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Lakwo T, Oguttu D, Ukety T, Post R, Bakajika D. Onchocerciasis Elimination: Progress and Challenges. Res Rep Trop Med 2020; 11:81-95. [PMID: 33117052 PMCID: PMC7548320 DOI: 10.2147/rrtm.s224364] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 08/16/2020] [Indexed: 01/08/2023] Open
Abstract
Onchocerciasis is a parasitic infection caused by the filarial nematode Onchocerca volvulus and transmitted through the bites of black flies of the genus Similium that breed in rivers and streams. The impact of mass treatment with ivermectin and supplemented by vector control in some countries has changed the global scene of onchocerciasis. There has been reported progress made in elimination of onchocerciasis in central and southern American countries and in some localities in Africa. The target for elimination in the Americas has been set at 2022 while for 12 countries in Africa this is expected in 2030. This review was conducted to examine the current status of onchocerciasis elimination at the global level and report on progress made. Literature searches were made through PubMed, articles in English or English abstracts, reports and any other relevant articles related to the subject. The global burden of onchocerciasis is progressively reducing and is no longer a public health problem in some regions. However, programs are challenged with a range of issues: cross-border transmission, diagnostic tools, Loa loa co-endemicity, limited workforce in entomology and maintaining enthusiasm among community drug distributors. More concerted effort using appropriate tools is required to overcome the challenges.
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Affiliation(s)
- Thomson Lakwo
- Neglected Tropical Disease Control Program, Vector Control Division, Ministry of Health, Kampala, Uganda
| | - David Oguttu
- Neglected Tropical Disease Control Program, Vector Control Division, Ministry of Health, Kampala, Uganda
| | - Tony Ukety
- Centre de Recherche pour les Maladies Tropicales, Rethy, Ituri Province, The Democratic Republic of the Congo
| | - Rory Post
- Disease Control Department, London School of Hygiene & Tropical Medicine, London, UK.,School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK
| | - Didier Bakajika
- Expanded Special Project for Elimination of Neglected Tropical Diseases, WHO Regional Office for Africa, Brazzaville, Congo
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Fernández-Santos NA, Unnasch TR, Rodríguez-Luna IC, Prado-Velasco FG, Adeniran AA, Martínez-Montoya H, Rodríguez-Pérez MA. Post-elimination surveillance in formerly onchocerciasis endemic focus in Southern Mexico. PLoS Negl Trop Dis 2020; 14:e0008008. [PMID: 31999704 PMCID: PMC7012445 DOI: 10.1371/journal.pntd.0008008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 02/11/2020] [Accepted: 12/19/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND All formerly endemic communities of the Southern Chiapas focus of onchocerciasis in Mexico were treated with ivermectin until parasite transmission was eliminated by 2015. Transmission of onchocerciasis did not resume during a period of three years (2012-2014) following the final distribution of ivermectin in 2011; it was thus concluded that transmission remained undetectable without intervention. WHO thus declared the elimination of transmission of onchocerciasis from Mexico in 2015. METHODOLOGY/PRINCIPAL FINDINGS From 2016 to the present, post-elimination surveillance (PES) based on examination for suspected onchocercomas was performed in the former Southern Chiapas focus. Each year, over 60% of the total population (range = 85,347-104,106 individuals) of the formerly endemic communities were examined for onchocercomas. Thirty-four individuals were found harboring suspected onchocercomas in the PES surveys conducted from 2016-2019. Of these, one female of 7 years of age who had immigrated from a formerly endemic focus, harbored an infertile (sterile) female in the suspected onchocercoma; all others were negative. Skin biopsy assessments were performed from March through May 2017 in three communities where the female resided. None of the 83 individuals of the three communities examined by skin biopsy were mf positive. Similarly, none of the biopsies from the individuals were found to contain parasite DNA when tested by polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA). CONCLUSIONS/SIGNIFICANCE These provide support to the conclusion that onchocerciasis has been eliminated from Mexico.
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Affiliation(s)
| | - Thomas R. Unnasch
- Center for Global Health Infectious Diseases Research, University of South Florida, Tampa, Florida, United States of America
| | | | | | - Adebiyi A. Adeniran
- Instituto Politécnico Nacional, Centro de Biotecnología Genómica, Reynosa, Tamaulipas, México
| | - Humberto Martínez-Montoya
- Unidad Académica Multidisciplinaria Reynosa Aztlan—Universidad Autónoma de Tamaulipas, Reynosa, Tamaulipas, México
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Richards FO, Nwoke BEB, Zarroug I, Tukahebwa E, Negussu N, Higazi TB, Oguttu D, Tadesse Z, Miri E, Aziz N, Habomugisha P, Katabarwa M. The positive influence the Onchocerciasis Elimination Program for the Americas has had on Africa programs. Infect Dis Poverty 2019; 8:52. [PMID: 31303175 PMCID: PMC6628490 DOI: 10.1186/s40249-019-0558-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 05/28/2019] [Indexed: 01/28/2023] Open
Abstract
A recent article “Is onchocerciasis elimination in Africa feasible by 2025: a perspective based on lessons learnt from the African control programmes” in Infectious Diseases of Poverty claimed that undue influence on African programs by concepts developed by the Onchocerciasis Elimination Program of the Americas (OEPA) is detrimental to stopping mass drug administration (MDA) in Africa. This claim is made despite a record year for MDA stoppage in four African countries of > 3.5 million treatments in 2018, far exceeding any past OEPA or African Program for Onchocerciasis Control (APOC) stop MDA success.
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Affiliation(s)
- Frank O Richards
- The Carter Center, One Copenhill Avenue, 453 Freedom Parkway, Atlanta, GA, 30307, USA.
| | - B E B Nwoke
- Imo State University Owerri, PMB 2000, Owerri, Nigeria
| | - Isam Zarroug
- Sudan Ministry of Health, P.O. Box 303, Khartoum, Sudan
| | - Edridah Tukahebwa
- Uganda Ministry of Health, 15 Bombo Rd., P. O. Box 1661, Kampala, Uganda
| | - Nebiyu Negussu
- Ethiopia Federal Ministry of Health, P. O. Box 1234, Addis Ababa, Ethiopia
| | - T B Higazi
- Ohio University, 1425 Newark Rd, Zanesville, OH, 43701, USA
| | - David Oguttu
- Uganda Ministry of Health, 15 Bombo Rd., P. O. Box 1661, Kampala, Uganda
| | - Zerihun Tadesse
- The Carter Center-Ethiopia, P. O. Box 13373, Bole K. K. Kebele 05, Addis Ababa, Ethiopia
| | - Emmanuel Miri
- The Carter Center-Nigeria, No. 1 Jeka Kadima St, Jos, Plateau State, Nigeria
| | - Nabil Aziz
- The Carter Center-Sudan, P. O. Box 48, Khartoum, Sudan
| | | | - Moses Katabarwa
- The Carter Center, One Copenhill Avenue, 453 Freedom Parkway, Atlanta, GA, 30307, USA
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Sauerbrey M, Rakers LJ, Richards FO. Progress toward elimination of onchocerciasis in the Americas. Int Health 2019; 10:i71-i78. [PMID: 29471334 DOI: 10.1093/inthealth/ihx039] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 11/30/2017] [Indexed: 11/14/2022] Open
Abstract
The Onchocerciasis Elimination Program for the Americas (OEPA) is a regional initiative and international partnership that has made considerable progress toward its goal since it was launched in 1993. Its strategy is based on mass drug administration of ivermectin (Mectizan, donated by MSD, also known as Merck & Co., Inc., Kenilworth, NJ, USA), twice or four times per year, with at least 85% coverage of eligible populations. From 1989 to 2016, 11 741 276 ivermectin treatments have been given in the Americas, eliminating transmission in 11 of 13 foci. The OEPA's success has had a great influence on programs in Africa, especially Sudan and Uganda, which moved from a control to an elimination strategy in 2006 and 2007, respectively. The successes in the Americas have also greatly influenced WHO guidelines for onchocerciasis transmission elimination. With four of the six originally endemic American countries now WHO verified as having eliminated onchocerciasis transmission, and 95% of ivermectin treatments in the region halted, the regional focus is now on the remaining active transmission zone, called the Yanomami Area, on the border between Venezuela and Brazil. Both countries have difficult political climates that hinder the elimination task in this remote and relatively neglected region. As with other elimination efforts, 'the final inch' is often the most difficult task of all.
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Affiliation(s)
- Mauricio Sauerbrey
- Onchocerciasis Elimination Program for the Americas, Guatemala City, Guatemala
| | - Lindsay J Rakers
- Carter Center, One Copenhill, 453 Freedom Parkway, Atlanta, GA 30307, USA
| | - Frank O Richards
- Carter Center, One Copenhill, 453 Freedom Parkway, Atlanta, GA 30307, USA
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Nicholls RS, Duque S, Olaya LA, López MC, Sánchez SB, Morales AL, Palma GI. Elimination of onchocerciasis from Colombia: first proof of concept of river blindness elimination in the world. Parasit Vectors 2018; 11:237. [PMID: 29642939 PMCID: PMC5896109 DOI: 10.1186/s13071-018-2821-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/26/2018] [Indexed: 11/22/2022] Open
Abstract
Background Onchocerciasis is a chronic parasitic infection originally endemic in 13 discrete regional foci distributed among six countries of Latin America (Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela). In Colombia, this disease was discovered in 1965 in the Pacific Coast of the country. The National Onchocerciasis Elimination Program was established in 1993 with the aim of eliminating disease morbidity and infection transmission. In 2013, the World Health Organization (WHO) verified Colombia as free of onchocerciasis, becoming the first country in the world to reach such a goal. This report provides the empirical evidence of the elimination of Onchocerca volvulus transmission by Simulium exiguum (s.l.) after 12 years of 6-monthly mass drug administration of Mectizan® (ivermectin) to all the eligible residents living in this endemic area. Methods From 1996 onwards, a biannual community-based mass ivermectin administration programme was implemented, complemented by health education and community participation. In-depth parasitological, serological and entomological surveys were conducted periodically between 1998 and 2007 to evaluate the impact of ivermectin treatment according to the 2001 WHO guidelines. When the interruption of parasite transmission was demonstrated, the drug distribution ceased and a three-year post-treatment surveillance (PTS) period (2008–2010) was initiated. Results After 23 rounds of treatment, parasitological and ophthalmological assessments showed absence of microfilariae in skin and anterior chamber of the eyes. Serological tests proved lack of antibodies against O. volvulus in children under 10 years-old. A total of 10,500 S. exiguum flies tested by PCR had no L3 infection (infectivity rate = 0.0095%; 95% CI: 0.0029–0.049) during 2004, indicating interruption of parasite transmission. However, biannual ivermectin treatments continued until 2007 followed by a 3-year PTS period at the end of which 13,481 flies were analyzed and no infective flies were found (infectivity rate = 0%; 95% CI: 0.0–0.014). Conclusions These results fulfilled the WHO criteria for onchocerciasis elimination. Consequently, in 2013 Colombia was verified as free of onchocerciasis, demonstrating that elimination of this neglected tropical disease is an achievable goal and paving the way for an elimination agenda to be followed by other endemic countries in Latin America and Africa.
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Affiliation(s)
- Rubén Santiago Nicholls
- Grupo de Parasitología, Instituto Nacional de Salud, Avenida Calle 26 No. 51-20, Bogotá, DC CP 111321, Colombia.
| | - Sofía Duque
- Grupo de Parasitología, Instituto Nacional de Salud, Avenida Calle 26 No. 51-20, Bogotá, DC CP 111321, Colombia
| | - Luz Adriana Olaya
- Laboratorio Departamental de Salud Pública, Secretaría Departamental de Salud del Cauca, Calle 5 No. 15-57, Popayán, Cauca, CP 190003, Colombia
| | - Myriam Consuelo López
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia, Ciudad Universitaria, Bogotá, DC CP 111321, Colombia
| | - Sol Beatriz Sánchez
- Consultant Health Education, Colombian Onchocerciasis Elimination Program, Carrera 93 # 16-90, Cali, CP 760032, Colombia
| | - Alba Lucía Morales
- Onchocerciasis Elimination Program for the Americas (OEPA), 14 calle 3-51, zona 10, Edificio Murano Center, CP 01010, Guatemala, Guatemala
| | - Gloria Inés Palma
- Departamento de Microbiologia, Facultad de Salud, Universidad del Valle, Campus San Fernando, Calle 4B No. 36-00, CP 760043, Cali, Colombia
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Botto C, Basañez MG, Escalona M, Villamizar NJ, Noya-Alarcón O, Cortez J, Vivas-Martínez S, Coronel P, Frontado H, Flores J, Graterol B, Camacho O, Tovar Y, Borges D, Morales AL, Ríos D, Guerra F, Margeli H, Rodriguez MA, Unnasch TR, Grillet ME. Evidence of suppression of onchocerciasis transmission in the Venezuelan Amazonian focus. Parasit Vectors 2016; 9:40. [PMID: 26813296 PMCID: PMC4728794 DOI: 10.1186/s13071-016-1313-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 01/11/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The World Health Organization (WHO) has set goals for onchocerciasis elimination in Latin America by 2015. Most of the six previously endemic countries are attaining this goal by implementing twice a year (and in some foci, quarterly) mass ivermectin (Mectizan®) distribution. Elimination of transmission has been verified in Colombia, Ecuador and Mexico. Challenges remain in the Amazonian focus straddling Venezuela and Brazil, where the disease affects the hard-to-reach Yanomami indigenous population. We provide evidence of suppression of Onchocerca volvulus transmission by Simulium guianense s.l. in 16 previously hyperendemic Yanomami communities in southern Venezuela after 15 years of 6-monthly and 5 years of 3-monthly mass ivermectin treatment. METHODS Baseline and monitoring and evaluation parasitological, ophthalmological, entomological and serological surveys were conducted in selected sentinel and extra-sentinel communities of the focus throughout the implementation of the programme. RESULTS From 2010 to 2012-2015, clinico-parasitological surveys indicate a substantial decrease in skin microfilarial prevalence and intensity of infection; accompanied by no evidence (or very low prevalence and intensity) of ocular microfilariae in the examined population. Of a total of 51,341 S. guianense flies tested by PCR none had L3 infection (heads only). Prevalence of infective flies and seasonal transmission potentials in 2012-2013 were, respectively, under 1% and 20 L3/person/transmission season. Serology in children aged 1-10 years demonstrated that although 26 out of 396 (7%) individuals still had Ov-16 antibodies, only 4/218 (2%) seropositives were aged 1-5 years. CONCLUSIONS We report evidence of recent transmission and morbidity suppression in some communities of the focus representing 75% of the Yanomami population and 70% of all known communities. We conclude that onchocerciasis transmission could be feasibly interrupted in the Venezuelan Amazonian focus.
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Affiliation(s)
- Carlos Botto
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - María-Gloria Basañez
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, Faculty of Medicine (St Mary's campus), Imperial College London, London, UK.
| | - Marisela Escalona
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Néstor J Villamizar
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Oscar Noya-Alarcón
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
- Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela.
| | - José Cortez
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Sarai Vivas-Martínez
- Cátedra de Salud Pública. Facultad de Medicina (Escuela Luis Razetti), Universidad Central de Venezuela, Caracas, Venezuela.
| | - Pablo Coronel
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Hortencia Frontado
- Instituto de Altos Estudios "Dr. Arnoldo Gabaldón", Ministerio del Poder Popular para la Salud, Maracay, Estado Aragua, Venezuela.
| | - Jorge Flores
- Instituto Geográfico de Venezuela "Simón Bolívar", Caracas, Venezuela.
| | - Beatriz Graterol
- Instituto Nacional de Investigaciones Agrícolas, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Oneida Camacho
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Yseliam Tovar
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Daniel Borges
- Centro Amazónico de Investigación y Control de Enfermedades Tropicales Servicio Autónomo CAICET, Ministerio del Poder Popular para la Salud, Puerto Ayacucho, Estado Amazonas, Venezuela.
| | - Alba Lucia Morales
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala.
| | - Dalila Ríos
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala.
| | - Francisco Guerra
- Instituto Geográfico de Venezuela "Simón Bolívar", Caracas, Venezuela.
| | - Héctor Margeli
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala.
| | | | - Thomas R Unnasch
- Department of Global Health, University of South Florida, Tampa, FL, USA.
| | - María Eugenia Grillet
- Laboratorio de Biología de Vectores y Parásitos, Instituto de Zoología y Ecología Tropical, Facultad de Ciencias, Universidad Central de Venezuela, Apartado Postal 47072, Caracas, 1041-A, Venezuela.
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Basáñez M, Walker M, Turner H, Coffeng L, de Vlas S, Stolk W. River Blindness: Mathematical Models for Control and Elimination. ADVANCES IN PARASITOLOGY 2016; 94:247-341. [PMID: 27756456 DOI: 10.1016/bs.apar.2016.08.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Human onchocerciasis (river blindness) is one of the few neglected tropical diseases (NTDs) whose control strategies have been informed by mathematical modelling. With the change in focus from elimination of the disease burden to elimination of Onchocerca volvulus, much remains to be done to refine, calibrate and validate existing models. Under the impetus of the NTD Modelling Consortium, the teams that developed EPIONCHO and ONCHOSIM have joined forces to compare and improve these frameworks to better assist ongoing elimination efforts. We review their current versions and describe how they are being used to address two key questions: (1) where can onchocerciasis be eliminated with current intervention strategies by 2020/2025? and (2) what alternative/complementary strategies could help to accelerate elimination where (1) cannot be achieved? The control and elimination of onchocerciasis from the African continent is at a crucial crossroad. The African Programme for Onchocerciasis Control closed at the end of 2015, and although a new platform for support and integration of NTD control has been launched, the disease will have to compete with a myriad of other national health priorities at a pivotal time in the road to elimination. However, never before had onchocerciasis control a better arsenal of intervention strategies as well as diagnostics. It is, therefore, timely to present two models of different geneses and modelling traditions as they come together to produce robust decision-support tools. We start by describing the structural and parametric assumptions of EPIONCHO and ONCHOSIM; we continue by summarizing the modelling of current treatment strategies with annual (or biannual) mass ivermectin distribution and introduce a number of alternative strategies, including other microfilaricidal therapies (such as moxidectin), macrofilaricidal (anti-wolbachial) treatments, focal vector control and the possibility of an onchocerciasis vaccine. We conclude by discussing challenges, opportunities and future directions.
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Richards F, Rizzo N, Diaz Espinoza CE, Monroy ZM, Crovella Valdez CG, de Cabrera RM, de Leon O, Zea-Flores G, Sauerbrey M, Morales AL, Rios D, Unnasch TR, Hassan HK, Klein R, Eberhard M, Cupp E, Domínguez A. One Hundred Years After Its Discovery in Guatemala by Rodolfo Robles, Onchocerca volvulus Transmission Has Been Eliminated from the Central Endemic Zone. Am J Trop Med Hyg 2015; 93:1295-304. [PMID: 26503275 PMCID: PMC4674249 DOI: 10.4269/ajtmh.15-0364] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 07/17/2015] [Indexed: 11/07/2022] Open
Abstract
We report the elimination of Onchocerca volvulus transmission from the Central Endemic Zone (CEZ) of onchocerciasis in Guatemala, the largest focus of this disease in the Americas and the first to be discovered in this hemisphere by Rodolfo Robles Valverde in 1915. Mass drug administration (MDA) with ivermectin was launched in 1988, with semiannual MDA coverage reaching at least 85% of the eligible population in > 95% of treatment rounds during the 12-year period, 2000-2011. Serial parasitological testing to monitor MDA impact in sentinel villages showed a decrease in microfilaria skin prevalence from 70% to 0%, and polymerase chain reaction (PCR)-based entomological assessments of the principal vector Simulium ochraceum s.l. showed transmission interruption by 2007. These assessments, together with a 2010 serological survey in children 9-69 months of age that showed Ov16 IgG4 antibody prevalence to be < 0.1%, meeting World Health Organization (WHO) guidelines for stopping MDA, and treatment was halted after 2011. After 3 years an entomological assessment showed no evidence of vector infection or recrudescence of transmission. In 2015, 100 years after the discovery of its presence, the Ministry of Health of Guatemala declared onchocerciasis transmission as having been eliminated from the CEZ.
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Affiliation(s)
- Frank Richards
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Nidia Rizzo
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Carlos Enrique Diaz Espinoza
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Zoraida Morales Monroy
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Carol Guillermina Crovella Valdez
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Renata Mendizabal de Cabrera
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Oscar de Leon
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Guillermo Zea-Flores
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Mauricio Sauerbrey
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Alba Lucia Morales
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Dalila Rios
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Thomas R Unnasch
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Hassan K Hassan
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Robert Klein
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Mark Eberhard
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Ed Cupp
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
| | - Alfredo Domínguez
- River Blindness Elimination Program, The Carter Center, Atlanta, Georgia; Centro de Estudios en Salud of the Universidad del Valle de Guatemala (UVG), Guatemala City, Guatemala; Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala; Onchocerciasis Elimination Program for the Americas (OEPA), The Carter Center, Guatemala City, Guatemala; Global Health Infectious Disease Program, Department of Global Health, University of South Florida, Tampa, Florida; Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama
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9
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Kazura JW. More Progress in Eliminating Transmission of Onchocerca volvulus and Wuchereria bancrofti in the Americas: A Portent of Global Eradication. Am J Trop Med Hyg 2015; 93:1128-1129. [PMID: 26503272 PMCID: PMC4674222 DOI: 10.4269/ajtmh.15-0688] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 09/28/2015] [Indexed: 11/07/2022] Open
Affiliation(s)
- James W. Kazura
- *Address correspondence to James W. Kazura, Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Biomedical Research Building 431, 10900 Euclid Avenue, Cleveland, OH 44106-4983. E-mail:
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10
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Mansouri A, Chan V, Njaramba V, Cadotte DW, Albright AL, Bernstein M. Sources of delayed provision of neurosurgical care in a rural kenyan setting. Surg Neurol Int 2015; 6:32. [PMID: 25745587 PMCID: PMC4348798 DOI: 10.4103/2152-7806.152141] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 11/30/2014] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Delay to neurosurgical care can result in significant morbidity and mortality. In this study, we aim to identify and quantify the sources of delay to neurosurgical consultation and care at a rural setting in Kenya. METHODS A mixed-methods, cross-sectional analysis of all patients admitted to the neurosurgical department at Kijabe Hospital (KH) was conducted: A retrospective analysis of admissions from October 1 to December 31, 2013 and a prospective analysis from June 2 to June 20, 2014. Sources of delay were categorized and quantified. The Kruskal-Wallis test was used to identify an overall significant difference among diagnoses. The Mann-Whitney U test was used for pairwise comparisons within groups; the Bonferroni correction was applied to the alpha level of significance (0.05) according to the number of comparisons conducted. IBM SPSS version 22.0 (SPSS, Chicago, IL) was used for statistical analyses. RESULTS A total of 332 admissions were reviewed (237 retrospective, 95 prospective). The majority was pediatric admissions (median age: 3 months). Hydrocephalus (35%) and neural tube defects (NTDs; 27%) were most common. At least one source of delay was identified in 192 cases (58%); 39 (12%) were affected by multiple sources. Delay in primary care (PCPs), in isolation or combined with other sources, comprised 137 of total (71%); misdiagnosis or incorrect management comprised 46 (34%) of these. Finances contributed to delays in 25 of 95 prospective cases. At a median delay of 49 and 200.5 days, the diagnoses of hydrocephalus and tumors were associated with a significantly longer delay compared with NTDs (P < 0.001). CONCLUSION A substantial proportion of patients experienced delays in procuring pediatric neurosurgical care. Improvement in PCP knowledge base, implementation of a triage and referral process, and development of community-based funding strategies can potentially reduce these delays.
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Affiliation(s)
- Alireza Mansouri
- Division of Neurosurgery, Toronto Western Hospital, University Health Network, Hamilton, Canada ; Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Hamilton, Canada ; Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
| | - Vivien Chan
- Division of Neurosurgery, Toronto Western Hospital, University Health Network, Hamilton, Canada
| | | | - David W Cadotte
- Division of Neurosurgery, Toronto Western Hospital, University Health Network, Hamilton, Canada ; Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Hamilton, Canada
| | - A Leland Albright
- Department of Neurosurgery, AIC Kijabe Hospital, Kijabe, Kenya ; University of Wisconsin Health Center, Wisconsin, USA
| | - Mark Bernstein
- Division of Neurosurgery, Toronto Western Hospital, University Health Network, Hamilton, Canada ; Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Hamilton, Canada ; The Greg Wilkins-Barrick Chair in International Surgery, Canada
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11
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Molyneux DH, Hopkins A, Bradley MH, Kelly-Hope LA. Multidimensional complexities of filariasis control in an era of large-scale mass drug administration programmes: a can of worms. Parasit Vectors 2014; 7:363. [PMID: 25128408 PMCID: PMC4261528 DOI: 10.1186/1756-3305-7-363] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 07/30/2014] [Indexed: 12/23/2022] Open
Abstract
The impact of control and elimination programmes by mass drug administration (MDA) targeting onchocerciasis and lymphatic filariasis (LF) in sub-Saharan Africa over the last two decades has resulted in significantly reduced prevalence and intensity of infection, with some areas interrupting transmission. However, given that these infections are often co-endemic and the drugs (either ivermectin alone or combined with albendazole) also impact on soil transmitted helminths (STH), the importance of this, in terms of reaching the global goals has not been assessed. The additional problem posed by Loa loa, where ivermectin cannot be safely administered due to the risk of serious adverse events compounds this situation and has left populations drug naïve and an alternative strategy to eliminate LF is yet to be initiated at scale. Here, we present a series of operational research questions, which must be addressed if the effectiveness of integrated control of filarial and helminth infections is to be understood for the endgame. This is particularly important in the diverse and dynamic epidemiological landscape, which has emerged as a result of the long-term large-scale mass drug administration (or not). There is a need for a more holistic approach to address these questions. Different programmes should examine this increased complexity, given that MDA has multiple impacts, drugs are given over different periods, and programmes have different individual targets.
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Affiliation(s)
- David H Molyneux
- />Centre for Neglected Tropical Diseases, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA UK
| | - Adrian Hopkins
- />Mectizan Donation Program, Task Force for Global Health, Decatur, Atlanta, GA USA
| | - Mark H Bradley
- />GlaxoSmithKline, Global Health Programme, Brentford, UK
| | - Louise A Kelly-Hope
- />Centre for Neglected Tropical Diseases, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA UK
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12
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Keating J, Yukich JO, Mollenkopf S, Tediosi F. Lymphatic filariasis and onchocerciasis prevention, treatment, and control costs across diverse settings: a systematic review. Acta Trop 2014; 135:86-95. [PMID: 24699086 DOI: 10.1016/j.actatropica.2014.03.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 03/21/2014] [Accepted: 03/23/2014] [Indexed: 11/18/2022]
Abstract
The control and eventual elimination of neglected tropical disease (NTD) requires the expansion of interventions such as mass drug administration (MDA), vector control, diagnostic testing, and effective treatment. The purpose of this paper is to present the evidence base for decision-makers on the cost and cost-effectiveness of lymphatic filariasis (LF) and onchocerciasis prevention, treatment, and control. A systematic review of the published literature was conducted. All studies that contained primary or secondary data on costs or cost-effectiveness of prevention and control were considered. A total of 52 papers were included for LF and 24 papers were included for onchocerciasis. Large research gaps exist on the synergies and cost of integrating NTD prevention and control programs, as well as research on the role of health information systems, human resource systems, service delivery, and essential medicines and technology for elimination. The literature available on costs and cost-effectiveness of interventions is also generally older, extremely focal geographically and of limited usefulness for developing estimates of the global economic burden of these diseases and prioritizing among various intervention options. Up to date information on the costs and cost-effectiveness of interventions for LF and onchocerciasis prevention are needed given the vastly expanded funding base for the control and elimination of these diseases.
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Affiliation(s)
- Joseph Keating
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, United States; Department of Global Health Systems and Development, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, United States.
| | - Joshua O Yukich
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, United States; Department of Global Health Systems and Development, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, United States.
| | - Sarah Mollenkopf
- Department of Global Health Systems and Development, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, United States.
| | - Fabrizio Tediosi
- Department of Public Health and Epidemiology, Swiss Tropical and Public Health Institute, Socinstrasse 57, 4001 Basel, Switzerland; University of Basel, Switzerland; Centre for Research on Health and Social Care Management (CERGAS), Università Bocconi, Milan, Italy.
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13
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Cruz-Ortiz N, Gonzalez RJ, Lindblade KA, Richards FO, Sauerbrey M, Zea-Flores G, Dominguez A, Oliva O, Catú E, Rizzo N. Elimination of Onchocerca volvulus Transmission in the Huehuetenango Focus of Guatemala. J Parasitol Res 2012; 2012:638429. [PMID: 22970346 PMCID: PMC3432545 DOI: 10.1155/2012/638429] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Accepted: 07/05/2012] [Indexed: 11/17/2022] Open
Abstract
In Latin America, onchocerciasis is targeted for elimination by 2012 through twice-yearly mass treatment of the eligible population with ivermectin. In Guatemala, two of the four historical endemic foci have demonstrated elimination of transmission, following World Health Organization guidelines. Using established guidelines ophthalmological, serological, and entomological evaluations were conducted in 2007-8 to determine the transmission status of onchocerciasis in the Huehuetenango focus. The prevalence of Onchocerca volvulus microfilariae in the anterior segment of the eye in 365 residents was 0% (95% confidence interval [CI] 0-0.8%), the prevalence of infection of O. volvulus in Simulium ochraceum among 8252 flies collected between November 2007 and April 2008 was 0% (95% CI 0-0.02%), and the prevalence of antibodies to a recombinant O. volvulus antigen in 3118 school age children was 0% (95% CI 0-0.1%). These results showed transmission interruption; thus, in 2009 mass treatment was halted and posttreatment surveillance began. To verify for potential recrudescence an entomological evaluation (from December 2010 to April 2011) was conducted during the 2nd and 3rd year of posttreatment surveillance. A total of 4587 S. ochraceum were collected, and the prevalence of infection of O. volvulus was 0% (95% CI 0-0.04%). Transmission of onchocerciasis in the Huehuetenango focus has been eliminated.
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Affiliation(s)
- Nancy Cruz-Ortiz
- Centro de Estudios en Salud, Universidad del Valle de Guatemala (UVG), 18 avenida 11-95 Zona 15, Vista Hermosa III, Guatemala City, Guatemala
| | - Rodrigo J. Gonzalez
- Centro de Estudios en Salud, Universidad del Valle de Guatemala (UVG), 18 avenida 11-95 Zona 15, Vista Hermosa III, Guatemala City, Guatemala
| | - Kim A. Lindblade
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention (CDC), 1600 Clifton Road NE A-06, Atlanta, GA 30333, USA
- CDC Regional Office for Central America and Panama, UVG, 18 avenida 11-95 Zona 15, Vista Hermosa III, Guatemala City, Guatemala
| | | | - Mauricio Sauerbrey
- Onchocerciasis Elimination Program for the Americas, 14 Calle 3-51 Zona 10, Edificio Murano Center, Oficina 1401, Guatemala City, Guatemala
| | - Guillermo Zea-Flores
- Onchocerciasis Elimination Program for the Americas, 14 Calle 3-51 Zona 10, Edificio Murano Center, Oficina 1401, Guatemala City, Guatemala
| | - Alfredo Dominguez
- Onchocerciasis Elimination Program for the Americas, 14 Calle 3-51 Zona 10, Edificio Murano Center, Oficina 1401, Guatemala City, Guatemala
| | - Orlando Oliva
- Onchocerciasis Elimination Program for the Americas, 14 Calle 3-51 Zona 10, Edificio Murano Center, Oficina 1401, Guatemala City, Guatemala
| | - Eduardo Catú
- Ministerio de Salud Pública y Asistencia Social, 6 avenida 3-45 Zona 11, Guatemala City, Guatemala
| | - Nidia Rizzo
- Centro de Estudios en Salud, Universidad del Valle de Guatemala (UVG), 18 avenida 11-95 Zona 15, Vista Hermosa III, Guatemala City, Guatemala
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14
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Chagas AC, Calvo E, Pimenta PFP, Ribeiro JMC. An insight into the sialome of Simulium guianense (DIPTERA:SIMulIIDAE), the main vector of River Blindness Disease in Brazil. BMC Genomics 2011; 12:612. [PMID: 22182526 PMCID: PMC3285218 DOI: 10.1186/1471-2164-12-612] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 12/19/2011] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Little is known about the composition and function of the saliva in black flies such as Simulium guianense, the main vector of river blindness disease in Brazil. The complex salivary potion of hematophagous arthropods counteracts their host's hemostasis, inflammation, and immunity. RESULTS Transcriptome analysis revealed ubiquitous salivary protein families--such as the Antigen-5, Yellow, Kunitz domain, and serine proteases--in the S. guianense sialotranscriptome. Insect-specific families were also found. About 63.4% of all secreted products revealed protein families found only in Simulium. Additionally, we found a novel peptide similar to kunitoxin with a structure distantly related to serine protease inhibitors. This study revealed a relative increase of transcripts of the SVEP protein family when compared with Simulium vittatum and S. nigrimanum sialotranscriptomes. We were able to extract coding sequences from 164 proteins associated with blood and sugar feeding, the majority of which were confirmed by proteome analysis. CONCLUSIONS Our results contribute to understanding the role of Simulium saliva in transmission of Onchocerca volvulus and evolution of salivary proteins in black flies. It also consists of a platform for mining novel anti-hemostatic compounds, vaccine candidates against filariasis, and immuno-epidemiologic markers of vector exposure.
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Affiliation(s)
- Andrezza C Chagas
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, 12735 Twinbrook Parkway, National Institutes of Health, Rockville, Maryland 20892-8132, USA
- Entomology Laboratory, Centro de Pesquisa René Rachou, Belo Horizonte, Minas Gerais, Brazil
| | - Eric Calvo
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, 12735 Twinbrook Parkway, National Institutes of Health, Rockville, Maryland 20892-8132, USA
| | - Paulo FP Pimenta
- Entomology Laboratory, Centro de Pesquisa René Rachou, Belo Horizonte, Minas Gerais, Brazil
| | - José MC Ribeiro
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, 12735 Twinbrook Parkway, National Institutes of Health, Rockville, Maryland 20892-8132, USA
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15
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Furtado JM, Lansingh VC, Carter MJ, Milanese MF, Peña BN, Ghersi HA, Bote PL, Nano ME, Silva JC. Causes of blindness and visual impairment in Latin America. Surv Ophthalmol 2011; 57:149-77. [PMID: 22137039 DOI: 10.1016/j.survophthal.2011.07.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 07/12/2011] [Accepted: 07/19/2011] [Indexed: 11/26/2022]
Abstract
We review what is known in each country of the Latin American region with regards to blindness and visual impairment and make some comparisons to Hispanic populations in the United States. Prevalence of blindness varied from 1.1% in Argentina to 4.1% in Guatemala in people 50 years of age and older, with the major cause being cataract. Diabetic retinopathy and glaucoma are starting to make serious inroads, although epidemiological data are limited, and age-related macular degeneration is now a concern in some populations. Infectious diseases such as trachoma and onchocerciasis are quickly diminishing. Although progress has been made, retinopathy of prematurity remains the major cause of childhood blindness. If VISION 2020 is to succeed, many more epidemiological studies will be needed to set priorities, although some can be of the Rapid Assessment of Avoidable Blindness design. Developing the infrastructure for screening and treatment of ophthalmic disease in Latin America continues to be a challenge.
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Affiliation(s)
- João M Furtado
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
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16
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Gustavsen K, Hopkins A, Sauerbrey M. Onchocerciasis in the Americas: from arrival to (near) elimination. Parasit Vectors 2011; 4:205. [PMID: 22024050 PMCID: PMC3214172 DOI: 10.1186/1756-3305-4-205] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 10/25/2011] [Indexed: 11/10/2022] Open
Abstract
Onchocerciasis (river blindness) is a blinding parasitic disease that threatens the health of approximately 120 million people worldwide. While 99% of the population at-risk for infection from onchocerciasis live in Africa, some 500,000 people in the Americas are also threatened by infection. A relatively recent arrival to the western hemisphere, onchocerciasis was brought to the New World through the slave trade and spread through migration. The centuries since its arrival have seen advances in diagnosing, mapping and treating the disease. Once endemic to six countries in the Americas (Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela), onchocerciasis is on track for interruption of transmission in the Americas by 2012, in line with Pan American Health Organization resolution CD48.R12. The success of this public health program is due to a robust public-private partnership involving national governments, local communities, donor organizations, intergovernmental bodies, academic institutions, non-profit organizations and the pharmaceutical industry. The lessons learned through the efforts in the Americas are in turn informing the program to control and eliminate onchocerciasis in Africa. However, continued support and investment are needed for program implementation and post-treatment surveillance to protect the gains to-date and ensure complete elimination is achieved and treatment can be safely stopped within all 13 regional foci.
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Affiliation(s)
- Ken Gustavsen
- Corporate Responsibility, Merck, 1 Merck Drive, WS2A-56, Whitehouse Station, New Jersey 08889, USA.
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17
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Cupp E, Sauerbrey M, Richards F. Elimination of human onchocerciasis: history of progress and current feasibility using ivermectin (Mectizan(®)) monotherapy. Acta Trop 2011; 120 Suppl 1:S100-8. [PMID: 20801094 DOI: 10.1016/j.actatropica.2010.08.009] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 08/05/2010] [Accepted: 08/11/2010] [Indexed: 11/24/2022]
Abstract
We review and analyze approaches over a 65 year period that have proven successful for onchocerciasis control in several different epidemiological settings. These include vector control with the goal of transmission interruption versus the use of mass drug administration using ivermectin (Mectizan(®)) monotherapy. Ivermectin has proven exceedingly effective because it is highly efficacious against Onchocerca volvulus microfilariae, the etiological agent of onchocercal skin and ocular disease and the infective stage for the vector. For these reasons, the drug was donated by the Merck Company for regional control programs in Africa and the Americas. Recurrent treatment with ivermectin at semi-annual intervals also impacts adult worms and result in loss of fecundity and increased mortality. Using a strategy of 6-monthly treatments with high coverage rates, the Onchocerciasis Elimination Program for the Americas has interrupted transmission in seven of the thirteen foci in the Americas and is on track to eliminate onchocerciasis in the region by 2015. Treatments given annually or semi-annually for 15-17 years in three hyperendemic onchocerciasis foci in Mali and Senegal also have resulted in a few infections in the human population with transmission levels below thresholds postulated for elimination. Follow-up evaluations did not detect any recrudescence of infection or transmission, suggesting that onchocerciasis elimination could be feasible with Mectizan(®) treatment in some endemic foci in Africa.
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Schneider MC, Aguilera XP, Barbosa da Silva Junior J, Ault SK, Najera P, Martinez J, Requejo R, Nicholls RS, Yadon Z, Silva JC, Leanes LF, Periago MR. Elimination of neglected diseases in latin america and the Caribbean: a mapping of selected diseases. PLoS Negl Trop Dis 2011; 5:e964. [PMID: 21358810 PMCID: PMC3039687 DOI: 10.1371/journal.pntd.0000964] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 01/12/2011] [Indexed: 11/17/2022] Open
Abstract
In Latin America and the Caribbean, around 195 million people live in poverty, a situation that increases the burden of some infectious diseases. Neglected diseases, in particular, are often restricted to poor, marginalized sections of the population. Tools exist to combat these diseases, making it imperative to work towards their elimination. In 2009, the Pan American Health Organization (PAHO) received a mandate to support the countries in the Region in eliminating neglected diseases and other poverty-related infections. The objective of this study is to analyze the presence of selected diseases using geo-processing techniques. Five diseases with information available at the first sub-national level (states) were mapped, showing the presence of the disease ("hotspots") and overlap of diseases ("major hotspots"). In the 45 countries/territories (approximately 570 states) of the Region, there is: lymphatic filariasis in four countries (29 states), onchocerciasis in six countries (25 states), schistosomiasis in four countries (39 states), trachoma in three countries (29 states), and human rabies transmitted by dogs in ten countries (20 states). Of the 108 states with one or more of the selected diseases, 36 states present the diseases in overlapping areas ("major hotspots"). Additional information about soil-transmitted helminths was included. The analysis suggests a majority of the selected diseases are not widespread and can be considered part of an unfinished agenda with elimination as a goal. Integrated plans and a comprehensive approach, ensuring access to existing diagnostic and treatment methods, and establishing a multi-sectoral agenda that addresses social determinants, including access to adequate water and sanitation, are required. Future studies can include additional diseases, socio-economic and environmental variables.
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19
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Liese B, Rosenberg M, Schratz A. Programmes, partnerships, and governance for elimination and control of neglected tropical diseases. Lancet 2010; 375:67-76. [PMID: 20109865 DOI: 10.1016/s0140-6736(09)61749-9] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neglected tropical diseases represent one of the most serious burdens to public health. Many can be treated cost-effectively, yet they have been largely ignored on the global health policy agenda until recently. In this first paper in the Series we review the fragmented structure of elimination and control programmes for these diseases, starting with the ambiguous definition of a neglected tropical disease. We describe selected international control initiatives and present their effect, governance arrangements, and financing mechanisms, including substantial drug-donation programmes. We also discuss efforts to exploit shared features of these diseases by integration of selected control activities within countries, thus creating economies of scope. Finally we address the challenges, resulting from the diversity of disease control approaches and governance structures-both nationally and internationally-and provide some suggestions for the way forward.
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Affiliation(s)
- Bernhard Liese
- Department of International Health, Georgetown University, Washington, DC 20007, USA.
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Gonzalez RJ, Cruz-Ortiz N, Rizzo N, Richards J, Zea-Flores G, Domínguez A, Sauerbrey M, Catú E, Oliva O, Richards FO, Lindblade KA. Successful interruption of transmission of Onchocerca volvulus in the Escuintla-Guatemala focus, Guatemala. PLoS Negl Trop Dis 2009; 3:e404. [PMID: 19333366 PMCID: PMC2656640 DOI: 10.1371/journal.pntd.0000404] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Accepted: 03/04/2009] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Elimination of onchocerciasis (river blindness) through mass administration of ivermectin in the six countries in Latin America where it is endemic is considered feasible due to the relatively small size and geographic isolation of endemic foci. We evaluated whether transmission of onchocerciasis has been interrupted in the endemic focus of Escuintla-Guatemala in Guatemala, based on World Health Organization criteria for the certification of elimination of onchocerciasis. METHODOLOGY/PRINCIPAL FINDINGS We conducted evaluations of ocular morbidity and past exposure to Onchocerca volvulus in the human population, while potential vectors (Simulium ochraceum) were captured and tested for O. volvulus DNA; all of the evaluations were carried out in potentially endemic communities (PEC; those with a history of actual or suspected transmission or those currently under semiannual mass treatment with ivermectin) within the focus. The prevalence of microfilariae in the anterior segment of the eye in 329 individuals (> or =7 years old, resident in the PEC for at least 5 years) was 0% (one-sided 95% confidence interval [CI] 0-0.9%). The prevalence of antibodies to a recombinant O. volvulus antigen (Ov-16) in 6,432 school children (aged 6 to 12 years old) was 0% (one-sided 95% IC 0-0.05%). Out of a total of 14,099 S. ochraceum tested for O. volvulus DNA, none was positive (95% CI 0-0.01%). The seasonal transmission potential was, therefore, 0 infective stage larvae per person per season. CONCLUSIONS/SIGNIFICANCE Based on these evaluations, transmission of onchocerciasis in the Escuintla-Guatemala focus has been successfully interrupted. Although this is the second onchocerciasis focus in Latin America to have demonstrated interruption of transmission, it is the first focus with a well-documented history of intense transmission to have eliminated O. volvulus.
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Affiliation(s)
- Rodrigo J. Gonzalez
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Nancy Cruz-Ortiz
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Nidia Rizzo
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Jane Richards
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Guillermo Zea-Flores
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala
| | - Alfredo Domínguez
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala
| | - Mauricio Sauerbrey
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala
| | - Eduardo Catú
- Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala
| | - Orlando Oliva
- Onchocerciasis Elimination Program for the Americas (OEPA), Guatemala City, Guatemala
| | | | - Kim A. Lindblade
- Division of Parasitic Diseases, National Center for Zoonotic, Vector-Borne and Enteric Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail:
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Sauerbrey M. The Onchocerciasis Elimination Program for the Americas (OEPA). ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2008; 102 Suppl 1:25-9. [PMID: 18718151 DOI: 10.1179/136485908x337454] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Human onchocerciasis (river blindness) occurs in 13 foci distributed among six countries in Latin America (Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela), where about 500,000 people are considered at risk. An effort to eliminate the disease from the region was launched in response to a specific resolution adopted by the PanAmerican Health Organization (PAHO) in 1991: to eliminate onchocerciasis from the region, as a public-health problem, by 2007. The effort took advantage of the donation of the drug Mectizan (ivermectin) by Merck & Co., Inc. In 1992, the Onchocerciasis Elimination Program for the Americas (OEPA) was launched, with its headquarters in Guatemala, to act as a technical and co-ordinating body of a multinational, multi-agency coalition that includes the endemic countries, PAHO, The Carter Center, Lions Clubs, the United States Centers for Disease Control and Prevention, The Bill and Melinda Gates Foundation, Merck & Co., Inc., and other partners. This public-private partnership facilitated the establishment of programmes for the semi-annual mass administration of Mectizan in the six countries with onchocerciasis. The aims were to (1) provide sustained treatments, with coverage reaching at least 85% of those eligible to receive the drug (in the 1845 endemic communities that are distributed within the 13 regional foci); (2) eliminate new morbidity caused by Onchocerca volvulus infection by 2007; and (3) eliminate transmission of the parasite wherever feasible. Significant progress has already been made in all six countries, each of which has active programmes with treatment coverages exceeding the target of 85%. The progress is being documented in accordance with certification guidelines for onchocerciasis elimination established by the World Health Organization. No new cases of onchocercal blindness are being reported in the region, and ocular disease attributable to O. volvulus has been eliminated from nine of the 13 foci. Treatment is no longer needed in Santa Rosa, Guatemala, where transmission has been eliminated, and will be halted in at least three other foci in 2008, as they confirm the interruption of transmission. Treatment efforts should now be concentrated on the five foci where significant transmission remains: Central (Guatemala), Amazonas/Roraima (Brazil), North-central (Venezuela), North-east (Venezuela) and South (Venezuela). Based upon the experience gained, the well-established operations and the success achieved so far, it seems reasonable to estimate that onchocerciasis could be eliminated from most of the remaining foci in the Americas by 2012. The protocol, criteria and deadline for stopping all onchocerciasis treatment in the region should soon be addressed by OEPA's Program Co-ordinating Committee (PCC), in co-ordination with the PAHO.
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Affiliation(s)
- M Sauerbrey
- Onchocerciasis Elimination Program for the Americas (OEPA), 14 Calle 3-51 Zona 10, Edificio Murano Center, Oficina 1401, Guatemala City, Guatemala.
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Kalluri S, Gilruth P, Rogers D, Szczur M. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review. PLoS Pathog 2008; 3:1361-71. [PMID: 17967056 PMCID: PMC2042005 DOI: 10.1371/journal.ppat.0030116] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed.
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Vieira JC, Cooper PJ, Lovato R, Mancero T, Rivera J, Proaño R, López AA, Guderian RH, Guzmán JR. Impact of long-term treatment of onchocerciasis with ivermectin in Ecuador: potential for elimination of infection. BMC Med 2007; 5:9. [PMID: 17521449 PMCID: PMC1890547 DOI: 10.1186/1741-7015-5-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Accepted: 05/23/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Onchocerciasis is a leading cause of blindness worldwide, hence elimination of the infection is an important health priority. Community-based treatment programs with ivermectin form the basis of control programs for the disease in Latin America. The long-term administration of ivermectin could eliminate Onchocerca volvulus infection from endemic areas in Latin America. METHODS A strategy of annual to twice-annual treatments with ivermectin has been used for onchocerciasis in endemic communities in Ecuador for up to 14 years. The impact of ivermectin treatment on ocular morbidity, and O. volvulus infection and transmission was monitored in seven sentinel communities. RESULTS Over the period 1990-2003, high rates of treatment coverage of the eligible population were maintained in endemic communities (mean 85.2% per treatment round). Ivermectin reduced the prevalence of anterior segment disease of the eye to 0% in sentinel communities and had a major impact on the prevalence and transmission of infection, with possible elimination of infection in some foci. CONCLUSION The distribution of ivermectin in endemic communities in Ecuador might have eliminated ocular morbidity and significant progress has been made towards elimination of the infection. A strategy of more frequent treatments with ivermectin may be required in communities where the infection persists to achieve the objective of elimination of the infection from Ecuador. The elimination of the infection from an endemic country in Latin America would be a major public health achievement and could stimulate the implementation of elimination strategies in other endemic countries.
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Affiliation(s)
- Juan Carlos Vieira
- Programa Nacional de Eliminación de la Oncocercosis en el Ecuador, Servicio Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Ministry of Public Health, Guayaquil, Ecuador
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | - Philip J Cooper
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | - Raquel Lovato
- Programa Nacional de Eliminación de la Oncocercosis en el Ecuador, Servicio Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Ministry of Public Health, Guayaquil, Ecuador
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | | | - Jorge Rivera
- Programa Nacional de Eliminación de la Oncocercosis en el Ecuador, Servicio Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Ministry of Public Health, Guayaquil, Ecuador
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | - Roberto Proaño
- Programa Nacional de Eliminación de la Oncocercosis en el Ecuador, Servicio Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Ministry of Public Health, Guayaquil, Ecuador
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | - Andrea A López
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | - Ronald H Guderian
- Desarrollo Comunitario Vozandes HCJB, Casilla 17-17-691, Quito, Ecuador
| | - José Rumbea Guzmán
- Programa Nacional de Eliminación de la Oncocercosis en el Ecuador, Servicio Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Ministry of Public Health, Guayaquil, Ecuador
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Marchon-Silva V, Caër JC, Post RJ, Maia-Herzog M, Fernandes O. Detection of Onchocerca volvulus (Nematoda: Onchocercidae) infection in vectors from Amazonian Brazil following mass Mectizan™ distribution. Mem Inst Oswaldo Cruz 2007; 102:197-202. [PMID: 17426885 DOI: 10.1590/s0074-02762007005000010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Accepted: 02/06/2007] [Indexed: 05/14/2023] Open
Abstract
Detection of Onchocerca volvulus in Simulium populations is of primary importance in the assessment of the effectiveness of onchocerciasis control programs. In Brazil, the main focus of onchocerciasis is in the Amazon region, in a Yanomami reserve. The main onchocerciasis control strategy in Brazil is the semi-annually mass distribution of the microfilaricide ivermectin. In accordance with the control strategy for the disease, polymerase chain reaction (PCR) was applied in pools of simuliids from the area to detect the helminth infection in the vectors, as recommended by the Onchocerciasis Elimination Program for the Americas and the World Health Organization. Systematic sampling was performed monthly from September 1998 to October 1999, and a total of 4942 blackflies were collected from two sites (2576 from Balawaú and 2366 from Toototobi). The molecular methodology was found to be highly sensitive and specific for the detection of infected and/or infective blackflies in pools of 50 blackflies. The results from the material collected under field conditions showed that after the sixth cycle of distribution of ivermectin, the prevalence of infected blackflies with O. volvulus had decreased from 8.6 to 0.3% in Balawaú and from 4 to 0.1% in Toototobi.
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Affiliation(s)
- Verônica Marchon-Silva
- Laboratório de Epidemiologia Molecular de Doenças Infecciosas, Departamento de Medicina Tropical, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brasil.
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Alleman MM, Twum-Danso NAY, Thylefors BI. The Mectizan Donation Program - highlights from 2005. FILARIA JOURNAL 2006; 5:11. [PMID: 17005039 PMCID: PMC1618829 DOI: 10.1186/1475-2883-5-11] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Accepted: 09/27/2006] [Indexed: 12/03/2022]
Abstract
Through the Mectizan® Donation Program, Merck & Co., Inc. has donated Mectizan (ivermectin, MSD) for the treatment of onchocerciasis worldwide since 1987. Mectizan has also been donated for the elimination of lymphatic filariasis (LF) since 1998 in African countries and in Yemen where onchocerciasis and LF are co-endemic; for LF elimination programs, Mectizan is co-administered with albendazole, which is donated by GlaxoSmithKline. The Mectizan Donation Program works in collaboration with the Mectizan Expert Committee/Albendazole Coordination, its scientific advisory committee. In 2005, a total of 62,201,310 treatments of Mectizan for onchocerciasis were approved for delivery via mass treatment programs in Africa, Latin America, and Yemen. Seventy-seven percent and 20% of these treatments for onchocerciasis were for countries included in the African Programme for Onchocerciasis Control (APOC) and the former-Onchocerciasis Control Programme in West Africa (OCP), respectively. The remaining 3% of treatments approved were for the six onchocerciasis endemic countries in Latin America, where mass treatment is carried out twice-yearly with the goal of completely eliminating morbidity and eventually transmission of infection, and for Yemen. All 33 onchocerciasis endemic countries where mass treatment with Mectizan is indicated have ongoing mass treatment programs. In 2005, 42,052,583 treatments of co-administered albendazole and Mectizan were approved for national Programs to Eliminate LF (PELFs) in Africa and Yemen. There are ongoing PELFs using albendazole and Mectizan in nine African countries and Yemen; these represent 35% of the total number of countries expected to require the co-administration of these two chemotherapeutic agents for LF elimination. In Africa, the expansion of existing PELFs and the initiation of new ones have been hampered by lack of resources, technical difficulties with the mapping of LF endemicity, and the co-endemicity of LF and loiasis. Included in this review are recommendations recently put forward for the co-administration of albendazole and Mectizan in areas endemic for LF, loiasis, and onchocerciasis.
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Affiliation(s)
- Mary M Alleman
- The MectizanDonation Program, 750 Commerce Drive, Suite 400, Decatur, GA 30030, USA
| | - Nana AY Twum-Danso
- The MectizanDonation Program, 750 Commerce Drive, Suite 400, Decatur, GA 30030, USA
| | - Björn I Thylefors
- The MectizanDonation Program, 750 Commerce Drive, Suite 400, Decatur, GA 30030, USA
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Abstract
Onchocerciasis is a filarial infection which causes blindness and debilitating skin lesions. The disease occurs in 37 countries, of which 30 are found in Africa (the most affected in terms of the distribution and the severity of the clinical manifestations of the disease), six in the Americas and one in the Arabian Peninsula. The latest WHO Expert Committee on Onchocerciasis estimated that in 1995 around 17.7 million persons were infected, about 270,000 of whom were blind and another 500,000 severely visually impaired. The disease is responsible for 1 million DALYs. Eye disease from onchocerciasis accounts for 40% of DALYs annually although severe skin disease is also recognized as of public health significance. Great progress has been made in the last thirty years in the control of onchocerciasis, both in Africa and the Americas, and this progress has been due largely to international public-private partnerships, sustained funding regional programmes, and new tools and technology. Landmarks in the global control of river blindness include the significant success of the Onchocerciasis Control Programme of West Africa (1975-2002), and the donation of ivermectin (Mectizan) by Merck & Co. Inc., in 1988, a medicine that is distributed to millions free of charge each year. Future major technical challenges of onchocerciasis control include ivermectin mass administration in areas co-endemic for the parasite Loa loa in the light of possible severe adverse reactions, ivermectin treatment in hypoendemic areas hitherto excluded from African control programmes, sustainability of ivermectin distribution, post-control surveillance for recrudescence detection, surveillance for emergence of resistance, and decisions of when to stop mass ivermectin treatments. There is the need to develop the appropriate information systems and diagnostic tools to help in accomplishing many of these tasks. A search for a second-line treatment or as an additional drug to ivermectin as well as a search for a macrofilaricide are issues that need to be addressed in the future.
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Affiliation(s)
- Boakye A Boatin
- TDR, World Health Organization, CH-1211 Geneva 27, Switzerland
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Gómez-Priego A, Mendoza R, de-la-Rosa JL. Prevalence of antibodies to onchocerca volvulus in residents of Oaxaca, Mexico, treated for 10 years with ivermectin. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2005; 12:40-3. [PMID: 15642982 PMCID: PMC540190 DOI: 10.1128/cdli.12.1.40-43.2005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Studies to determine the prevalence of antibodies to Onchocerca volvulus, prior to and after actions carried out to interrupt transmission, are scarce in Mexico. Here we report the prevalence of immunoglobulin G (IgG) and IgG4 antibodies in an enzyme-linked immunosorbent assay (ELISA) against a crude extract of O. volvulus adult worm in serum samples from persons under noninterrupted biannual treatment with ivermectin in areas of onchocercosis endemicity in Mexico. To perform the prevalence studies, the ELISA procedures were first evaluated. Serological studies were performed with serum samples from skin microfilaria carriers from Guatemala and from people microfilariodermic negative living in the same area as the Guatemalan patients. Sensitivity values for IgG or IgG4 detection were 71 and 86%, while specificities were 92 and 100%, respectively. No anti-O. volvulus antibodies were found in samples from nonendemic controls from Mexico, but 3 of 71 samples from residents in the onchocercosis area of Oaxaca, Mexico, and who have been under ivermectin treatment during the last 10 years were only positive to IgG. Notwithstanding that the IgG4 isotype was not detected and a low (4.2%) anti-O. volvulus IgG antibody prevalence was found, a seroepidemiological follow-up must be performed in order to confirm interruption of onchocercosis transmission in the area of Oaxaca, Mexico, in which onchocercosis is endemic.
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Affiliation(s)
- Alberto Gómez-Priego
- Laboratorio de Helmintos Tisulares, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Carpio 470, Santo Tomás, Miguel Hidalgo, México D.F. 11340.
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Vieira JC, Brackenboro L, Porter CH, Basáñez MG, Collins RC. Spatial and temporal variation in biting rates and parasite transmission potentials of onchocerciasis vectors in Ecuador. Trans R Soc Trop Med Hyg 2005; 99:178-95. [PMID: 15653120 DOI: 10.1016/j.trstmh.2004.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2004] [Revised: 03/01/2004] [Accepted: 03/03/2004] [Indexed: 11/16/2022] Open
Abstract
The influence of spatial and temporal factors on onchocerciasis transmission by Simulium exiguum s.l. and S. quadrivittatum in Ecuador was investigated to help develop sampling protocols for entomological surveillance of ivermectin programmes. Flies were collected in alternate months (November 1995-November 1996) at four sites each in the hyperendemic communities of San Miguel and El Tigre. A fixed-effects analysis of variance was used to explore the influence on vector abundance of locality, site, month and hour. Infectivity rates detected by dissection and PCR assays were compared. Simulium exiguum s.l. predominated at El Tigre (75%) whereas S. quadrivittatum prevailed at San Miguel (62%). Vector abundance was highest on river banks and outside houses. Biting and infection rates peaked from March to July. Hourly activity patterns were bimodal in S. exiguum but unimodal in S. quadrivittatum. Annual transmission potentials (ATP) for both species combined were 385 and 733 third stage larvae/person in San Miguel and El Tigre respectively, with S. exiguum accounting for 80% of the combined ATP at both localities. We recommend protocols that may maximize detection of parasite transmission. Infection rates thus obtained must be linked with vector density estimates to assess meaningfully host exposure as treatment progresses.
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Affiliation(s)
- J C Vieira
- Programa de Control de Oncocercosis en Ecuador, Ministerio de Salud Pública de Ecuador, Calle Villalengua # 267 y 10 de Agosto, HCJB Casilla 17-17-691, Hospital Vozandes, Quito, Ecuador
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Nishtar S. Public - private 'partnerships' in health - a global call to action. Health Res Policy Syst 2004; 2:5. [PMID: 15282025 PMCID: PMC514532 DOI: 10.1186/1478-4505-2-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Accepted: 07/28/2004] [Indexed: 11/28/2022] Open
Abstract
The need for public-private partnerships arose against the backdrop of inadequacies on the part of the public sector to provide public good on their own, in an efficient and effective manner, owing to lack of resources and management issues. These considerations led to the evolution of a range of interface arrangements that brought together organizations with the mandate to offer public good on one hand, and those that could facilitate this goal though the provision of resources, technical expertise or outreach, on the other. The former category includes of governments and intergovernmental agencies and the latter, the non-profit and for-profit private sector. Though such partnerships create a powerful mechanism for addressing difficult problems by leveraging on the strengths of different partners, they also package complex ethical and process-related challenges. The complex transnational nature of some of these partnership arrangements necessitates that they be guided by a set of global principles and norms. Participation of international agencies warrants that they be set within a comprehensive policy and operational framework within the organizational mandate and involvement of countries requires legislative authorization, within the framework of which, procedural and process related guidelines need to be developed. This paper outlines key ethical and procedural issues inherent to different types of public-private arrangements and issues a Global Call to Action.
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Abstract
Over a comparatively short period of time, the development and distribution of ivermectin (Mectizan) has radically altered the consequences of infection with Onchocerca volvulus. To achieve this required the fostering of many partnerships and the development of new tools and methods. The long-term commitment of Merck, the World Bank and other sponsors, as well as governments and non-governmental organizations, has been crucial. Yet the enthusiasm with which communities have taken up the delivery of ivermectin among themselves is perhaps the greatest reason for the success of this programme. The present challenge is sustaining the methods that have brought success so far, and making them part of health services and disease control programmes in some of the world's most impoverished and unstable areas. A major part of this challenge is continuing the commitment to controlling onchocerciasis as memory of the disease is fading, and while the hope of elimination or eradication for most endemic countries remains distant.
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Affiliation(s)
- G Burnham
- The Johns Hopkins Bloomberg School of Public Health, Department of International Health, Baltimore, MD 21205, USA.
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Abstract
The Mectizan Donation Program (MDP) has been perceived as a highly effective public health programme, and as a possible model for addressing future problems in international health. This evaluation examines how the MDP partnership has been functioning from the perspectives of partner organizations. The results of a survey of 25 partners show that the perceived benefits far outweigh the problems, and that the direct costs to the organizations have been minimal. The partnership is rated highly on many aspects of governance and management, with relatively few problems identified. A factor analysis demonstrated that a wide range of factors have influenced the partners' perceptions. The benefits with the largest weights appear to be those related to external perceptions of the organization, and those indicating that the organization feels that its opinions will matter and lead to action in the partnership. The biggest factors influencing the positive perceptions on the governance and management of the MDP partnership appear to be the involvement of senior leaders from different organizations, and being able to agree on priorities. The MDP has been able to involve a large and heterogeneous number of partner organizations through relatively informal mechanisms that rely on goodwill and reciprocity. The survey results show how there was a strong alignment of the MDP with the interests of the various partners, and that a manageable number of problems were addressed and services provided. While having long-term goals, the MDP and the onchocerciasis control programmes have been effective at demonstrating the effectiveness of the approach through regular, professional, and outcome-oriented evaluations. Although the MDP is considered to be central to concerns of national officials, this feature is not rated as high as public perceptions, the internal characteristics of the partnership, or its accomplishments. Similarly, the need to secure resources is not viewed as a major determinant of the partnership's success, perhaps because resources were readily available through Merck and the partner organizations and programmes. These findings, along with the strategic and operational success of the MDP confirm the view that this type of public-private partnership should be pursued vigorously in other areas of public health. Other potential partnerships would do well to examine the characteristics of the MDP partnership, with careful attention to the features of its governance and the management, including a strong alignment of interests with partners, balancing a long-term vision with clarity of roles and intensive management of coordination, and professional and results-oriented accountability.
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Affiliation(s)
- David H Peters
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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Moussala M, Fobi G, Ongolo Zogo P, Bella Hiag LA, Bengono G, McMoli TE. Survenue d’hémorragies rétiniennes lors du traitement de l’onchocercose par l’ivermectine chez une patiente co-infectée par la loase. J Fr Ophtalmol 2004; 27:63-6. [PMID: 14968080 DOI: 10.1016/s0181-5512(04)96094-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A case of retinal hemorrhages with special features and degradation of the general condition is reported in a 27-year-old female patient, following the ingestion of ivermectin for the treatment of onchocerciasis. The patient was infested by both Onchocerca volvulus and Loa loa. A bilateral peripheral temporal location of the retinal lesions was observed. The role of L. loa microfilarial load in the occurrence of the retinal lesions as well as the transient character of the lesions are discussed, based on the clinical observation and with reference to the literature. The authors call for setting up a rapid therapeutic system to take care of serious adverse reactions following treatment with ivermectin in areas with a high prevalence of L. loa infestation.
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Affiliation(s)
- M Moussala
- Service d'Ophtalmologie, Hôpital central, Yaoundé, Cameroun
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Soumbey-Alley E, Basáñez MG, Bissan Y, Boatin BA, Remme JHF, Nagelkerke NJD, de Vlas SJ, Borsboom GJJM, Habbema JDF. Uptake of Onchocerca volvulus (Nematoda: Onchocercidae) by Simulium (Diptera: Simuliidae) is not strongly dependent on the density of skin microfilariae in the human host. JOURNAL OF MEDICAL ENTOMOLOGY 2004; 41:83-94. [PMID: 14989351 DOI: 10.1603/0022-2585-41.1.83] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The relation between the number of microfilariae (mf) ingested by host-seeking vectors of human onchocerciasis and skin mf load is an important component of the population biology of Onchocerca volvulus, with implications for disease control and evaluation of the risk of transmission recrudescence. The microsimulation model ONCHOSIM has been used to assess such risk in the area of the Onchocerciasis Control Program (OCP) in West Africa, based on a strongly nonlinear relation between vector mf uptake and human mf skin density previously published. However, observed levels of recrudescence have exceeded predictions, warranting a recalibration of the model. To this end, we present the results of a series of fly-feeding experiments carried out in savanna and forest localities of West Africa. Flies belonging to Simulium damnosum s.s., S. sirbanum, S. soubrense, and S. leonense were fed on mf carriers and dissected to assess the number of ingested mf escaping imprisonment by the peritrophic matrix (the number of exo-peritrophic mf), a predictor of infective larval output. The method of instrumental variables was used to obtain (nearly) unbiased estimates of the parameters of interest, taking into account error in the measurement of skin mf density. This error is often neglected in these types of studies, making it difficult to ascertain the degree of density-dependence truly present in the relation between mf uptake and skin load. We conclude that this relation is weakly (yet significantly) nonlinear in savanna settings but indistinguishable from linearity in forest vectors. Exo-peritrophic mf uptake does not account for most of the density dependence in the transmission dynamics of the parasite as previously thought. The number of exo-mf in forest simuliids is at least five times higher than in the savanna vectors. Parasite abundance in human onchocerciasis is regulated by poorly known mechanisms operating mainly on other stages of the lifecycle.
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Affiliation(s)
- Edoh Soumbey-Alley
- World Health Organization, Onchocerciasis Control Program, B.P. 549, Ouagadougou, Burkina Faso, West Africa
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Drameh PS, Richards FO, Cross C, Etya'alé DE, Kassalow JS. Ten years of NGDO action against river blindness. Trends Parasitol 2002; 18:378-80. [PMID: 12377246 DOI: 10.1016/s1471-4922(02)02362-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
For a decade, a dozen non-governmental development organizations (NGDOs) have organized themselves into a Geneva-based coordination group with the goal of global control of onchocerciasis through mass distribution of ivermectin (Mectizan(R)). Members of this group have worked with Ministries of Health and other partners to empower communities affected by the disease to take responsibility for their own treatment. The NGDO Group has played a key role in the governance of international onchocerciasis control effort, particularly as a partner within the African Programme for Onchocerciasis Control. Ten years on, it is now time to take stock of activities, review the lessons learned and confront future challenges.
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Affiliation(s)
- Pamela S Drameh
- Prevention of Blindness and Deafness (PBD), World Health Organization, 20 Avenue Appia, 1211 27 Geneva 27, Switzerland.
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Abstract
In the last decade, health indicators in Latin America and the Caribbean reflect advances. The per capita public expenditure on health care has increased in many countries. Despite these improvements, it is estimated that for every million population in Latin America and the Caribbean, 5,000 are blind and 20,000 are visually impaired; at least 66% of the blindness is attributable to treatable conditions such as cataract. The cataract surgery rate in the region remains low as compared to the industrialized countries, although it is higher than many other regions of the world. The availability of eye care services varies from country to country within the region, and the number of ophthalmologists per million population in the richest countries may be nine times more than in the poorest. Access, defined as the distance between the consumer and the services, is problematic in countries with isolated areas in the rainforest or high mountains, poor road systems, or lack of public transportation. Affordability is an important issue that limits utilization of services by the poorest segments of the population in nearly all countries in Latin America and the Caribbean.
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Affiliation(s)
- Juan Carlos Silva
- Johns Hopkins School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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Clasen TF. The public-private partnership for the Central American handwashing initiative: reflections from a private sector perspective. Trop Med Int Health 2002; 7:197-200. [PMID: 11903981 DOI: 10.1046/j.1365-3156.2002.00860.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Richards FO, Boatin B, Sauerbrey M, Sékétéli A. Control of onchocerciasis today: status and challenges. Trends Parasitol 2001; 17:558-63. [PMID: 11756018 DOI: 10.1016/s1471-4922(01)02112-2] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Alley WS, van Oortmarssen GJ, Boatin BA, Nagelkerke NJD, Plaisier AP, Remme JHF, Lazdins J, Borsboom GJJM, Habbema JDF. Macrofilaricides and onchocerciasis control, mathematical modelling of the prospects for elimination. BMC Public Health 2001; 1:12. [PMID: 11734070 PMCID: PMC60995 DOI: 10.1186/1471-2458-1-12] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2001] [Accepted: 11/06/2001] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In most endemic parts of the world, onchocerciasis (river blindness) control relies, or will soon rely, exclusively on mass treatment with the microfilaricide ivermectin. Worldwide eradication of the parasite by means of this drug is unlikely. Macrofilaricidal drugs are currently being developed for human use. METHODS We used ONCHOSIM, a microsimulation mathematical model of the dynamics of onchocerciasis transmission, to explore the potentials of a hypothetical macrofilaricidal drug for the elimination of onchocerciasis under different epidemiological conditions, as characterized by previous intervention strategies, vectorial capacity and levels of coverage. RESULTS With a high vector biting rate and poor coverage, a very effective macrofilaricide would appear to have a substantially higher potential for achieving elimination of the parasite than does ivermectin. CONCLUSIONS Macrofilaricides have a substantially higher potential for achieving onchocerciasis elimination than ivermectin, but high coverage levels are still key. When these drugs become available, onchocerciasis elimination strategies should be reconsidered. In view of the impact of control efforts preceding the introduction of macrofilaricides on the success of elimination, it is important to sustain current control efforts.
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Affiliation(s)
- William Soumbey Alley
- Onchocerciasis Control Programme, World Health Organization, B.P. 549, Ouagadougou, Burkina Faso
| | - Gerrit J van Oortmarssen
- Department of Public Health, Erasmus University, Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
| | - Boakye A Boatin
- Onchocerciasis Control Programme, World Health Organization, B.P. 549, Ouagadougou, Burkina Faso
| | - Nico JD Nagelkerke
- Department of Public Health, Erasmus University, Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
| | - Anton P Plaisier
- Department of Public Health, Erasmus University, Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
| | - Jan HF Remme
- World Health Organization, Geneva 27, Switzerland
| | | | - Gerard JJM Borsboom
- Department of Public Health, Erasmus University, Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
| | - J Dik F Habbema
- Department of Public Health, Erasmus University, Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
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Molyneux DH, Neira M, Liese B, Heymann D. Lymphatic filariasis: setting the scene for elimination. Trans R Soc Trop Med Hyg 2000; 94:589-91. [PMID: 11198635 DOI: 10.1016/s0035-9203(00)90198-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- D H Molyneux
- Lymphatic Filariasis Support Centre, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
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