoo S, Boakye DA, Taylor M, Osei-Atweneboana MY. Ongoing transmission of onchocerciasis in the Pru District of Ghana after two decades of mass drug administration with ivermectin and comparative identification of members of the Simulium damnosum complex using cytological and morphological techniques. Parasit Vectors 2024; 17:394. [PMID: 39289756 PMCID: PMC11409746 DOI: 10.1186/s13071-024-06333-2] [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: 01/18/2024] [Accepted: 05/28/2024] [Indexed: 09/19/2024] Open
Abstract
BACKGROUND Human onchocerciasis remains a public health problem in Ghana. Mass drug administration (MDA) with ivermectin (IVM) has reduced disease morbidity and prevalence, but the transmission of onchocerciasis remains ongoing in several endemic foci. We investigated parasite transmission in some endemic communities in Ghana that had received > 18 rounds of annual MDA with IVM and determined the species composition of black fly (Simulium damnosum) vectors in these areas. METHODS Adult female black flies were collected using human landing catches and identified as either forest or savanna species using morpho-taxonomic keys. The adult flies underwent dissection to determine their parity and detect any O. volvulus larvae, followed by the calculation of entomological indices. Simulium damnosum s.l. larvae were collected and preserved in freshly prepared Carnoy's fixative and were later used for cytotaxonomic studies. RESULTS A total of 9,983 adult flies were caught: 6,569 and 3,414 in the rainy and dry seasons respectively. Black fly biting activities over the study period showed bimodal or trimodal patterns. The highest monthly biting rate (MBR) of 10,578.75 bites/person/month was recorded in July in Beposo, while the highest monthly transmission potential of 100.69 infective bites/person/month was recorded in Asubende in August. Morphological analysis of 2,032 flies showed that 99.8% (2,028) of the flies were savanna species, with only 4 (0.2%) adult flies being of the forest species. Cytogenetic studies on 114 black fly larvae revealed three cytospecies (Simulium damnosum s.s., S. sirbanum and S. sanctipauli) in the study area. CONCLUSIONS The present studies confirmed an ongoing transmission of onchocerciasis in the study communities except Abua-1. It also provides further information on biting behaviors and onchocerciasis transmission indices in the study communities. Further, our data confirmed the savanna species (S. damnosum s.s. and S. sirbanum) of the S. damnosum s.l. to be the major vectors of onchocerciasis in the study areas, with only an occasional influx of forest cytotypes.
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Affiliation(s)
- Friday Maduka Chikezie
- Department of Animal and Environmental Biology, University of Uyo, Uyo, Akwa Ibom State, Nigeria
- African Regional Postgraduate Program in Insect Science, University of Ghana, Legon, Accra, Ghana
| | - Francis Balunnaa Dhari Veriegh
- Biomedical and Public Health Research Unit, Water Research Institute, Council for Scientific and Industrial Research (CSIR), Accra, Ghana
- University of Energy and Natural Resources, Sunyani, Ghana
| | - Samuel Armoo
- Biomedical and Public Health Research Unit, Water Research Institute, Council for Scientific and Industrial Research (CSIR), Accra, Ghana
| | - Daniel Adjei Boakye
- The END (Ending Neglected Diseases) Fund, New York, NY, USA
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra, Ghana
| | - Mark Taylor
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - Mike Yaw Osei-Atweneboana
- Biomedical and Public Health Research Unit, Water Research Institute, Council for Scientific and Industrial Research (CSIR), Accra, Ghana.
- College of Science and Technology, Council for Scientific and Industrial Research (CSIR), Accra, Ghana.
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Siewe Fodjo JN, Ekome SRE, Njamnshi JNT, Njamnshi WY, Njamnshi KG, Ngarka L, Njamnshi AK. Community Perceptions of Blackfly Nuisance and Acceptability of the "Slash and Clear" Vector Control Approach in the Ntui Health District of Cameroon: A Qualitative Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2024; 21:658. [PMID: 38928904 PMCID: PMC11204025 DOI: 10.3390/ijerph21060658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 05/15/2024] [Accepted: 05/19/2024] [Indexed: 06/28/2024]
Abstract
Besides being vectors of the onchocerciasis parasite, blackflies are a source of nuisance in onchocerciasis-endemic communities. We investigated the experience of residents in the Ntui Health District (Cameroon) regarding blackfly nuisance and assessed their perceptions of a novel "Slash and Clear" (S&C) intervention for blackfly control. Focus group discussions were conducted before and after S&C implementation (respectively, in February 2022 and December 2023). Blackflies were known to emerge from the river areas and cause disease. To prevent blackfly bites, the population often covered their body with protective clothing and applied various substances (kerosene, oil, or lemon) to their skin. Post-intervention data showed reduced blackfly nuisance, and the willingness to sustain blackfly control in the long-term was unanimous among community leaders and members, including the village volunteers who implemented the S&C intervention. In conclusion, blackfly nuisance is evident in the Ntui onchocerciasis focus of Cameroon and led to a panoply of coping practices, some of which could be detrimental to their health. Implementing S&C for blackfly control is well accepted and could sustainably alleviate the nuisance caused by blackflies while simultaneously breaking the onchocerciasis transmission cycle.
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Affiliation(s)
- Joseph Nelson Siewe Fodjo
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
- Global Health Institute, University of Antwerp, Doornstraat 331, 2610 Antwerp, Belgium
| | - Serge Raoul Ekukole Ekome
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
| | - Julius Ndi Taryunyu Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
| | - Wepnyu Yembe Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
- Division of Operational Research in Health, Ministry of Public Health, N°8 Rue 3038 quartier du Lac (Yaoundé III), Yaoundé P.O. Box 3595, Cameroon
| | - Kongnyu G. Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
| | - Leonard Ngarka
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
- Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé 1, Yaoundé P.O. Box 1364, Cameroon
- Neurology & Clinical Neuroscience Department, Yaoundé Central Hospital, Yaoundé P.O. Box 87, Cameroon
| | - Alfred K. Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé P.O. Box 25625, Cameroon; (S.R.E.E.); (J.N.T.N.); (W.Y.N.); (K.G.N.); (L.N.)
- Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé 1, Yaoundé P.O. Box 1364, Cameroon
- Neurology & Clinical Neuroscience Department, Yaoundé Central Hospital, Yaoundé P.O. Box 87, Cameroon
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Chunda VC, Fombad FF, Kien CA, Ebai R, Esofi F, Ntuh AN, Ouam E, Gandjui NVT, Ekanya R, Nietcho F, Nchang LC, Magha C, Njouendou AJ, Enyong P, Hoerauf A, Wanji S, Ritter M. Comparative development of human filariae Loa loa, Onchocerca volvulus and Mansonella perstans in immunocompromised mouse strains. FRONTIERS IN TROPICAL DISEASES 2024; 5:1293632. [PMID: 38655273 PMCID: PMC7615855 DOI: 10.3389/fitd.2024.1293632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024] Open
Abstract
Introduction Mouse models of human filarial infections are not only urgently needed to investigate the biology of the nematodes and their modulation of the host's immunity, but will also provide a platform to screen and test novel anti-filarial drugs. Recently, murine Loa loa infection models have been stablished using immunocompromised mouse strains, whereas murine Mansonella perstans infections have not been implemented until now. Methods Therefore, we aim to establish experimental M. perstans infections using the immunocompromised mouse strains RAG2IL-2Rγ-/- (lack B, T and natural killer cells), IL-4Rα/IL-5-/- (impaired IL-4/5 signalling and eosinophil activation) and NOD.Cg-PrkdcscidIl2rgtm1Wj l/SzJ (NOD scid gamma, NSG) BALB/c mice (lack mature lymphocytes) through subcutaneous (s.c.) or intraperitoneal (i.p.) inoculation of infective stage 3 larvae (L3) isolated from engorged vectors. Results In total, 145 immunocompromised mice have been inoculated with 3,250 M. perstans, 3,337 O. volvulus, and 2,720 Loa loa L3 to comparatively analyse which immunocompromised mouse strain is susceptible to human filarial infections. Whereas, no M. perstans and O. volvulus L3 could be recovered upon 2-63 days post-inoculation, a 62-66% Loa loa L3 recovery rate could be achieved in the different mouse strains. Gender of mice, type of inoculation (s.c. or i.p.) or time point of analysis (2-63 days post inoculation) did not interfere with the success of L3 recovery. In addition, administration of the immune suppressants hydrocortisone, prednisolone and cyclophosphamide did not restore M. perstans L3 recovery rates. Discussion These findings show that RAG2IL-2Rg-/-BALB/c and C57BL/6, IL-4Rα/IL-5-/- BALB/c and NSG mice were not susceptible to M. perstans and O. volvulus L3 inoculation using the applied methods, whereas Loa loa infection could be maintained. Further studies should investigate if humanized immunocompromised mice might be susceptible to M. perstans. and O. volvulus.
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Affiliation(s)
- Valerine C. Chunda
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Fanny Fri Fombad
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Chi Anizette Kien
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Rene Ebai
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Frederick Esofi
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Anna Ning Ntuh
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Emmanuel Ouam
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Narcisse Victor Tchamatchoua Gandjui
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Relindis Ekanya
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Franck Nietcho
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Lucy Cho Nchang
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Chefor Magha
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Abdel Jelil Njouendou
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Peter Enyong
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Achim Hoerauf
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
- German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
- German-West African Centre for Global Health and Pandemic Prevention (G-WAC), Partner Site Bonn, Bonn, Germany
| | - Samuel Wanji
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Manuel Ritter
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
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Domche A, Nana Djeunga HC, Nwane PB, Njitchouang GR, Nono Fesuh B, Njiokou F, Jacob B, Pion SD, Kamgno J. Significant reduction of blackfly densities in persistent onchocerciasis area following pilot implementation of an environment friendly approach (Slash and Clear). Sci Rep 2024; 14:408. [PMID: 38172522 PMCID: PMC10764779 DOI: 10.1038/s41598-023-50747-4] [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: 07/10/2023] [Accepted: 12/24/2023] [Indexed: 01/05/2024] Open
Abstract
The effectiveness of the "Slash and Clear" method in reducing blackfly populations in low transmission areas is established, but its impact in high transmission settings with large rivers and dense vectors is yet to be proven. A community-based intervention study was conducted in the Mbam Valley, Centre Cameroon, involving two sites: Bayomen (control) and Biatsota (intervention). In each arm, baseline blackfly densities were collected over one year using the human landing method. The intervention consisted of destroying the trailing vegetation where blackflies breed. Blackfly densities were collected post-intervention to assess the impact of the intervention. Post-intervention data showed a 50.8% reduction in blackfly density in Biatsota (mean number of collected blackflies from 1936 to 953), while a reduction of 26.7% was observed in Bayomen (mean number of collected blackflies from 2418 to 1774). The reduction rate attributable to the intervention was 32.9%. Statistical analysis confirmed that the reduction in blackfly density was significantly greater in the intervention site. This study demonstrates the feasibility and significant impact of the "Slash and Clear" method in high transmission areas. However, further research is required to assess its long-term effects and determine how this strategy can be scaled up and sustained until onchocerciasis elimination is achieved.
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Affiliation(s)
- André Domche
- Higher Institute of Scientific and Medical Research (ISM), Yaoundé, Cameroon.
- Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon.
| | | | - Philippe B Nwane
- Higher Institute of Scientific and Medical Research (ISM), Yaoundé, Cameroon
- Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon
| | - Guy R Njitchouang
- Higher Institute of Scientific and Medical Research (ISM), Yaoundé, Cameroon
| | - Betrand Nono Fesuh
- Higher Institute of Scientific and Medical Research (ISM), Yaoundé, Cameroon
| | - Flobert Njiokou
- Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon
| | - Benjamin Jacob
- Department of Global Health, College of Public Health, University of South Florida, Tampa, FL, USA
| | - Sébastien D Pion
- UMI 233 TransVIH MI, University of Montpellier, Institut de Recherche pour le Développement (IRD), Institut National de la Santé et de la Recherche Médicale (INSERM), Montpellier, France
| | - Joseph Kamgno
- Higher Institute of Scientific and Medical Research (ISM), Yaoundé, Cameroon
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Otabil KB, Basáñez MG, Ankrah B, Opoku SA, Kyei DO, Hagan R, Ababio R, Bart-Plange EJ, Babae TN, Kudzordzi PC, Darko VA, Bamfo JG, Ameyaw J, Raji AS, Hadermann A, Schallig HDFH, Colebunders R. Persistence of onchocerciasis and associated dermatologic and ophthalmic pathologies after 27 years of ivermectin mass drug administration in the middle belt of Ghana. Trop Med Int Health 2023; 28:844-854. [PMID: 37846505 DOI: 10.1111/tmi.13937] [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] [Indexed: 10/18/2023]
Abstract
OBJECTIVES There is a pressing need to regularly evaluate the progress of onchocerciasis elimination programmes to timely identify and mitigate potential risks hindering the reaching of the 2030 targets proposed by the World Health Organization (WHO) in its roadmap on neglected tropical diseases (NTDs). We determined the prevalence of onchocerciasis and associated dermatological and ophthalmological manifestations in six endemic communities in the Bono Region of Ghana after 27 years of ivermectin mass treatment. METHODS In a cross-sectional study, 564 participants aged ≥5 years were enrolled (49.1% females), with a median age of 26 (range: 5-89) years. In 54% and 47%, skin-snip microscopy and Ov16 rapid diagnostic tests were performed, respectively. Skin disease was determined using the WHO Skin NTD App. Visual function assessments included tests of visual acuity. RESULTS The overall microfilarial prevalence was 12.5% (38/305) and Ov16 seroprevalence was 24.2% (64/265). Severe itching was recorded in 24.3%, acute papular onchodermatitis in 52.8%, chronic papular onchodermatitis in 12.5%, lichenified onchodermatitis in 0.7%, skin atrophy in 11.3%, depigmentation in 1.7% and palpable nodules in 5.3%. Of the 301 persons in which visual acuity was examined, 17% were visually impaired and 5.3% were blind and 47.3% presented with cataract. Chronic papular onchodermatitis, lichenified onchodermatitis, depigmentation and visual impairment were significantly associated with the presence of skin microfilariae and Ov16 seropositivity. CONCLUSIONS The persistence of Onchocerca volvulus infection and onchocerciasis-associated dermatological and ophthalmological pathologies after prolonged treatment is of concern. There is a need to include morbidity management in onchocerciasis elimination programmes and understand better patterns of treatment coverage, adherence and actual intake of ivermectin.
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Affiliation(s)
- Kenneth Bentum Otabil
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
- Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
- Global Health Institute, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - María-Gloria Basáñez
- Department of Infectious Disease Epidemiology, MRC Centre for Global Infectious Disease Analysis (MRC GIDA), and London Centre for Neglected Tropical Disease Research, School of Public Health, Imperial College London, London, UK
| | - Blessing Ankrah
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Stephen Agyemang Opoku
- Department of Medical Laboratory Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Dennis Ofori Kyei
- Department of Medical Laboratory Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Rhoda Hagan
- Department of Medical Laboratory Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Richmond Ababio
- Department of Medical Laboratory Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Emmanuel John Bart-Plange
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Theophilus Nti Babae
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Prince-Charles Kudzordzi
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Vera Achiaa Darko
- Consortium for Neglected Tropical Diseases and One Health, Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
- STU Clinic, Sunyani Technical University, Sunyani, Bono Region, Ghana
| | | | | | - Abdul Sakibu Raji
- Department of Biological Science, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana
| | - Amber Hadermann
- Global Health Institute, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Henk D F H Schallig
- Department of Medical Microbiology, Experimental Parasitology Unit, Amsterdam University Medical Centres, Academic Medical Centre at the University of Amsterdam, Amsterdam, The Netherlands
| | - Robert Colebunders
- Global Health Institute, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
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Yotsu RR, Fuller LC, Murdoch ME, Revankar C, Barogui YT, Pemmaraju VRR, Ruiz-Postigo JA, Dagne DA, Asiedu K, Hay RJ. World Health Organization strategic framework for integrated control and management of skin-related neglected tropical diseases: what does this mean for dermatologists? Br J Dermatol 2023; 188:157-159. [PMID: 36630642 DOI: 10.1093/bjd/ljac031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 09/17/2022] [Indexed: 01/13/2023]
Abstract
Skin-related neglected tropical diseases, or skin NTDs, comprise a group of NTDs that produce signs and symptoms on the skin, and includes at least nine diseases and disease groups. The World Health Organization launched the ‘Ending the neglect to attain the Sustainable Development Goals: a strategic framework for integrated control and management of skin-related neglected tropical diseases’ in June 2022, which this article summarises and sets out the way forward including guidance on how dermatologists and dermatological communities along with public health communities may support this initiative to contribute towards achieving skin care for everyone everywhere.
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Affiliation(s)
- Rie R Yotsu
- Tulane School of Public Health and Tropical Medicine, New Orleans, LA, USA.,School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan.,Department of Dermatology, National Center for Global Health and Medicine, Tokyo, Japan
| | - L Claire Fuller
- International Foundation for Dermatology, London, UK.,Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
| | - Michele E Murdoch
- Department of Dermatology, West Herts Teaching Hospitals NHS Trust, Watford General Hospital, Watford, UK
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Siewe Fodjo JN, Ngarka L, Njamnshi WY, Enyong PA, Zoung-Kanyi Bissek AC, Njamnshi AK. Onchocerciasis in the Ntui Health District of Cameroon: epidemiological, entomological and parasitological findings in relation to elimination prospects. Parasit Vectors 2022; 15:444. [PMID: 36443885 PMCID: PMC9702945 DOI: 10.1186/s13071-022-05585-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 09/20/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Despite decades of community-directed treatment with ivermectin (CDTI), onchocerciasis transmission persists in Cameroon and has been associated with increased risk for epilepsy in endemic communities. We investigated the onchocerciasis situation in the Ntui Health District (a known onchocerciasis focus in Cameroon where the Sanaga River constitutes the main source of black fly vectors) using parasitological, entomological and serological parameters. METHODS In July 2021, community-based surveys were conducted in four villages (Essougli, Nachtigal, Ndjame and Ndowe). Onchocerciasis was diagnosed via microscopic examination of skin snips. Using rapid diagnostic tests, we screened children aged 3-6 years for Ov16 antibodies as a proxy for recent onchocerciasis transmission. Monthly black fly biting rates were obtained from the two riverside villages (Nachtigal and Essougli) for 12 consecutive months (July 2021 to June 2022) using the human landing catch technique. Some black flies were dissected each month to check for infection. RESULTS Overall, 460 participants were recruited; mean age was 32.1 (range: 3-85) years with 248 (53.9%) being males. Among skin snipped participants (n = 425), onchocerciasis prevalence was 14.6%. Participants with epilepsy (n = 25) were more often skin snip positive (45.8% vs 12.7%; P < 0.001) and had higher microfilarial loads (9.2 ± 22.0 vs 0.7 ± 3.5 microfilariae/skin snip; P < 0.001) compared to their peers without epilepsy. Eight (6.5%) of the 123 tested children were Ov16 seropositive. The breeding sites we investigated along the Sanaga River during the current study harbored fewer vectors (annual biting rates reaching 530,322 vs 606,370 in the Mbam River) and exhibited lower black fly infection rates (annual transmission potentials reaching 1479 vs 4488 in the Mbam River) when compared to recent entomological reports in Cameroon. CONCLUSION Despite substantial biting rates, black fly infection rates (by microscopy) in the Ntui Health District were rather low resulting in overall low transmission potentials in study villages. Thanks to CDTI, O. volvulus infection in both humans and insects is on the decrease. However, there is evidence that O. volvulus is still endemic in these communities. Reducing the vector population will further accelerate onchocerciasis elimination prospects.
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Affiliation(s)
- Joseph Nelson Siewe Fodjo
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
- Neurology Department, Central Hospital Yaoundé, Yaoundé, Cameroon
| | - 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
| | - 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
- Ministry of Public Health, Division of Health Operations Research, Yaoundé, Cameroon
| | - Peter Ayuk Enyong
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Anne-Cécile Zoung-Kanyi Bissek
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
- Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
- Ministry of Public Health, Division of Health Operations Research, Yaoundé, Cameroon
| | - Alfred Kongnyu 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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8
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Borlase A, Le Rutte EA, Castaño S, Blok DJ, Toor J, Giardina F, Davis EL. Evaluating and mitigating the potential indirect effect of COVID-19 on control programmes for seven neglected tropical diseases: a modelling study. Lancet Glob Health 2022; 10:e1600-e1611. [PMID: 36240827 PMCID: PMC9579354 DOI: 10.1016/s2214-109x(22)00360-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/25/2022] [Accepted: 08/03/2022] [Indexed: 11/06/2022]
Abstract
Background In line with movement restrictions and physical distancing essential for the control of the COVID-19 pandemic, WHO recommended postponement of all neglected tropical disease (NTD) control activities that involve community-based surveys, active case finding, and mass drug administration in April, 2020. Following revised guidance later in 2020, and after interruptions to NTD programmes of varying lengths, NTD programmes gradually restarted in the context of an ongoing pandemic. However, ongoing challenges and service gaps have been reported. This study aimed to evaluate the potential effect of the programmatic interruptions and strategies to mitigate this effect. Methods For seven NTDs, namely soil-transmitted helminths, schistosomiasis, lymphatic filariasis, onchocerciasis, trachoma, visceral leishmaniasis, and human African trypanosomiasis, we used mathematical transmission models to simulate the effect of programme interruptions on the dynamics of each of these diseases in different endemic settings. We also explored the potential benefit of implementing mitigation strategies, primarily in terms of minimising the delays to control targets. Findings We show that the effect of the COVID-19-induced interruption in terms of delay to achieving elimination goals might in some cases be much longer than the duration of the interruption. For schistosomiasis, onchocerciasis, trachoma, and visceral leishmaniasis, a mean delay of 2–3 years for a 1-year interruption is predicted in areas of highest prevalence. We also show that these delays can largely be mitigated by measures such as additional mass drug administration or enhanced case-finding. Interpretation The COVID-19 pandemic has brought infectious disease control to the forefront of global consciousness. It is essential that the NTDs, so long neglected in terms of research and financial support, are not overlooked, and remain a priority in health service planning and funding. Funding Bill & Melinda Gates Foundation, Medical Research Council, and the UK Foreign, Commonwealth & Development Office.
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Affiliation(s)
- Anna Borlase
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
| | - Epke A Le Rutte
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands; Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Soledad Castaño
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland; LYO-X, Allschwil, Switzerland
| | - David J Blok
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Jaspreet Toor
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK; MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - Federica Giardina
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands; Department of Health Evidence, Radboud University Medical Center, Nijmegen, Netherlands
| | - Emma L Davis
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK; Mathematics Institute, University of Warwick, Coventry, UK.
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9
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Ju T, Vander Does A, Ingrasci G, Norton SA, Yosipovitch G. Tropical parasitic itch in returned travellers and immigrants from endemic areas. J Eur Acad Dermatol Venereol 2022; 36:2279-2290. [PMID: 35793476 DOI: 10.1111/jdv.18408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 06/15/2022] [Indexed: 11/30/2022]
Abstract
Itch is the most common skin symptom among tropical parasitic diseases (TPD), but there are limited data about its characteristics in these conditions. In dermatology practices and travellers' health clinics in the developed world, itch is a common complaint among travellers returning from endemic areas, as well among migrants arriving from endemic areas, where they may have been exposed to TPD. Studying aspects of pruritus among TPD may lead to improvements in prompt, accurate diagnosis and management of these conditions. This review examines the major itch-inducing TPDs, including schistosomiasis, echinococcosis, onchocerciasis, scabies, cutaneous larva migrans, larva currens, African trypanosomiasis, dracunculiasis and other causes of travel associated pruritus. We focus on the link between pruritus and other symptoms, aetiology, clinical staging and therapeutic options for these parasitic illnesses. Because some tropical parasitic diseases can present with significant pruritus, we attempt to identify aspects of the pruritus that are characteristic of-or unique to-specific conditions. These diagnostic insights may help clinicians create a rational and focused differential diagnosis and help determine optimal disease management pathways. In this sense, management involves treating the individual, seeking epidemiologically linked cases, preventing recurrences or relapses, and reducing spread of the disease.
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Affiliation(s)
- T Ju
- Dr Phillip Frost Department of Dermatology and Miami Itch Center, University of Miami, Miami, FL, USA
| | - A Vander Does
- Dr Phillip Frost Department of Dermatology and Miami Itch Center, University of Miami, Miami, FL, USA
| | - G Ingrasci
- Dr Phillip Frost Department of Dermatology and Miami Itch Center, University of Miami, Miami, FL, USA
| | - S A Norton
- Department of Dermatology and Pediatrics, George Washington University, Washington, DC, USA
| | - G Yosipovitch
- Dr Phillip Frost Department of Dermatology and Miami Itch Center, University of Miami, Miami, FL, USA
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10
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Prasad S, Bassett IV, Freeman EE. Dermatology on the global stage: The role of dermatologists in international health advocacy and COVID-19 research. Int J Womens Dermatol 2021; 7:653-659. [PMID: 34722850 PMCID: PMC8539819 DOI: 10.1016/j.ijwd.2021.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Over the last decade, there has been a surge in interest and funding for global health dermatology. Skin conditions are now recognized as the fourth leading cause of nonfatal disease burden worldwide in disability-adjusted life years. Dermatologists are uniquely positioned within global health because skin conditions are often the presenting sign of severe illnesses, such as neglected tropical diseases and COVID-19. METHODS We review four major areas of work by dermatologists within global health: i) characterization of global burden of skin disease, ii) advocacy for dermatologic therapies on the World Health Organization's Model List of Essential Medicines, iii) advancements in global programming for skin-related tropical diseases, and iv) the role of dermatologists during the COVID-19 pandemic. For each area of work, the significance and impact on the health of women and girls is briefly highlighted. RESULTS Dermatologists have led the efforts to quantify and evaluate the global burden of skin disease, the burden of which is disproportionately shared by women. The dermatology community has also championed global efforts to eliminate skin-related neglected tropical diseases, such as scabies. Through national and international policy advocacy, dermatologists have pushed for more dermatologic therapies in the World Health Organization's Model List of Essential Medicines, helping to secure better care for patients with skin disease throughout the world. Since 2020, the dermatology community has worked collaboratively in the fight against COVID-19, establishing a worldwide registry for cutaneous manifestations of SARS-CoV-2 and pursuing research that has allowed colleagues in the house of medicine to better understand this landmark disease. CONCLUSION Through the study and promotion of global health, dermatologists have an important role in the house of medicine.
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Affiliation(s)
- Sonya Prasad
- Icahn School of Medicine, The Mount Sinai Hospital, New York, New York
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
| | - Ingrid V. Bassett
- Medical Practice Evaluation Center, Mongan Institute, Massachusetts General Hospital, Boston, Massachusetts
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts
| | - Esther E. Freeman
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
- Medical Practice Evaluation Center, Mongan Institute, Massachusetts General Hospital, Boston, Massachusetts
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11
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Forrer A, Wanji S, Obie ED, Nji TM, Hamill L, Ozano K, Piotrowski H, Dean L, Njouendou AJ, Ekanya R, Ndongmo WPC, Fung EG, Nnamdi DB, Abong RA, Beng AA, Eyong ME, Ndzeshang BL, Nkimbeng DA, Teghen S, Suireng A, Ashu EE, Kah E, Murdoch MM, Thomson R, Theobald S, Enyong P, Turner JD, Taylor MJ. Why onchocerciasis transmission persists after 15 annual ivermectin mass drug administrations in South-West Cameroon. BMJ Glob Health 2021; 6:bmjgh-2020-003248. [PMID: 33431378 PMCID: PMC7802695 DOI: 10.1136/bmjgh-2020-003248] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 11/11/2020] [Accepted: 11/27/2020] [Indexed: 12/11/2022] Open
Abstract
Introduction Onchocerciasis is targeted for elimination mainly with annual community-directed treatment with ivermectin (CDTI). High infection levels have been reported in South-West Cameroon, despite ≥15 years of CDTI. The aim of this study was to assess factors associated with continued onchocerciasis transmission and skin disease. Methods A large-scale cross-sectional study was conducted in 2017 in 20 communities in a loiasis-risk area in South-West Cameroon. A mixed-methods approach was used. Associations between infection levels, skin disease and adherence to CDTI were assessed using mixed regression modelling. Different community members’ perception and acceptability of the CDTI strategy was explored using semi-structured interviews. Results Onchocerciasis prevalence was 44.4% among 9456 participants. 17.5% of adults were systematic non-adherers and 5.9% participated in ≥75% of CDTI rounds. Skin disease affected 1/10 participants, including children. Increasing self-reported adherence to CDTI was associated with lower infection levels in participants aged ≥15 years but not in children. Adherence to CDTI was positively influenced by perceived health benefits, and negatively influenced by fear of adverse events linked with economic loss. Concern of lethal adverse events was a common reason for systematic non-adherence. Conclusion CDTI alone is unlikely to achieve elimination in those high transmission areas where low participation is commonly associated with the fear of adverse events, despite the current quasi absence of high-risk levels of loiasis. Such persisting historical memories and fear of ivermectin might impact adherence to CDTI also in areas with historical presence but current absence of loiasis. Because such issues are unlikely to be tackled by CDTI adaptive measures, alternative strategies are needed for onchocerciasis elimination where negative perception of ivermectin is an entrenched barrier to community participation in programmes.
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Affiliation(s)
- Armelle Forrer
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, Merseyside, UK
| | - Samuel Wanji
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Elisabeth Dibando Obie
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Theobald Mue Nji
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Department of Sociology and Anthropology, University of Buea, Buea, Cameroon
| | - Louise Hamill
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, Merseyside, UK
| | - Kim Ozano
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, Liverpool, UK
| | - Helen Piotrowski
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, Liverpool, UK
| | - Laura Dean
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, Liverpool, UK
| | - Abdel J Njouendou
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Relindis Ekanya
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Winston Patrick Chounna Ndongmo
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Ebua Gallus Fung
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Department of Sociology and Anthropology, University of Buea, Buea, Cameroon
| | - Dum-Buo Nnamdi
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Department of Sociology and Anthropology, University of Buea, Buea, Cameroon
| | - Raphael A Abong
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Amuam Andrew Beng
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Mathias Esum Eyong
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Bertrand L Ndzeshang
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Desmond Akumtoh Nkimbeng
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Samuel Teghen
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Anicetus Suireng
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Ernerstine Ebot Ashu
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Emmanuel Kah
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Michele M Murdoch
- Watford General Hospital, West Herts Hospitals NHS Trust, Watford, UK
| | - Rachael Thomson
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, Merseyside, UK
| | - Sally Theobald
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, Liverpool, UK
| | - Peter Enyong
- Department of Disease Control, Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon.,Parasites and Vector Biology research unit (PAVBRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Joseph D Turner
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, Merseyside, UK
| | - Mark J Taylor
- Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, Merseyside, UK
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12
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Vinkeles Melchers NVS, Stolk WA, Murdoch ME, Pedrique B, Kloek M, Bakker R, de Vlas SJ, Coffeng LE. How does onchocerciasis-related skin and eye disease in Africa depend on cumulative exposure to infection and mass treatment? PLoS Negl Trop Dis 2021; 15:e0009489. [PMID: 34115752 PMCID: PMC8221783 DOI: 10.1371/journal.pntd.0009489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 06/23/2021] [Accepted: 05/19/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Onchocerciasis (river-blindness) in Africa is targeted for elimination through mass drug administration (MDA) with ivermectin. Onchocerciasis may cause various types of skin and eye disease. Predicting the impact of MDA on onchocercal morbidity is useful for future policy development. Here, we introduce a new disease module within the established ONCHOSIM model to predict trends over time in prevalence of onchocercal morbidity. METHODS We developed novel generic model concepts for development of symptoms due to cumulative exposure to dead microfilariae, accommodating both reversible (acute) and irreversible (chronic) symptoms. The model was calibrated to reproduce pre-control age patterns and associations between prevalences of infection, eye disease, and various types of skin disease as observed in a large set of population-based studies. We then used the new disease module to predict the impact of MDA on morbidity prevalence over a 30-year time frame for various scenarios. RESULTS ONCHOSIM reproduced observed age-patterns in disease and community-level associations between infection and disease reasonably well. For highly endemic settings with 30 years of annual MDA at 60% coverage, the model predicted a 70% to 89% reduction in prevalence of chronic morbidity. This relative decline was similar with higher MDA coverage and only somewhat higher for settings with lower pre-control endemicity. The decline in prevalence was lowest for mild depigmentation and visual impairment. The prevalence of acute clinical manifestations (severe itch, reactive skin disease) declined by 95% to 100% after 30 years of annual MDA, regardless of pre-control endemicity. CONCLUSION We present generic model concepts for predicting trends in acute and chronic symptoms due to history of exposure to parasitic worm infections, and apply this to onchocerciasis. Our predictions suggest that onchocercal morbidity, in particular chronic manifestations, will remain a public health concern in many epidemiological settings in Africa, even after 30 years of MDA.
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Affiliation(s)
| | - Wilma A. Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Michele E. Murdoch
- Department of Dermatology, West Herts Hospitals NHS Trust, Watford General Hospital, Watford, Hertfordshire, United Kingdom
| | - Belén Pedrique
- Drugs for Neglected Diseases initiative (DNDi), Geneva, Switzerland
| | - Marielle Kloek
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Roel Bakker
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sake J. de Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Luc E. Coffeng
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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13
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Cheke RA, Little KE, Young S, Walker M, Basáñez MG. Taking the strain out of onchocerciasis? A reanalysis of blindness and transmission data does not support the existence of a savannah blinding strain of onchocerciasis in West Africa. ADVANCES IN PARASITOLOGY 2021; 112:1-50. [PMID: 34024357 DOI: 10.1016/bs.apar.2021.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Onchocerciasis (also known as 'river blindness'), is a neglected tropical disease (NTD) caused by the (Simulium-transmitted) filarial nematode Onchocerca volvulus. The occurrence of 'blinding' (savannah) and non-blinding (forest) parasite strains and the existence of corresponding, locally adapted Onchocerca-Simulium complexes were postulated to explain greater blindness prevalence in savannah than in forest foci. As a result, the World Health Organization (WHO) Onchocerciasis Control Programme in West Africa (OCP) focused anti-vectorial and anti-parasitic interventions in savannah endemic areas. In this paper, village-level data on blindness prevalence, microfilarial prevalence, and transmission intensity (measured by the annual transmission potential, the number of infective, L3, larvae per person per year) were extracted from 16 West-Central Africa-based publications, and analysed according to habitat (forest, forest-savannah mosaic, savannah) to test the dichotomous strain hypothesis in relation to blindness. When adjusting for sample size, there were no statistically significant differences in blindness prevalence between the habitats (one-way ANOVA, P=0.68, mean prevalence for forest=1.76±0.37 (SE); mosaic=1.49±0.38; savannah=1.89±0.26). The well-known relationship between blindness prevalence and annual transmission potential for savannah habitats was confirmed and shown to hold for (but not to be statistically different from) forest foci (excluding data from southern Côte d'Ivoire, in which blindness prevalence was significantly lower than in other West African forest communities, but which had been the focus of studies leading to the strain-blindness hypothesis that was accepted by OCP planners). We conclude that the evidence for a savannah blinding onchocerciasis strain in simple contrast with a non-blinding forest strain is equivocal. A re-appraisal of the strain hypothesis to explain patterns of ocular disease is needed to improve understanding of onchocerciasis epidemiology and disease burden estimates in the light of the WHO 2030 goals for onchocerciasis.
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Affiliation(s)
- Robert A Cheke
- Natural Resources Institute, Department of Agriculture, Health & Environment, University of Greenwich at Medway, Kent, United Kingdom; London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom
| | | | - Stephen Young
- Natural Resources Institute, Department of Agriculture, Health & Environment, University of Greenwich at Medway, Kent, United Kingdom
| | - Martin Walker
- London Centre for Neglected Tropical Disease Research, Department of Pathobiology and Populations Sciences, Royal Veterinary College, Hatfield, United Kingdom
| | - Maria-Gloria Basáñez
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom; MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.
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14
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Churko C, Yihune M, Teshome A, Chisha Y, Getachew B, Sleshi M, Asfaw MA, Shibiru T, Ayele NN, Seife F, Zerdo Z, Bekele Kassahun A. Ivermectin Treatment Coverage Validation in Two Onchocerciasis Endemic Districts in Ethiopia: A Community-Based Cross-Sectional Study, 2019. J Multidiscip Healthc 2021; 14:137-144. [PMID: 33500622 PMCID: PMC7822083 DOI: 10.2147/jmdh.s288239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/17/2020] [Indexed: 01/15/2023] Open
Abstract
Background Onchocerciasis is the second leading cause of blindness globally next to trachoma, thus eliminating the infection is an important health priority. It is estimated that 15.7 million people are at risk of infection in different parts of Ethiopia. Mass drug administration with ivermectin at community and school level is the basis for control and elimination of onchocerciasis. This study was aimed at validating onchocerciasis treatment coverage in the selected districts of Ethiopia. Methods A community-based cross-sectional study was employed in Itang special and Wombera districts of Ethiopia, from April 1 to 30, 2019 G.C. We used a coverage validation survey builder tool to compute sample size. Individuals aged five years old and above were eligible population. Data were entered into Microsoft Excel and exported to STATA 14 for cleaning and analyses. A chi-square test was used to note statistical association of the outcome variables with independent variables. Main Findings A total of 3765 individuals were interviewed. Of these, 3244 were offered onchocerciasis treatment. The overall treatment coverage of onchocerciasis in the two selected districts of Ethiopia was 85.9% of the eligible population (3235/3765) (95% CI, 84.8%, 87%). There was significant difference between the two districts in terms of ivermectin offering (X2=70.467, P<0.001). School attendance was also significantly associated with treatment offering and swallowing status (X2=77.29, P<0.001; and X2=30.581, P<0.001). The main reported reasons for not being offered ivermectin were “being absent” (40.86%) and “not knowing about the mass drug administration” (MDA) (25.29%). Conclusion In conclusion, the treatment coverage of onchocerciasis in this survey was higher than minimum national desired therapeutic coverage. Treatment coverage in Wombera was higher than Itang special district. In addition, children who attended school had a higher chance of swallowing the drug.
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Affiliation(s)
- Chuchu Churko
- Collaborative Research and Training Center for Neglected Tropical Diseases, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Manaye Yihune
- Department of Public Health, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Abinet Teshome
- Department of Biomedical Sciences, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Yilma Chisha
- Department of Public Health, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | | | - Markos Sleshi
- Ethiopia Public Health Institute, Addis Ababa, Ethiopia
| | - Mekuria Asnakew Asfaw
- Collaborative Research and Training Center for Neglected Tropical Diseases, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Tamiru Shibiru
- School of Medicine, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | | | - Fikre Seife
- Neglected Tropical Diseases, Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Zerihun Zerdo
- Collaborative Research and Training Center for Neglected Tropical Diseases, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Alemayehu Bekele Kassahun
- Collaborative Research and Training Center for Neglected Tropical Diseases, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
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15
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Fuller LC, Asiedu KB, Hay RJ. Integration of Management Strategies for Skin-Related Neglected Tropical Diseases. Dermatol Clin 2020; 39:147-152. [PMID: 33228857 DOI: 10.1016/j.det.2020.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The concept of skin neglected tropical diseases has been widely adopted into the policy and strategy of various organizations, governments, nongovernmental organizations, and health agencies. By pooling information and resources across different diseases, whose primary manifestations affect the skin, it is possible to deliver integrated surveillance and control programs and promote advocacy and reduction of disability and stigma. A further key part of the skin neglected tropical diseases program is the development and validation of training methods for front-line health workers. Networks that allow those involved in this work to share and compare expertise are being developed through various organizations.
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Affiliation(s)
- Lucinda Claire Fuller
- Chelsea and Westminster NHS Foundation Trust, London SW10 9NH, UK; The International Foundation for Dermatology, London W1P 5HQ, UK.
| | - Kingsley B Asiedu
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva 1202, Switzerland
| | - Roderick J Hay
- The International Foundation for Dermatology, London W1P 5HQ, UK; The St John's Institute of Dermatology, King's College London, London SE1 9RT. UK
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16
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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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17
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Pasha MM, Patil CC, Tanuja M, Mitra D. A Rare Case of Cutaneous Onchocerciasis in North-East India, Review of Literature. Indian Dermatol Online J 2020; 11:600-603. [PMID: 32832451 PMCID: PMC7413433 DOI: 10.4103/idoj.idoj_555_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/29/2020] [Accepted: 04/20/2020] [Indexed: 11/24/2022] Open
Abstract
Onchocerca volvulus is a spirurid nematode that mainly affects the rural poor of Sub-Saharan Africa, Yemen, and parts of Central and South America. River blindness caused by Onchocerca volvulus is considered to be the second most common infectious cause of blindness worldwide. We report a rare case of cutaneous Onchocerciasis from a non endemic area of North-East India. We could extract live adult worms from the subcutaneous lesions and also micro filariae from the skin nips. Onchocerca was confirmed based on its morphology. The patient has been subjected to therapy with ivermectin and doxycycline and is currently on regular follow up.
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Affiliation(s)
- M M Pasha
- Department of Medicine, 5 Air Force Hospital, Rowarriah, Jorhat, Assam, India
| | - Chetan C Patil
- Department of Dermatology, 5 Air Force Hospital, Rowarriah, Jorhat, Assam, India
| | - M Tanuja
- Department of Pathology, 5 Air Force Hospital, Rowarriah, Jorhat, Assam, India
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18
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Murdoch ME. Mapping the burden of onchocercal skin disease. Br J Dermatol 2020; 184:199-207. [PMID: 32302410 DOI: 10.1111/bjd.19143] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2020] [Indexed: 02/06/2023]
Abstract
Onchocerciasis is a neglected tropical disease caused by a nematode parasite, Onchocerca volvulus, and transmitted by bites of Simulium blackflies which breed near fast-flowing rivers. In humans, thousands of microfilariae (immature worms) migrate to the skin and eyes where they cause pathology. Historically, much research was devoted to the serious effect of blindness, from which the disease earns its alternative name of 'river blindness'. Mapping the burden of onchocercal skin disease (OSD) was expedited by the development of a clinical classification and grading system that facilitated comparison of data from different countries. After successful field testing in Nigeria, the classification scheme was used in a multicountry study in seven endemic sites, to estimate the true burden of OSD across Africa. High levels of OSD were found, affecting 28% of the population. A new control programme, the African Programme for Onchocerciasis Control (APOC) was launched in 20 countries using annual doses of ivermectin, donated by Merck & Co., Inc. The multicountry study also found a close correlation between the levels of itching and OSD with the level of endemicity, as determined by the prevalence of onchocercal nodules. This enabled APOC to use Rapid Epidemiological Mapping of Onchocerciasis, which entailed identifying likely vector breeding sites near rivers, then sampling 50 adult males in nearby villages to determine the prevalence of nodules and delineate which villages required treatment. Onchocerciasis is now targeted for elimination in Africa, and the challenge is to complete Onchocerciasis Elimination Mapping of hypoendemic areas using serology.
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Affiliation(s)
- M E Murdoch
- Department of Dermatology, West Herts Hospitals NHS Trust, Watford General Hospital, Watford, WD18 0HB, UK
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19
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Molkara S, Sabourirad S, Molooghi K. Infectious differential diagnosis of chronic generalized pruritus without primary cutaneous lesions: a review of the literature. Int J Dermatol 2020; 59:30-36. [PMID: 31364165 DOI: 10.1111/ijd.14587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 06/03/2019] [Accepted: 06/19/2019] [Indexed: 01/24/2023]
Abstract
Pruritus is one of the most common complaints among patients referred to a dermatology clinic. "Chronic generalized pruritus" is described as the sensation of itching on the entire body surface, which lasts at least 6 or more weeks. This symptom can be a disabling phenomenon for patients and may sometimes interfere with daily activities such as sleep. If specific dermatological findings are observed, the physician easily comes to a diagnosis and treats the condition, whereas, when primary lesions are not detected, the diagnosis can become challenging, and some patients have to undergo extensive evaluations. The association between some systemic disorders and chronic generalized pruritus is widely known and confirmed. Many infections have been associated with pruritus, but few are considered to cause chronic generalized pruritus without any characteristic skin lesions. We aimed to gather all the available data on infectious causes of chronic generalized pruritus with no diagnostic cutaneous lesions to assist fellow physicians in the process of evaluation of these challenging cases.
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Affiliation(s)
- Sara Molkara
- Cutaneous Leishmaniasis Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Sara Sabourirad
- Cutaneous Leishmaniasis Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Kasra Molooghi
- Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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20
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Wanji S, Nji TM, Hamill L, Dean L, Ozano K, Njouendou AJ, Abong RA, Obie ED, Amuam A, Ekanya R, Ndongmo WPC, Ndzeshang BL, Fung EG, Nnamdi DB, Nkimbeng DA, Teghen S, Kah E, Piotrowski H, Forrer A, Khan JAM, Woode ME, Niessen L, Watson V, Njoumemi Z, Murdoch ME, Thomson R, Theobald S, Enyong P, Turner JD, Taylor MJ. Implementation of test-and-treat with doxycycline and temephos ground larviciding as alternative strategies for accelerating onchocerciasis elimination in an area of loiasis co-endemicity: the COUNTDOWN consortium multi-disciplinary study protocol. Parasit Vectors 2019; 12:574. [PMID: 31801631 PMCID: PMC6894124 DOI: 10.1186/s13071-019-3826-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 11/25/2019] [Indexed: 12/15/2022] Open
Abstract
Background Onchocerciasis is a priority neglected tropical disease targeted for elimination by 2025. The standard strategy to combat onchocerciasis is annual Community-Directed Treatment with ivermectin (CDTi). Yet, high prevalence rates and transmission persist following > 12 rounds in South-West Cameroon. Challenges include programme coverage, adherence to, and acceptability of ivermectin in an area of Loa loa co-endemicity. Loiasis patients harbouring heavy infections are at risk of potentially fatal serious adverse events following CDTi. Alternative strategies are therefore needed to achieve onchocerciasis elimination where CDTi effectiveness is suboptimal. Methods/design We designed an implementation study to evaluate integrating World Health Organisation-endorsed alternative strategies for the elimination of onchocerciasis, namely test-and-treat with the macrofilaricide, doxycycline (TTd), and ground larviciding for suppression of blackfly vectors with the organophosphate temephos. A community-based controlled before-after intervention study will be conducted among > 2000 participants in 20 intervention (Meme River Basin) and 10 control (Indian River Basin) communities. The primary outcome measure is O. volvulus prevalence at follow-up 18-months post-treatment. The study involves four inter-disciplinary components: parasitology, entomology, applied social sciences and health economics. Onchocerciasis skin infection will be diagnosed by skin biopsy and Loa loa infection will be diagnosed by parasitological examination of finger-prick blood samples. A simultaneous clinical skin disease assessment will be made. Eligible skin-snip-positive individuals will be offered directly-observed treatment for 5 weeks with 100 mg/day doxycycline. Transmission assessments of onchocerciasis in the communities will be collected post-human landing catch of the local biting blackfly vector prior to ground larviciding with temephos every week (0.3 l/m3) until biting rate falls below 5/person/day. Qualitative research, including in-depth interviews and focus-group discussions will be used to assess acceptability and feasibility of the implemented alternative strategies among intervention recipients and providers. Health economics will assess the cost-effectiveness of the implemented interventions. Conclusions Using a multidisciplinary approach, we aim to assess the effectiveness of TTd, alone or in combination with ground larviciding, following a single intervention round and scrutinise the acceptability and feasibility of implementing at scale in similar hotspots of onchocerciasis infection, to accelerate onchocerciasis elimination.
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Affiliation(s)
- Samuel Wanji
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon. .,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.
| | - Theobald Mue Nji
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, P.O. Box 63, Buea, Cameroon
| | | | - Laura Dean
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Kim Ozano
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Abdel J Njouendou
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Biomedical Sciences, Faculty of Health Sciences, University of Buea, P.O. Box 12, Buea, Cameroon
| | - Raphael A Abong
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Elisabeth Dibando Obie
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Andrew Amuam
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Relindis Ekanya
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Winston Patrick Chounna Ndongmo
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Bertrand L Ndzeshang
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Ebua Gallus Fung
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Dum-Buo Nnamdi
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Desmond Akumtoh Nkimbeng
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Samuel Teghen
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Emmanuel Kah
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Helen Piotrowski
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Armelle Forrer
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Jahangir A M Khan
- COUNTDOWN, Department of Clinical Sciences, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Maame E Woode
- Centre for Health Economics, Monash University, Victoria, Australia
| | - Louis Niessen
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK.,Department of International Health, Johns Hopkins School of Public Health, Baltimore, USA
| | - Victoria Watson
- COUNTDOWN, Department of Clinical Sciences, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Zakariaou Njoumemi
- Health Economics Unit, Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaounde I, P.O. Box 1364, Yaounde, Cameroon
| | - Michele E Murdoch
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK.,West Herts Hospitals NHS Trust, Watford General Hospital, Vicarage Road, Watford, UK
| | - Rachael Thomson
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Sally Theobald
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Peter Enyong
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Joseph D Turner
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK.
| | - Mark J Taylor
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
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Schwartz RA, Al-Qubati Y, Zieleniewski Ł, Shah R, Kapila R. Onchocerciasis (river blindness): larva-induced eczema (onchodermatitis) from an important oculocutaneous tropical disease spilling over into North America and Europe. Int J Dermatol 2019; 59:1065-1070. [PMID: 31513297 DOI: 10.1111/ijd.14614] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/05/2019] [Accepted: 08/09/2019] [Indexed: 11/28/2022]
Abstract
Onchocerciasis is a leading cause of blindness in the world. It may be seen in temperate climates of the United States and Europe in immigrants and travelers from endemic regions, often linked to poverty and war. One should be aware of an incubation period that can be up to 15 months. In its early stage and throughout its course, onchocerciasis has noteworthy skin findings, facilitating diagnosis, as onchodermatitis resembles common eczema with variable degrees of papular, lichenoid, atrophic, and pigmentary alterations, features not suggestive if one is unaware of an individual's immigration and travel history. The same concept applies for the encysted worms (onchocercomas), as they tend to appear as common skin cysts and benign neoplasms. New methods can be employed to increase diagnostic sensitivity and specificity. Ivermectin is the gold standard of therapy, the use of which has almost miraculously eliminated this disease from large areas of the earth. However, its effect remains isolated to microfilariae and can be devastating in those coinfected with Loa loa. Recently, the symbiotic relationship between adult worms and Wolbachia bacteria has been discovered and, with it, the possibility of adding doxycycline as a treatment option. We also discuss coinfection with HIV and other diseases.
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Affiliation(s)
- Robert A Schwartz
- Professor & Head, Dermatology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | | | - Łukasz Zieleniewski
- Nicolaus Copernicus University Ludwig Rydygier Medical College, Bydgoszcz, Poland
| | - Radhika Shah
- Professor & Head, Dermatology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Rajendra Kapila
- Professor & Head, Dermatology, Rutgers New Jersey Medical School, Newark, NJ, USA
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22
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Siewe JFN, Ngarka L, Tatah G, Mengnjo MK, Nfor LN, Chokote ES, Boullé C, Nkouonlack C, Dema F, Nkoro GA, Njamnshi WY, Tabah EN, Zoung-Kanyi Bissek AC, Colebunders R, Njamnshi AK. Clinical presentations of onchocerciasis-associated epilepsy (OAE) in Cameroon. Epilepsy Behav 2019; 90:70-78. [PMID: 30513438 DOI: 10.1016/j.yebeh.2018.11.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/16/2018] [Accepted: 11/12/2018] [Indexed: 10/27/2022]
Abstract
BACKGROUND A high prevalence of epilepsy has been observed in several onchocerciasis-endemic countries, including Cameroon. However, little is known on the clinical presentations of the affected persons with epilepsy (PWE). A community-based study was conducted with the aim of describing the spectrum of seizures in selected onchocerciasis-endemic villages in Cameroon and documenting relevant medical history in patients with onchocerciasis-associated epilepsy (OAE). METHODS We carried out door-to-door surveys in 5 onchocerciasis-endemic villages in Cameroon and recruited all consenting PWE. Epilepsy was diagnosed using a 2-step approach consisting of the administration of a standardized 5-item questionnaire followed by confirmation of the suspected cases by a neurologist. Onchocerciasis-associated epilepsy was defined as ≥2 seizures without an obvious cause, starting between the ages of 3-18 years in previously healthy persons having resided for at least 3 years in an onchocerciasis-endemic area. Ivermectin use by PWE was verified. Seizure history, relevant past medical, and family history, as well as neurological findings, were noted. RESULTS In all, 156 PWE were recruited in the 5 villages. The modal age group for epilepsy onset was 10-14 years. The diagnostic criteria for OAE were met by 93.2% of the PWE. Participants had one or more of the following seizure types: generalized tonic-clonic seizures (89.1%), absences (38.5%), nodding (21.8%), focal nonmotor (7.7%), and focal motor seizures (1.9%). One case (0.6%) with the "Nakalanga syndrome" was identified. More than half (56.4%) of PWE had at least one seizure per month. In one village, 56.2% of PWE had onchocercal skin lesions. CONCLUSION People with epilepsy in onchocerciasis-endemic villages in Cameroon present with a wide clinical spectrum including nodding seizures and Nakalanga features. A great majority of participants met the diagnostic criteria for OAE, suggesting that better onchocerciasis control could prevent new cases. Epilepsy management algorithms in these areas must be adjusted to reflect the varied seizure types.
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Affiliation(s)
| | - Leonard Ngarka
- Neurology Department, Yaoundé Central Hospital, Cameroon; Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon
| | - Godwin Tatah
- Neurology Department, Yaoundé Central Hospital, Cameroon; Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon; Neurology Department, CH Saint Nazaire, France
| | - Michel K Mengnjo
- Neurology Department, Yaoundé Central Hospital, Cameroon; Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon
| | - Leonard N Nfor
- Neurology Department, Yaoundé Central Hospital, Cameroon; Neurology Department, CHU Brugmann, Belgium
| | - Eric S Chokote
- Neurology Department, Yaoundé Central Hospital, Cameroon; Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon
| | - Charlotte Boullé
- Institut de Recherche pour le Développement, UMI 233-Inserm U1175-Montpellier University, France
| | | | | | - Grace A Nkoro
- Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon
| | - Wepnyu Y Njamnshi
- Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon; Faculty of Science and Medicine, University of Fribourg, Switzerland
| | | | | | | | - Alfred K Njamnshi
- Neurology Department, Yaoundé Central Hospital, Cameroon; Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Cameroon; Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon.
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23
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Hotterbeekx A, Namale Ssonko V, Oyet W, Lakwo T, Idro R. Neurological manifestations in Onchocerca volvulus infection: A review. Brain Res Bull 2018; 145:39-44. [PMID: 30458251 PMCID: PMC6382410 DOI: 10.1016/j.brainresbull.2018.08.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 08/22/2018] [Accepted: 08/25/2018] [Indexed: 11/17/2022]
Abstract
Human onchocerciasis, caused by infection by the filarial nematode Onchocerca volvulus, is a major neglected public health problem that affects millions of people in the endemic regions of sub-Saharan Africa and Latin America. Onchocerciasis is known to be associated with skin and eye disease and more recently, neurological features have been recognized as a major manifestation. Especially the latter poses a severe burden on affected individuals and their families. Although definite studies are awaited, preliminary evidence suggests that neurological disease may include the nodding syndrome, Nakalanga syndrome and epilepsy but to date, the exact pathophysiological mechanisms remain unclear. Currently, the only way to prevent Onchocera volvulus associated disease is through interventions that target the elimination of onchocerciasis through community distribution of ivermectin and larviciding the breeding sites of the Similium or blackfly vector in rivers. In this review, we discuss the epidemiology, potential pathological mechanisms as well as prevention and treatment strategies of onchocerciasis, focusing on the neurological disease.
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Affiliation(s)
- An Hotterbeekx
- University of Antwerp, Global Health Institute, Antwerp, Belgium
| | | | | | - Thomson Lakwo
- Ministry of Health, Division of Vector Control, Kampala, Uganda
| | - Richard Idro
- Makerere University College of Health Sciences, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda; University of Oxford, Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford, UK.
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24
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Saleem MD, Oussedik E, Schoch JJ, Berger AC, Picardo M. Acquired disorders with depigmentation: A systematic approach to vitiliginoid conditions. J Am Acad Dermatol 2018; 80:1215-1231.e6. [PMID: 30236516 DOI: 10.1016/j.jaad.2018.03.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 03/01/2018] [Accepted: 03/21/2018] [Indexed: 01/14/2023]
Abstract
Acquired disorders with depigmentation are commonly encountered by dermatologists and present with a wide differential diagnosis. Vitiligo, the most common disorder of acquired depigmentation, is characterized by well-defined depigmented macules and patches. Other conditions, such as chemical leukoderma, can present with similar findings, and are often easily mistaken for vitiligo. Key clinical features can help differentiate between acquired disorders of depigmentation. The first article in this continuing medical education series focuses on conditions with a vitiligo-like phenotype. Early recognition and adequate treatment of these conditions is critical in providing appropriate prognostication and treatment.
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Affiliation(s)
- Mohammed D Saleem
- Department of Internal Medicine, University of Florida College of Medicine and University of Florida Health, Gainesville, Florida.
| | | | - Jennifer J Schoch
- Department of Dermatology and Pediatrics, University of Florida, Gainesville, Florida
| | - Adam C Berger
- Department of Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Mauro Picardo
- Department of Dermatology and Pediatric Dermatology, Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
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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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Osue HO. Field-Based Evidence of Single and Few Doses of Annual Ivermectin Treatment Efficacy in Eliminating Skin Microfilaria Load after a Decade of Intervention. Ethiop J Health Sci 2018; 27:129-138. [PMID: 28579708 PMCID: PMC5440827 DOI: 10.4314/ejhs.v27i2.5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background Impact assessment of community-based ivermectin treatment control of onchocerciasis is required to determine its effectiveness. This study was conducted to evaluate geographic coverage and demographic ivermectin treatment compliance. Methods The number of village dosage were obtained from the community based distributors. Bioclinical data of participants comprising gender, age, number of treatment received from inception and dosage were obtained. Each participant was subjected to physical examination for palpable nodule and other skin clinical signs and symptoms of onchocerciasis. Visual acuity test was done using the Snellen illiterate E-chart. Eye examination was performed using touch loop and handheld ophthalmoscope. Skin snips from both iliac crests were incubated overnight at 28–32°C and emerged micrifilaria enumerated under an inverted microscope. The changes in epidemiological indices at post-decade of mass drug administration were compared with baseline data. Results Village annual ivermectin treatment doses averaged 62%, ranging between 10–100%. Individual treatment compliance rate was generally low with an average of 4 treatments and a range between 0–10. Despite variations in treatment compliance, there were significant improvements in some onchocercal morbidities. These include reduced number and severity of itching, visual impairment, papular onchodermatitis, onchocercomata (palpable nodules) and leopard skin. Ivermectin treatment halted development of new blind cases, except the case of a man who had optic nerve disease and became blind 2 years after ivermectin treatment had commenced. There was a significant overall reduction in parasite burden with very low mean skin microfilaria load of 1.7mf per skin snip and 3.7% skin mf prevalence, compared to baseline data of 17.7mf and 37.9% respectively. The palpable nodule was also drastically reduced from 14.5% to 6.4%. Outcome of this study has practically demonstrated that even a single dose ivermectin treatment is capable of clearing skin mf load on a long-term basis. This assertion is exemplified by the result obtained from Bomjock village that had taken treatment only at inception, and the prevalence rate was reduced from 70% to about 9.0% at post-decade of intervention. Conclusion It can be inferred that high demographic coverage with annual treatment doses, it is feasible to attain a shorter time (within a decade) contrary to the anticipated longer-term projection.
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Affiliation(s)
- Hudu O Osue
- Nigerian Institute for Trypanosomiasis (and Onchocerciasis) Research (NITR), Kaduna, Nigeria
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Abstract
A variety of arthropods, protozoa, and helminths infect the skin and subcutaneous tissues and may be identified by anatomic pathologists in standard cytology and histology preparations. The specific organisms seen vary greatly with the patient's exposure history, including travel to or residence in endemic countries. Arthropods are the most commonly encountered parasites in the skin and subcutaneous tissues and include Sarcoptes scabei, Demodex species, Tunga penetrans, and myiasis-causing fly larvae. Protozoal parasites such as Leishmania may also be common in some settings. Helminths are less often seen, and include round worms (eg, Dirofilaria spp.), tapeworms (eg, Taenia solium, Spirometra spp.), and flukes (eg, Schistosoma spp.). This review covers the epidemiologic and histopathologic features of common parasitic infections of the skin and subcutaneous tissues.
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Al-Kubati AS, Mackenzie CD, Boakye D, Al-Qubati Y, Al-Samie AR, Awad IE, Thylefors B, Hopkins A. Onchocerciasis in Yemen: moving forward towards an elimination program. Int Health 2018; 10:i89-i96. [DOI: 10.1093/inthealth/ihx055] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Indexed: 11/13/2022] Open
Affiliation(s)
- Abdul-Samid Al-Kubati
- Skin and Venereal Diseases Hospital, National Leprosy Elimination Program, Taiz, Republic of Yemen
| | | | - Daniel Boakye
- Faculty of Medicine, Taiz University, Taiz, Republic of Yemen
| | | | | | | | - Bjorn Thylefors
- Mectizan Donation Program, Task Force for Global Health, Atlanta, GA, USA
| | - Adrian Hopkins
- Mectizan Donation Program, Task Force for Global Health, Atlanta, GA, USA
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Puente S, Ramirez-Olivencia G, Lago M, Subirats M, Perez-Blazquez E, Bru F, Garate T, Vicente B, Belhassen-Garcia M, Muro A. Dermatological manifestations in onchocerciasis: A retrospective study of 400 imported cases. Enferm Infecc Microbiol Clin 2017; 36:633-639. [PMID: 29275076 DOI: 10.1016/j.eimc.2017.11.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/16/2017] [Accepted: 11/17/2017] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Onchocerciasis is caused by Onchocerca volvulus and mainly leads to pruritus and skin and visual disorders, including blindness. Seventeen million people are infected in 38 countries; 31 of these are in sub-Saharan Africa, six in Latin America and one on the Arabian Peninsula. More than 99% of cases occur in sub-Saharan Africa where 120 million people are at risk of infection. Eye disorders have been well-documented; however, skin disorders have not been described accurately. The objective of our study was to describe the epidemiology, main skin manifestations and treatment of imported onchocerciasis. MATERIAL AND METHODS A retrospective study was thus conducted by analysing the main demographic, clinical and treatment data regarding a cohort of 400 patients attending a reference clinical unit over a 17-year period. RESULTS Most patients were female (55%) with mean age 37.5±16.7 years. All the migrants came from sub-Saharan countries. The most frequently occurring dermatological symptom was pruritus. Ivermectin had been used as first-line therapy and adverse reactions had been described in 11 patients (3.2%). CONCLUSIONS The results indicate the fact that there should be a clinical suspicion of onchocerciasis regarding immigrants from endemic areas having skin lesions compatible with the disease's profile or asymptomatic patients having eosinophilia or unexplained high IgE. Moreover, skin snips from the buttocks region were very fruitful and treatment with ivermectin was seen to be safe. This is the largest case series regarding imported onchocerciasis described up to the present time.
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Affiliation(s)
- Sabino Puente
- Unidad de Medicina Tropical, Servicio de Medicina Interna, Hospital La Paz-Carlos III, Madrid, Spain
| | - German Ramirez-Olivencia
- Unidad de Aislamiento de Alto Nivel, Sección de Enfermedades Infecciosas, Servicio de Medicina Interna, Hospital Central de la Defensa Gómez Ulla, Madrid, Spain
| | - Mar Lago
- Unidad de Medicina Tropical, Servicio de Medicina Interna, Hospital La Paz-Carlos III, Madrid, Spain
| | | | - Eugenio Perez-Blazquez
- Servicio de Oftalmología, Hospital Universitario 12 de Octubre, Universidad complutense de Madrid, Spain
| | | | - Teresa Garate
- Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Belén Vicente
- Laboratorio de Inmunología Parasitaria y Molecular, CIETUS, IBSAL, Facultad de Farmacia, Universidad de Salamanca, Salamanca, Spain
| | - Moncef Belhassen-Garcia
- Servicio de Medicina Interna, Sección de Enfermedades Infecciosas, CAUSA, IBSAL, CIETUS, Universidad de Salamanca, Salamanca, Spain
| | - Antonio Muro
- Laboratorio de Inmunología Parasitaria y Molecular, CIETUS, IBSAL, Facultad de Farmacia, Universidad de Salamanca, Salamanca, Spain.
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Norice-Tra CT, Ribeiro J, Bennuru S, Fay MP, Tyagi R, Mitreva M, Nutman TB. Insights Into Onchocerca volvulus Population Biology Through Multilocus Immunophenotyping. J Infect Dis 2017; 216:736-743. [PMID: 28934436 DOI: 10.1093/infdis/jix394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 08/03/2017] [Indexed: 11/13/2022] Open
Abstract
We have developed a serologically based immunophenotyping approach to study Onchocerca volvulus (Ov) population diversity. Using genomic sequence data and polymerase chain reaction-based genotyping, we identified nonsynonymous single-nucleotide polymorphisms (SNPs) in the genes of 16 major immunogenic Ov proteins: Ov-CHI-1/Ov-CHI-2, Ov16, Ov-FAR-1, Ov-CPI-1, Ov-B20, Ov-ASP-1, Ov-TMY-1, OvSOD1, OvGST1, Ov-CAL-1, M3/M4, Ov-RAL-1, Ov-RAL-2, Ov-ALT-1, Ov-FBA-1, and Ov-B8. We assessed the immunoreactivity of onchocerciasis patient sera (n = 152) from the Americas, West Africa, Central Africa, and East Africa against peptides derived from 10 of these proteins containing SNPs. Statistically significant variation in immunoreactivity among the regions was seen in SNP-containing peptides derived from 8 of 10 proteins tested: OVOC1192(1-15), OVOC9988(28-42), OVOC9225(320-334), OVOC7453(22-36), OVOC11517(14-28), OVOC3177(283-297), OVOC7911(594-608), and OVOC12628(174-188). Our data show that differences in immunoreactivity to variant antigenic peptides may be used to characterize Ov populations, thereby elucidating features of Ov population biology previously inaccessible because of the limited availability of parasite material.
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Affiliation(s)
| | | | | | - Michael P Fay
- Biostatistics Research Branch, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | | | - Makedonka Mitreva
- McDonnell Genome Institute.,Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
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Murdoch ME, Murdoch IE, Evans J, Yahaya H, Njepuome N, Cousens S, Jones BR, Abiose A. Pre-control relationship of onchocercal skin disease with onchocercal infection in Guinea Savanna, Northern Nigeria. PLoS Negl Trop Dis 2017; 11:e0005489. [PMID: 28355223 PMCID: PMC5386293 DOI: 10.1371/journal.pntd.0005489] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 04/10/2017] [Accepted: 03/13/2017] [Indexed: 01/22/2023] Open
Abstract
Background Onchocerca volvulus infection can result in blindness, itching and skin lesions. Previous research concentrated on blindness. Methods A clinical classification system of the cutaneous changes in onchocerciasis was used for the first time in this study within the context of an early ivermectin drug trial in the savanna region of Kaduna State, northern Nigeria. Skin examinations were performed in 6,790 individuals aged 5+ years in endemic communities and 1,343 individuals in nonendemic communities. Results / Discussion There was increased risk for all forms of onchocercal skin disease in endemic communities with the most common finding being the presence of nodules (1,438 individuals, 21.2%), followed by atrophy (367, 6.1% of those < 50 years), acute papular onchodermatitis, APOD (233, 3.4%), depigmentation (216, 3.2%) and chronic papular onchodermatitis, CPOD (155, 2.3%). A further 645 individuals (9.5%) complained of pruritus but had completely normal skin. APOD was more common in males whereas atrophy, hanging groin and nodules were more common in females. After controlling for age and sex, microfilarial positivity was a risk factor for CPOD, depigmentation, hanging groin and nodules (OR 1.54, p = 0.046; OR 2.29, p = 0.002; OR 2.18, p = 0.002 and OR 3.80, p <0.001 respectively). Comparable results were found using presence of nodules as the marker for infection. Microfilarial load showed similar, though weaker, results. A total of 2621(38.6%) endemic residents had itching with normal skin, or had one or more types of onchocercal skin disease including nodules, which may be considered as a composite index of the overall prevalence of onchocercal skin disease. Conclusion Significant levels of onchocercal skin disease were documented in this savanna area, which subsequently resulted in a reassessment of the true burden of skin disease in onchocerciasis. This paper represents the first detailed report of the association of onchocercal skin disease with markers for onchocercal infection. Onchocerciasis is a tropical parasitic infection caused by the nematode worm Onchocerca volvulus. The disease mainly occurs across tropical Africa and infection can result in blindness, debilitating itching and a variety of skin changes. Initial research concentrated mainly on the problem of blindness. A number of studies on onchocercal skin disease were performed but were difficult to interpret and compare because of the use of inconsistent terminology. Within the setting of one of the early trials of ivermectin in a savanna area of northern Nigeria, where there were known high rates of onchocercal blindness, we used a novel clinical classification of the skin changes in onchocerciasis. We identified significant levels of itching and various forms of onchocercal skin disease within these endemic communities. A positive skin-snip result proved to be a significant risk factor for the presence of chronic papular onchodermatitis (CPOD), depigmentation, hanging groin and onchocercal nodules. Comparable results were found when the presence of nodules was used as the marker for infection and similar, though weaker odds ratios were found with microfilarial load per se. The findings triggered a reassessment of the true burden of skin disease in onchocerciasis. It is the first detailed report of the association between onchocercal skin disease and markers of infection.
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Affiliation(s)
- Michele E. Murdoch
- St. John's Institute of Dermatology, London, United Kingdom
- Department of Dermatology, Watford General Hospital, West Herts Hospitals NHS Trust, Watford, Herts., United Kingdom
- * E-mail:
| | - Ian E. Murdoch
- Department of Ophthalmology, Ahmadu Bello University Hospital, Kaduna, Nigeria
- International Centre for Eye Health, Institute of Ophthalmology, London, United Kingdom
| | - Jennifer Evans
- Department of Ophthalmology, Ahmadu Bello University Hospital, Kaduna, Nigeria
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Haliru Yahaya
- Department of Medicine, Ahmadu Bello University Teaching Hospital, Kaduna, Nigeria
| | - Ngozi Njepuome
- Department of Medicine, Ahmadu Bello University Teaching Hospital, Kaduna, Nigeria
| | - Simon Cousens
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Barrie R. Jones
- Department of Ophthalmology, Ahmadu Bello University Hospital, Kaduna, Nigeria
- International Centre for Eye Health, Institute of Ophthalmology, London, United Kingdom
| | - Adenike Abiose
- Department of Ophthalmology, Ahmadu Bello University Hospital, Kaduna, Nigeria
- National Eye Centre, Kaduna, Nigeria
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Onchocerciasis in the Democratic Republic of Congo: Survey of knowledge, attitude and perception in Bandundu province. J Infect Public Health 2017; 10:600-607. [PMID: 28215917 DOI: 10.1016/j.jiph.2017.01.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 01/16/2017] [Accepted: 01/28/2017] [Indexed: 11/23/2022] Open
Abstract
A community-directed treatment with ivermectin (CDTI) for fighting onchocerciasis was started in 2003 in the hyperendemic province of Bandundu, Democratic Republic of Congo (DRC); such initiative was supported by the African Programme for Onchocerciasis Control (APOC). As the APOC stopped at the end of 2015, there was an urgent need to assess the sustainability of an ivermectin treatment. A cross-sectional survey of knowledge, attitude and perception was conducted to determine the awareness level of local population regarding the disease. A multi-stage random sampling technique allowed the selection of 450 heads of households. Most respondents (96.9%) knew about onchocerciasis as a disease. The black-fly was viewed as the causing agent of onchocerciasis by 49.9% of respondents. The most commonly cited clinical manifestations were nodules (34.4%) and pruritus (31.1%), while blindness was the most frequently reported complication (90.7%). Approximately 55.1% of respondents had a good knowledge of onchocerciasis and CDTI. Overall, only 37% of participants had a favourable attitude and 46% a positive perception. Good knowledge was associated with school attendance (adjusted OR=1.9, 95%CI: 1.3-2.8, p=0.001), while education and continuation of treatment were related with good attitude (adjusted OR=9.7, 95%CI:4.8-19.5 and adjusted OR=19.8, 95%CI: 9.7-40.6, respectively, both with p<0.001). Good perception was associated with being at least 46 years old, non-Catholic and continuing the treatment (adjusted OR=3.2, 95%CI:1.2-9.1; adjusted OR=29.6, 95%CI:14.1-62.2 and adjusted OR=5.1, 95%CI:1.6-16.0 respectively, all with p<0.001). A good level of knowledge, attitude and perception is needed for a massive adherence of population to onchocerciasis control programmes. In the area of study (Moanza, DRC), good attitude and perception motivated the continuation of treatment in the population. In the future, different plans should focus on educational strategies to maintain a massive adherence and reduce onchocerciasis prevalence.
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Hagan M. Onchocercal dermatitis: clinical impact. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2016. [DOI: 10.1080/00034983.1998.11813371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Ogbuagu KF, Eneanya CI. A multi-centre study of the effect of Mectizan treatment on onchocercal skin disease: clinical findings. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2016. [DOI: 10.1080/00034983.1998.11813378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Moya L, Herrador Z, Ta-Tang TH, Rubio JM, Perteguer MJ, Hernandez-González A, García B, Nguema R, Nguema J, Ncogo P, Garate T, Benito A, Sima A, Aparicio P. Evidence for Suppression of Onchocerciasis Transmission in Bioko Island, Equatorial Guinea. PLoS Negl Trop Dis 2016; 10:e0004829. [PMID: 27448085 PMCID: PMC4957785 DOI: 10.1371/journal.pntd.0004829] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 06/16/2016] [Indexed: 11/30/2022] Open
Abstract
Onchocerciasis or "river blindness" is a chronic parasitic neglected tropical disease which is endemic both in mainland and insular Equatorial Guinea. We aim to estimate the current epidemiological situation of onchocerciasis in Bioko Island after vector elimination in 2005 and more than sixteen years of Community Directed Treatment with Ivermectin (CDTI) by using molecular and serological approaches for onchocerciasis diagnosis. A community-based cross-sectional study was carried out in Bioko Island from mid-January to mid-February 2014. A total of 544 study participants were recruited. A complete dermatological examination was performed and three skin snips were performed in every participant for parasitological and molecular assessments. Blood spots were also taken for determination of Ov16 IgG4 antibodies trough an “in-house” ELISA assay. Overall, we found 15 out of 522 individuals suffering any onchocerciasis specific cutaneous lesions and 16 out of 528 (3.0%) with onchocercal nodules in the skin. Nodules were significantly associated with age, being more common in subjects older than 10 years than in younger people (3.9% vs. 0%, p = 0.029). Regarding the onchocerciasis laboratory assessment, no positive parasitological test for microfilaria detection was found in the skin snips. The calculated seroprevalence through IgG4 serology was 7.9%. No children less than 10 years old were found to be positive for this test. Only one case was positive for Onchocerca volvulus (O. volvulus) after skin PCR. The present study points out that the on-going mass ivermectin treatment has been effective in reducing the prevalence of onchocerciasis and corroborates the interruption of transmission in Bioko Island. To our knowledge, this is the first time that accurate information through molecular and serological techniques is generated to estimate the onchocerciasis prevalence in this zone. Sustained support from the national program and appropriate communication and health education strategies to reinforce participation in CDTI activities are essential to ensure progress towards onchocerciasis elimination in the country. Onchocerciasis or “river blindness” is a chronic parasitic disease which is mainly found in Sub-Saharan Africa. Onchocerciasis is endemic in both mainland and insular Equatorial Guinea. Huge achievements have been made on onchocerciasis control in Bioko Island in the last years, and the country is moving fast towards elimination. In the new elimination context, monitoring and evaluation activities with more sensitive diagnostic tools become especially necessary in order to confirm that transmission has been interrupted. Previous data on the epidemiological situation of onchocerciasis in Bioko Island are mainly based on microfilaria (MF) skin snip assessments. We aim to create evidence towards the fact that onchocerciasis transmission might have been achieved in Bioko Island after more than sixteen years of onchocerciasis control activities by using molecular and serological technics for onchocerciasis diagnosis.
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Affiliation(s)
- Laura Moya
- Jimenez Diaz Foundation, Madrid, Spain
- National Center for Tropical Medicine, Institute of Health Carlos III, Madrid, Spain
- * E-mail:
| | - Zaida Herrador
- National Center for Tropical Medicine, Institute of Health Carlos III, Madrid, Spain
- Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
| | - Thuy Huong Ta-Tang
- Malaria & Other Emerging Parasitic Diseases Laboratory, National Microbiology Center, Institute of Health Carlos III, Madrid, Spain
| | - Jose Miguel Rubio
- Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
- Malaria & Other Emerging Parasitic Diseases Laboratory, National Microbiology Center, Institute of Health Carlos III, Madrid, Spain
| | - Maria Jesús Perteguer
- Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
- Malaria & Other Emerging Parasitic Diseases Laboratory, National Microbiology Center, Institute of Health Carlos III, Madrid, Spain
| | - Ana Hernandez-González
- Malaria & Other Emerging Parasitic Diseases Laboratory, National Microbiology Center, Institute of Health Carlos III, Madrid, Spain
| | - Belén García
- National Center for Tropical Medicine, Institute of Health Carlos III, Madrid, Spain
| | - Rufino Nguema
- National Program for Onchocerciasis and other Filariasis Control, Ministry of Health, Malabo, Equatorial Guinea
| | - Justino Nguema
- National Program for Onchocerciasis and other Filariasis Control, Ministry of Health, Malabo, Equatorial Guinea
| | - Policarpo Ncogo
- National Center for Tropical Medicine, Institute of Health Carlos III, Madrid, Spain
| | - Teresa Garate
- Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
- Malaria & Other Emerging Parasitic Diseases Laboratory, National Microbiology Center, Institute of Health Carlos III, Madrid, Spain
| | - Agustín Benito
- National Center for Tropical Medicine, Institute of Health Carlos III, Madrid, Spain
- Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
| | - Anacleto Sima
- National Program for Onchocerciasis and other Filariasis Control, Ministry of Health, Malabo, Equatorial Guinea
| | - Pilar Aparicio
- National Center for Tropical Medicine, Institute of Health Carlos III, Madrid, Spain
- Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
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Lupi O, Downing C, Lee M, Pino L, Bravo F, Giglio P, Sethi A, Klaus S, Sangueza OP, Fuller C, Mendoza N, Ladizinski B, Woc-Colburn L, Tyring SK. Mucocutaneous manifestations of helminth infections: Nematodes. J Am Acad Dermatol 2016; 73:929-44; quiz 945-6. [PMID: 26568337 DOI: 10.1016/j.jaad.2014.11.034] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 11/06/2014] [Accepted: 11/17/2014] [Indexed: 11/30/2022]
Abstract
In the 21st century, despite increased globalization through international travel for business, medical volunteerism, pleasure, and immigration/refugees into the United States, there is little published in the dermatology literature regarding the cutaneous manifestations of helminth infections. Approximately 17% of travelers seek medical care because of cutaneous disorders, many related to infectious etiologies. This review will focus on the cutaneous manifestations of helminth infections and is divided into 2 parts: part I focuses on nematode infections, and part II focuses on trematode and cestode infections. This review highlights the clinical manifestations, transmission, diagnosis, and treatment of helminth infections. Nematodes are roundworms that cause diseases with cutaneous manifestations, such as cutaneous larval migrans, onchocerciasis, filariasis, gnathostomiasis, loiasis, dracunculiasis, strongyloidiasis, ascariasis, streptocerciasis, dirofilariasis, and trichinosis. Tremadotes, also known as flukes, cause schistosomiasis, paragonimiasis, and fascioliasis. Cestodes (tapeworms) are flat, hermaphroditic parasites that cause diseases such as sparganosis, cysticercosis, and echinococcus.
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Affiliation(s)
- Omar Lupi
- Federal University of the State of Rio de Janeiro and Policlinica Geral do Rio de Janeiro, Rio de Janerio, Brazil
| | - Christopher Downing
- Department of Dermatology, University of Texas Health Science Center, Houston, Texas.
| | - Michael Lee
- Department of Dermatology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Livia Pino
- Federal University of the State of Rio de Janeiro and Policlinica Geral do Rio de Janeiro, Rio de Janerio, Brazil
| | - Francisco Bravo
- Instituto de Medicina Tropical Alexander von Humboldt, Lima, Peru; Universidad Peruana Cayetano Heredia, Lima, Peru
| | | | - Aisha Sethi
- Section of Infectious Diseases and Global Health, Department of Dermatology, University of Chicago, Chicago, Illinois
| | - Sidney Klaus
- Department of Dermatology, Dartmouth School of Medicine, Hanover, New Hampshire
| | - Omar P Sangueza
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina; Department of Dermatology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Claire Fuller
- International Foundation for Dermatology and Consultant, Chelsea and Westminster Hospital, London, United Kingdom
| | - Natalia Mendoza
- Department of Dermatology, University of Texas Health Science Center, Houston, Texas
| | - Barry Ladizinski
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Laila Woc-Colburn
- National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas
| | - Stephen K Tyring
- Center for Clinical Studies, Houston, Texas; Department of Dermatology, University of Texas Health Science Center, Houston, Texas
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Modelling the Spread of River Blindness Disease via the Caputo Fractional Derivative and the Beta-derivative. ENTROPY 2016. [DOI: 10.3390/e18020040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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O’Hanlon SJ, Slater HC, Cheke RA, Boatin BA, Coffeng LE, Pion SDS, Boussinesq M, Zouré HGM, Stolk WA, Basáñez MG. Model-Based Geostatistical Mapping of the Prevalence of Onchocerca volvulus in West Africa. PLoS Negl Trop Dis 2016; 10:e0004328. [PMID: 26771545 PMCID: PMC4714852 DOI: 10.1371/journal.pntd.0004328] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 12/04/2015] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND The initial endemicity (pre-control prevalence) of onchocerciasis has been shown to be an important determinant of the feasibility of elimination by mass ivermectin distribution. We present the first geostatistical map of microfilarial prevalence in the former Onchocerciasis Control Programme in West Africa (OCP) before commencement of antivectorial and antiparasitic interventions. METHODS AND FINDINGS Pre-control microfilarial prevalence data from 737 villages across the 11 constituent countries in the OCP epidemiological database were used as ground-truth data. These 737 data points, plus a set of statistically selected environmental covariates, were used in a Bayesian model-based geostatistical (B-MBG) approach to generate a continuous surface (at pixel resolution of 5 km x 5km) of microfilarial prevalence in West Africa prior to the commencement of the OCP. Uncertainty in model predictions was measured using a suite of validation statistics, performed on bootstrap samples of held-out validation data. The mean Pearson's correlation between observed and estimated prevalence at validation locations was 0.693; the mean prediction error (average difference between observed and estimated values) was 0.77%, and the mean absolute prediction error (average magnitude of difference between observed and estimated values) was 12.2%. Within OCP boundaries, 17.8 million people were deemed to have been at risk, 7.55 million to have been infected, and mean microfilarial prevalence to have been 45% (range: 2-90%) in 1975. CONCLUSIONS AND SIGNIFICANCE This is the first map of initial onchocerciasis prevalence in West Africa using B-MBG. Important environmental predictors of infection prevalence were identified and used in a model out-performing those without spatial random effects or environmental covariates. Results may be compared with recent epidemiological mapping efforts to find areas of persisting transmission. These methods may be extended to areas where data are sparse, and may be used to help inform the feasibility of elimination with current and novel tools.
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Affiliation(s)
- Simon J. O’Hanlon
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary’s Campus), Imperial College London, London, United Kingdom
| | - Hannah C. Slater
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary’s Campus), Imperial College London, London, United Kingdom
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Robert A. Cheke
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary’s Campus), Imperial College London, London, United Kingdom
- Natural Resources Institute, University of Greenwich at Medway, Chatham, Kent, United Kingdom
| | - Boakye A. Boatin
- Lymphatic Filariasis Support Centre, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Luc E. Coffeng
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sébastien D. S. Pion
- UMI 233, Institut de Recherche pour le Développement (IRD) and University of Montpellier 1, Montpellier, France
| | - Michel Boussinesq
- UMI 233, Institut de Recherche pour le Développement (IRD) and University of Montpellier 1, Montpellier, France
| | - Honorat G. M. Zouré
- African Programme for Onchocerciasis Control (APOC), World Health Organization (WHO), Ouagadougou, Burkina Faso
| | - Wilma A. Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - María-Gloria Basáñez
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary’s Campus), Imperial College London, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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Kobayashi T, Hayakawa K, Mawatari M, Itoh M, Akao N, Yotsu RR, Sugihara J, Takeshita N, Kutsuna S, Fujiya Y, Kanagawa S, Ohmagari N, Kato Y. Loiasis in a Japanese Traveler Returning from Central Africa. Trop Med Health 2015; 43:149-53. [PMID: 26161033 PMCID: PMC4491493 DOI: 10.2149/tmh.2015-05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/04/2015] [Indexed: 11/11/2022] Open
Abstract
We encountered a probable case of loiasis in a returned traveler from Central Africa. A 52-year-old Japanese woman presented to our hospital complaining of discomfort in her eyes and skin. She reported having frequently visited Central Africa over many years and having been extensively exposed to the rainforest climate and ecosystem. Although no microfilariae were found in her blood, there was an elevated level of IgG antibodies against the crude antigens of Brugia pahangi, which have cross-reactivity with Loa loa. She was treated with albendazole for 21 days, after which the antigen-specific IgG level decreased and no relapse occurred.
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Affiliation(s)
- Tetsuro Kobayashi
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Kayoko Hayakawa
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Momoko Mawatari
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Makoto Itoh
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine , Aichi, Japan
| | - Nobuaki Akao
- Department of Environmental Parasitology, Graduate School of Tokyo Medical and Dental University , Tokyo, Japan
| | - Rie R Yotsu
- Department of Dermatology, National Center for Global Health and Medicine , Tokyo, Japan ; National Suruga Sanatorium , Shizuoka, Japan
| | - Jun Sugihara
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Nozomi Takeshita
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Satoshi Kutsuna
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Yoshihiro Fujiya
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Shuzo Kanagawa
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Norio Ohmagari
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
| | - Yasuyuki Kato
- Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo, Japan
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Baum S, Greenberger S, Pavlotsky F, Solomon M, Enk CD, Schwartz E, Barzilai A. Late-onset onchocercal skin disease among Ethiopian immigrants. Br J Dermatol 2014; 171:1078-83. [PMID: 24673403 DOI: 10.1111/bjd.13005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2014] [Indexed: 11/27/2022]
Abstract
BACKGROUND Onchocerciasis is an infectious disease caused by the filaria Onchocerca volvulus. Very little is known regarding onchocerciasis imported from endemic to nonendemic areas. OBJECTIVES To evaluate pruritic dermatitis simulating atopic dermatitis in Ethiopian immigrants in Israel. PATIENTS AND METHODS A retrospective study of 27 Ethiopian immigrants to Israel was conducted. Demographics and clinical and laboratory data were collected. RESULTS Of the group of 27 patients, 10 (37%) were men and 17 (63%) were women. The average age at referral was 29 years. All of the patients emigrated from Kuwara, Ethiopia. Diagnosis was done by either positive skin snip test or immunoglobulin (Ig) G4 serology of onchocerciasis in 14 patients. The most common presentation was a combination of lichenified onchodermatitis with atrophy and depigmentation (36%). Eosinophilia and elevated IgE levels were common. Seventeen patients were treated with a single administration of oral ivermectin 200 μg mg(-1). Thirteen patients responded to the treatment. CONCLUSIONS Immigrants from endemic regions to developed countries presenting with pruritic diseases, especially those with a clinical picture suggestive of atopic dermatitis, should be evaluated for possible onchocerciasis infection. Ivermectin, a relatively safe and low-cost treatment, should be considered even in the absence of a proven disease. Physicians should have a high index of suspicion in patients with the corresponding residential history.
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Affiliation(s)
- S Baum
- Department of Dermatology, Chaim Sheba Medical Center, Tel Hashomer, Israel; The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Makenga Bof JC, Maketa V, Bakajika DK, Ntumba F, Mpunga D, Murdoch ME, Hopkins A, Noma MM, Zouré H, Tekle AH, Katabarwa MN, Lutumba P. Onchocerciasis control in the Democratic Republic of Congo (DRC): challenges in a post-war environment. Trop Med Int Health 2014; 20:48-62. [PMID: 25302560 DOI: 10.1111/tmi.12397] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To evaluate onchocerciasis control activities in the Democratic Republic of Congo (DRC) in the first 12 years of community-directed treatment with ivermectin (CDTI). METHODS Data from the National Programme for Onchocerciasis (NPO) provided by the National Onchocerciasis Task Force (NOTF) through the annual reports of the 21 CDTI projects for the years 2001-2012 were reviewed retrospectively. A hypothetical-inputs-process-outputs-outcomes table was constructed. RESULTS Community-directed treatment with ivermectin expanded from 1968 communities in 2001 to 39 100 communities by 2012 while the number of community-directed distributors (CDD) and health workers (HW) multiplied. By 2012, there were ratios of 1 CDD per 262 persons and 1 HW per 2318 persons at risk. More than 80% of the funding came from the fiduciary funds of the African Programme for Onchocerciasis Control. The cost of treatment per person treated fell from US$ 1.1 in 2001 to US$ 0.1 in 2012. The therapeutic coverage increased from 2.7% (2001) to 74.2% (2012); the geographical coverage, from 4.7% (2001) to 93.9% (2012). Geographical coverage fell in 2005 due to deaths in loiasis co-endemic areas, and the therapeutic coverage fell in 2008 due to insecurity. CONCLUSIONS Challenges to CDTI in DRC have been serious adverse reactions to ivermectin in loiasis co-endemic areas and political conflict. Targets for personnel or therapeutic and geographical coverages were not met. Longer term funding and renewed efforts are required to achieve control and elimination of onchocerciasis in DRC.
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Affiliation(s)
- J-C Makenga Bof
- Faculty of Public Health, Université Catholique de Louvain, Brussels, Belgium
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Turner HC, Walker M, Churcher TS, Basáñez MG. Modelling the impact of ivermectin on River Blindness and its burden of morbidity and mortality in African Savannah: EpiOncho projections. Parasit Vectors 2014; 7:241. [PMID: 24886747 PMCID: PMC4037555 DOI: 10.1186/1756-3305-7-241] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 05/19/2014] [Indexed: 11/17/2022] Open
Abstract
Background The African Programme for Onchocerciasis Control (APOC) has refocused its goals on the elimination of infection where possible, seemingly achievable by 15–17 years of annual mass distribution of ivermectin in some African foci. Previously, APOC had focused on the elimination of onchocerciasis as a public health problem. Timeframes have been set by the World Health Organization, the London Declaration on Neglected Tropical Diseases and the World Bank to achieve these goals by 2020–2025. Methods A novel mathematical model of the dynamics of onchocercal disease is presented which links documented associations between Onchocerca volvulus infection and the prevalence and incidence of morbidity and mortality to model outputs from our host age- and sex-structured onchocerciasis transmission framework (EpiOncho). The model is calibrated for African savannah settings, and used to assess the impact of long-term annual mass administration of ivermectin on infection and ocular and skin disease and to explore how this depends on epidemiological and programmatic variables. Results Current onchocerciasis disease projections, which do not account for excess mortality of sighted individuals with heavy microfilarial loads, underestimate disease burden. Long-term annual ivermectin treatment is highly effective at reducing both the morbidity and mortality associated with onchocerciasis, and this result is not greatly influenced by treatment coverage and compliance. By contrast, impact on microfilarial prevalence and intensity is highly dependent on baseline endemicity, treatment coverage and systematic non-compliance. Conclusions The goals of eliminating morbidity and infection with ivermectin alone are distinctly influenced by epidemiological and programmatic factors. Whilst the former goal is most certainly achievable, reaching the latter will strongly depend on initial endemicity (the higher the endemicity, the greater the magnitude of inter-treatment transmission), advising caution when generalising the applicability of successful elimination outcomes to other areas. The proportion of systematic non-compliers will become far more influential in terms of overall success in achieving elimination goals.
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Affiliation(s)
- Hugo C Turner
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St, Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK.
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Knowledge and beliefs about onchocerciasis among rural inhabitants in an endemic area of Ethiopia. Int Health 2013; 2:59-64. [PMID: 24037052 DOI: 10.1016/j.inhe.2009.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A cross-sectional study was conducted to assess the knowledge and beliefs about causes, transmission, prevention and control of onchocerciasis among rural inhabitants in an endemic area of Ethiopia. Descriptive and quantitative information was collected using focus group discussions and a pretested structured questionnaire. Onchocerciasis affected and unaffected respondents' knowledge and beliefs regarding onchocerciasis were compared. Overall, 75.9% (192/253) of study subjects were aware about onchocerciasis. During the survey, 66.9% of affected, and 45.5% of unaffected respondents knew that onchocerciasis was transmitted through blackfly bites. About 53% of unaffected and 60% of affected respondents thought that onchocerciasis was preventable and the majority of the affected respondents felt that it was curable. Chi-square statistical analysis found a significant association between affected and unaffected individual's knowledge and beliefs about causes, transmission, prevention and control of onchocerciasis. Although the majority of respondents had ample awareness, a sizable proportion still had misconceptions and misunderstandings about causes, transmission, prevention and control of onchocerciasis. Therefore, appropriate communication strategies should be developed to create the awareness regarding the role of blackflies in onchocerciasis transmission, the importance of proper prevention techniques, early diagnosis and treatment to bring a constructive outcome in the near future.
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Osue HO, Inabo HI, Yakubu SE, Audu PA, Galadima M, Odama LE, Musa D, Ado SA, Mamman M. Impact of Eighteen-Year Varied Compliance to Onchocerciasis Treatment with Ivermectin in Sentinel Savannah Agrarian Communities in Kaduna State of Nigeria. ISRN PARASITOLOGY 2013; 2013:960168. [PMID: 27398386 PMCID: PMC4890928 DOI: 10.5402/2013/960168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 06/02/2013] [Indexed: 11/30/2022]
Abstract
Baseline and impact assessment data were generated in 1994 (n = 532) and 2011 (n = 593) from 6 sentinel villages with generalized onchocerciasis. Only volunteers and a cohort (n = 445, 75%) were screened at both visits. Each village had received 11 (64.7%) annual treatments and 92.6%, range 88.7-100%, treatment compliance. Overall mean number of treatment was 2.9 ± 1.6 with a range 2.0 ± 1.2-3.3 ± 0.6. Significant decreases in skin microfilaria prevalence from 201 (38%) to 0 (0%), palpable nodule from 77 (15%) to 4 (0.7%), dermal changes from 51 (9.6%) to 2 (0.04%), optic nerve disease from 24 (4.5%) to 4 (2.0%), and onchocercal inducible ocular lesions from 31 (5.8%) to 12 (2.0%) were recorded, P < 0.05, (t-test of unpaired data). Cases of glaucoma, 8 (1.4%), and blindness, 6 (1.05%), remained unchanged. Visual acuity ≥6/24 in one or both eyes, 198 (33.45%); cataract, 169 (28.5%); pterygium 157 (26.5%); and acute senilis, 165 (27.9%), were significantly increased and positively correlated with increase in age (R (2) = 0.898 - 0.949). Dissected parous Simulium damnosum caught (n = 222) were without infective third stage larva. Active onchocerciasis transmission seems halted despite varied compliance to long-term ivermectin treatment. We recommend continued surveillance and targeted treatment of controlled and hypoendemic areas.
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Affiliation(s)
- Hudu O. Osue
- Nigeria Institute for Trypanosomiasis Research (NITR), P. M. B. 2077, Kaduna 800001, Nigeria
| | - Helen I. Inabo
- Department of Microbiology, Faculty of Science, Ahmadu Bello University (ABU), Zaria, Kaduna State, Nigeria
| | - Sabo E. Yakubu
- Department of Microbiology, Faculty of Science, Ahmadu Bello University (ABU), Zaria, Kaduna State, Nigeria
| | - Patrick A. Audu
- Department of Biological Sciences, ABU, Zaria, Kaduna State 810000, Nigeria
| | - Musa Galadima
- Department of Microbiology, Faculty of Science, Federal University of Technology, Minna, Niger State 920001, Nigeria
| | - Lillian E. Odama
- National Institute for Pharmaceutical Research and Development (NIPRD), Idun, Abuja 900102, Nigeria
| | - Danjuma Musa
- Nigeria Institute for Trypanosomiasis Research (NITR), P. M. B. 2077, Kaduna 800001, Nigeria
| | - Saleh A. Ado
- Department of Microbiology, Faculty of Science, Ahmadu Bello University (ABU), Zaria, Kaduna State, Nigeria
| | - Mohammed Mamman
- Nigeria Institute for Trypanosomiasis Research (NITR), P. M. B. 2077, Kaduna 800001, Nigeria
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Amazigo UV, Nnoruka E, Maduka C, Bump J, Benton B, Sékétéli A. Ivermectin improves the skin condition and self-esteem of females with onchocerciasis: a report of two cases. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2013; 98:533-7. [PMID: 15257804 DOI: 10.1179/000349804225003505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- U V Amazigo
- African Programme for Onchocerciasis Control (APOC), 01 B. P. 549, Ouagadougou, Burkina Faso.
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Higazi TB, Zarroug IMA, Mohamed HA, Elmubark WA, Deran TCM, Aziz N, Katabarwa M, Hassan HK, Unnasch TR, Mackenzie CD, Richards F, Hashim K. Interruption of Onchocerca volvulus transmission in the Abu Hamed focus, Sudan. Am J Trop Med Hyg 2013; 89:51-7. [PMID: 23690554 PMCID: PMC3748488 DOI: 10.4269/ajtmh.13-0112] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 04/09/2013] [Indexed: 11/07/2022] Open
Abstract
Abu Hamed, Sudan, the northernmost location of onchocerciasis in the world, began community-directed treatment with ivermectin (CDTI) in 1998, with annual treatments enhanced to semiannual in 2007. We assessed the status of the parasite transmission in 2011 entomologically, parasitologically, and serologically. O-150 pool screening showed no parasite DNA in 17,537 black flies collected in 2011 (95% confidence interval upper limit [95% CI UL] = 0.023). Skin microfilariae, nodules, and signs of skin disease were absent in 536 individuals in seven local communities. Similarly, no evidence of Onchocerca volvulus Ov16 antibodies was found in 6,756 school children ≤ 10 years (95% CI UL = 0.03%). Because this assessment of the focus meets the 2001 World Health Organization (WHO) criteria for interrupted transmission, treatment was halted in 2012, and a post-treatment surveillance period was initiated in anticipation of declaration of disease elimination in this area. We provide the first evidence in East Africa that long-term CDTI alone can interrupt transmission of onchocerciasis.
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Affiliation(s)
- Tarig B Higazi
- Department of Biological Sciences, Ohio University, Zanesville, OH, USA.
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Kurosinski MA, Lüersen K, Ndjonka D, Younis AE, Brattig NW, Liebau E. Filarial parasites possess an antizyme but lack a functional ornithine decarboxylase. Acta Trop 2013; 126:167-76. [PMID: 23474393 DOI: 10.1016/j.actatropica.2013.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 02/08/2013] [Accepted: 02/11/2013] [Indexed: 10/27/2022]
Abstract
In eukaryotes, the key player in polyamine metabolism is the ornithine decarboxylase (ODC) that catalyses the first and rate limiting step in cellular polyamine synthesis. The half life of ODC is strictly regulated by the antizyme (AZ), which promotes its degradation. Older reports on the polyamine situation in filarial parasites indicate a lack of ornithine decarboxylation activity and an increased uptake of polyamines. Our in silico analysis of the Brugia malayi genome revealed only an ODC-like protein that lacks essential residues. Consequently, the recombinant protein had no enzymatic ODC activity. Furthermore, only ODC-like genes were found in the available draft genomes of other filarial parasites. In this ODC-free scenario, we set out to investigate the AZ of O. volvulus (OvAZ). The expression of the recombinant protein allowed us to analyse the localization of OvAZ in different O. volvulus stages as well as to identify it as target for the human humoral immune response. Strong immunostaining was observed in the outer zone of the uterine epithelium as well as in the uterus lumen around the periphery of the developing parasite, indicating a potential role of the OvAZ in the control of polyamine levels during embryonic development. By employing a novel in vivo method using Caenorhabditis elegans, we postulate that the OvAZ enters the secretory pathway. Even though the ODCs are absent in filarial parasites, OvAZ has the ability to bind to various ODCs, thereby demonstrating the functionality of the conserved AZ-binding domains. Finally, pull-down assays show an interaction between B. malayi AZ and the B. malayi ODC-like protein, indicating that the B. malayi ODC-like protein might function as an AZI. Taken together, our results suggest that filarial species do not possess the ODC while retaining the ODC-regulatory proteins AZ and AZI. It is tempting to speculate that both proteins are retained for the regulation of polyamine transport systems.
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