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Beyene TJ, Mourits M, O'Quin J, Leta S, Baruch J, Hogeveen H. Policy Perspectives of Dog-Mediated Rabies Control in Resource-Limited Countries: The Ethiopian Situation. Front Vet Sci 2020; 7:551. [PMID: 32984411 PMCID: PMC7493619 DOI: 10.3389/fvets.2020.00551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/13/2020] [Indexed: 12/25/2022] Open
Abstract
One Health disease-control programs are believed to be most effective when implemented within the population transmitting the disease. The World Health Organization (WHO) and partners have targeted the elimination of dog-mediated human rabies by 2030 primarily through mass dog vaccination. Mass vaccination, however, has been constrained by financial resource limitations. The current owner-charged dog vaccination strategy, used in most resource-limited countries like Ethiopia, has not reached the minimum coverage required to build population immunity. Dog vaccination is non-existing in most rural areas of Ethiopia, and coverage is <20% in urban areas. Although the health and economic benefits of rabies elimination outweigh the costs, the direct beneficiaries (public in general) and those who bear the costs (dog owners) are not necessarily the same. In this perspective paper, we aggregate evidence on the socioeconomic burden of rabies in Ethiopia as well as the implications for potential opportunities to control the disease and possibilities to obtain the required funding sources for evidence-based interventions in the control of rabies in Ethiopia.
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Affiliation(s)
- Tariku Jibat Beyene
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Monique Mourits
- Business Economics Group, Wageningen University, Wageningen, Netherlands
| | - Jeanette O'Quin
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Samson Leta
- College of Veterinary Medicine and Agriculture, Addis Ababa University, Addis Ababa, Ethiopia
| | - Joaquin Baruch
- Department of Diagnostic Medicine and Pathobiology and Center for Outcomes Research and Epidemiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
| | - Henk Hogeveen
- Business Economics Group, Wageningen University, Wageningen, Netherlands
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Baker CH, Welburn SC. The Long Wait for a New Drug for Human African Trypanosomiasis. Trends Parasitol 2018; 34:818-827. [DOI: 10.1016/j.pt.2018.08.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/07/2018] [Accepted: 08/08/2018] [Indexed: 12/22/2022]
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Yahyaoui Azami H, Ducrotoy MJ, Bouslikhane M, Hattendorf J, Thrusfield M, Conde- Álvarez R, Moriyón I, Zúñiga-Ripa A, Muñoz Álvaro PM, Mick V, Bryssinckx W, Welburn SC, Zinsstag J. The prevalence of brucellosis and bovine tuberculosis in ruminants in Sidi Kacem Province, Morocco. PLoS One 2018; 13:e0203360. [PMID: 30226847 PMCID: PMC6143194 DOI: 10.1371/journal.pone.0203360] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 08/20/2018] [Indexed: 12/12/2022] Open
Abstract
Bovine tuberculosis (BTB) and brucellosis are major endemic zoonoses in ruminants in Morocco that impact on both animal and human health. This study presents an assessment of the epidemiological and socioeconomic burden of bacterial zoonoses in Sidi Kacem Province in Northern Morocco from a cross-sectional survey of 125 cattle and/or small ruminant-owning households. In total, 1082 sheep and goats were examined from 81 households. The single intradermal comparative cervical test to screen for bovine tuberculosis was undertaken on 1194 cattle from 123 households and all cattle were blood sampled. Cattle and small ruminant sera were tested for brucellosis using the standard Rose Bengal Test (sRBT) and the modified Rose Bengal Test (mRBT). Bacteriology was performed on 21 milk samples obtained from cattle that were seropositive for brucellosis for isolation and phenotyping of circulating Brucella strains. Individual and herd prevalence for BTB in cattle of 20.4% (95% CI 18%-23%) and 57.7% (95% CI 48%-66%), respectively, were observed in this study. The prevalence of brucellosis in cattle at individual and herd level was 1.9% (95% CI 1.2%-2.8%) and 9% (95% CI 4.5%-1.5%), respectively. Brucella pathogens were isolated from three cattle milk samples and were identified as B. abortus using Bruceladder® multiplex PCR and B. abortus biovar 1 by classical phenotyping. All small ruminants were seronegative to sRBT, two were positive to mRBT. A higher risk of BTB and brucellosis was observed in cattle in intensive livestock systems, in imported and crossed breeds and in animals from larger herds (>15). The three risk factors were usually present in the same herds, leading to higher transmission risk and persistence of both zoonoses. These results highlight the importance of implementing control strategies for both BTB and brucellosis to reduce productivity losses and the risk of transmission to humans. Prioritising control for BTB and brucellosis in intensive livestock production systems is essential for human and animal health.
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Affiliation(s)
- Hind Yahyaoui Azami
- Department of Veterinary Pathology and Public Health, Agronomic and Veterinary Institute Hassan II, Rabat, Maroc
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Marie J. Ducrotoy
- Division of Infection and Pathway Medicine, Centre for Infectious Diseases, School of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Mohammed Bouslikhane
- Department of Veterinary Pathology and Public Health, Agronomic and Veterinary Institute Hassan II, Rabat, Maroc
| | - Jan Hattendorf
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Mike Thrusfield
- Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | - Raquel Conde- Álvarez
- IDISNA - Instituto de Salud Tropical y Depto. Microbiología y Parasitología, Universidad de Navarra, Edificio de Investigación, Pamplona, Spain
| | - Ignacio Moriyón
- IDISNA - Instituto de Salud Tropical y Depto. Microbiología y Parasitología, Universidad de Navarra, Edificio de Investigación, Pamplona, Spain
| | - Amaia Zúñiga-Ripa
- IDISNA - Instituto de Salud Tropical y Depto. Microbiología y Parasitología, Universidad de Navarra, Edificio de Investigación, Pamplona, Spain
| | - Pilar M. Muñoz Álvaro
- Unidad de Producción y Sanidad Animal, Instituto Agroalimentario de Aragón– IA2 - (CITA-Universidad de Zaragoza), Zaragoza, Spain
| | - Virginie Mick
- Paris-Est University/Anses, EU/OIE/FAO & National Reference Laboratory for brucellosis, Animal Health Laboratory, Maisons-Alfort, France
| | | | - Sue C. Welburn
- Division of Infection and Pathway Medicine, Centre for Infectious Diseases, School of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Jakob Zinsstag
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Gibson AD, Mazeri S, Lohr F, Mayer D, Burdon Bailey JL, Wallace RM, Handel IG, Shervell K, Bronsvoort BM, Mellanby RJ, Gamble L. One million dog vaccinations recorded on mHealth innovation used to direct teams in numerous rabies control campaigns. PLoS One 2018; 13:e0200942. [PMID: 30048469 PMCID: PMC6062050 DOI: 10.1371/journal.pone.0200942] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 07/05/2018] [Indexed: 12/25/2022] Open
Abstract
Background Canine transmitted rabies kills an estimated 59,000 people annually, despite proven methods for elimination through mass dog vaccination. Challenges in directing and monitoring numerous remote vaccination teams across large geographic areas remain a significant barrier to the up-scaling of focal vaccination programmes to sub-national and national level. Smartphone technology (mHealth) is increasingly being used to enhance the coordination and efficiency of public health initiatives in developing countries, however examples of successful scaling beyond pilot implementation are rare. This study describes a smartphone app and website platform, “Mission Rabies App”, used to co-ordinate rabies control activities at project sites in four continents to vaccinate over one million dogs. Methods Mission Rabies App made it possible to not only gather relevant campaign data from the field, but also to direct vaccination teams systematically in near real-time. The display of user-allocated boundaries on Google maps within data collection forms enabled a project manager to define each team’s region of work, assess their output and assign subsequent areas to progressively vaccinate across a geographic area. This ability to monitor work and react to a rapidly changing situation has the potential to improve efficiency and coverage achieved, compared to regular project management structures, as well as enhancing capacity for data review and analysis from remote areas. The ability to plot the location of every vaccine administered facilitated engagement with stakeholders through transparent reporting, and has the potential to motivate politicians to support such activities. Results Since the system launched in September 2014, over 1.5 million data entries have been made to record dog vaccinations, rabies education classes and field surveys in 16 countries. Use of the system has increased year-on-year with adoption for mass dog vaccination campaigns at the India state level in Goa and national level in Haiti. Conclusions Innovative approaches to rapidly scale mass dog vaccination programmes in a sustained and systematic fashion are urgently needed to achieve the WHO, OIE and FAO goal to eliminate canine-transmitted human deaths by 2030. The Mission Rabies App is an mHealth innovation which greatly reduces the logistical and managerial barriers to implementing large scale rabies control activities. Free access to the platform aims to support pilot campaigns to better structure and report on proof-of-concept initiatives, clearly presenting outcomes and opportunities for expansion. The functionalities of the Mission Rabies App may also be beneficial to other infectious disease interventions.
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Affiliation(s)
- Andrew D. Gibson
- Mission Rabies, Cranborne, Dorset, United Kingdom
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, Division of Genetics and Genomics, The University of Edinburgh, Hospital for Small Animals, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | - Stella Mazeri
- Mission Rabies, Cranborne, Dorset, United Kingdom
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, Division of Genetics and Genomics, The University of Edinburgh, Hospital for Small Animals, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | | | - Dagmar Mayer
- Worldwide Veterinary Service, Cranborne, Dorset, United Kingdom
| | | | - Ryan M. Wallace
- Poxvirus and Rabies Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Ian G. Handel
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, Division of Genetics and Genomics, The University of Edinburgh, Hospital for Small Animals, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | | | - Barend M.deC. Bronsvoort
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, Division of Genetics and Genomics, The University of Edinburgh, Hospital for Small Animals, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | - Richard J. Mellanby
- The Royal (Dick) School of Veterinary Studies, Division of Veterinary Clinical Studies, The University of Edinburgh, Hospital for Small Animals, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
- * E-mail: (RJM); (LG)
| | - Luke Gamble
- Mission Rabies, Cranborne, Dorset, United Kingdom
- Worldwide Veterinary Service, Cranborne, Dorset, United Kingdom
- * E-mail: (RJM); (LG)
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Krafsur ES, Maudlin I. Tsetse fly evolution, genetics and the trypanosomiases - A review. INFECTION GENETICS AND EVOLUTION 2018; 64:185-206. [PMID: 29885477 DOI: 10.1016/j.meegid.2018.05.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/30/2018] [Accepted: 05/31/2018] [Indexed: 01/27/2023]
Abstract
This reviews work published since 2007. Relative efforts devoted to the agents of African trypanosomiasis and their tsetse fly vectors are given by the numbers of PubMed accessions. In the last 10 years PubMed citations number 3457 for Trypanosoma brucei and 769 for Glossina. The development of simple sequence repeats and single nucleotide polymorphisms afford much higher resolution of Glossina and Trypanosoma population structures than heretofore. Even greater resolution is offered by partial and whole genome sequencing. Reproduction in T. brucei sensu lato is principally clonal although genetic recombination in tsetse salivary glands has been demonstrated in T. b. brucei and T. b. rhodesiense but not in T. b. gambiense. In the past decade most genetic attention was given to the chief human African trypanosomiasis vectors in subgenus Nemorhina e.g., Glossina f. fuscipes, G. p. palpalis, and G. p. gambiense. The chief interest in Nemorhina population genetics seemed to be finding vector populations sufficiently isolated to enable efficient and long-lasting suppression. To this end estimates were made of gene flow, derived from FST and its analogues, and Ne, the size of a hypothetical population equivalent to that under study. Genetic drift was greater, gene flow and Ne typically lesser in savannah inhabiting tsetse (subgenus Glossina) than in riverine forms (Nemorhina). Population stabilities were examined by sequential sampling and genotypic analysis of nuclear and mitochondrial genomes in both groups and found to be stable. Gene frequencies estimated in sequential samplings differed by drift and allowed estimates of effective population numbers that were greater for Nemorhina spp than Glossina spp. Prospects are examined of genetic methods of vector control. The tsetse long generation time (c. 50 d) is a major contraindication to any suggested genetic method of tsetse population manipulation. Ecological and modelling research convincingly show that conventional methods of targeted insecticide applications and traps/targets can achieve cost-effective reduction in tsetse densities.
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Affiliation(s)
- E S Krafsur
- Department of Entomology, Iowa State University, Ames, IA 50011, USA.
| | - Ian Maudlin
- School of Biomedical Sciences, The University of Edinburgh, Scotland, UK
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Muhanguzi D, Mugenyi A, Bigirwa G, Kamusiime M, Kitibwa A, Akurut GG, Ochwo S, Amanyire W, Okech SG, Hattendorf J, Tweyongyere R. African animal trypanosomiasis as a constraint to livestock health and production in Karamoja region: a detailed qualitative and quantitative assessment. BMC Vet Res 2017; 13:355. [PMID: 29178951 PMCID: PMC5702144 DOI: 10.1186/s12917-017-1285-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 11/17/2017] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Nagana (African Animal Trypanosomiasis-AAT) and tick-borne diseases (TBDs) constrain livestock production in most parts of sub-Saharan Africa. To this realisation, Uganda government set up an African trypanosomiasis (AT) control unit, which among other activities generates national tsetse control priority maps using apparent tsetse density data. Such maps underestimate mechanically transmitted AAT and thus ought to be refined using actual AT prevalence data. We therefore set out to generate up-to-date cattle and donkey trypanosomiasis prevalence data as well as find out the constraints to livestock production in Karamoja region in a bid to re-define AT control priority in this region. RESULTS Livestock keepers and animal health workers indicated that TBDs and AAT were the most important livestock diseases in Karamoja region. The prevalence of Trypanosoma spp. in cattle and donkeys was 16.3% (95% CI: 12.4-21.1%) and 32.4% (95% CI; 20.2-47.6%) respectively. Trypanosoma vivax (12.1%) and Trypanosoma congolense savannah (29.6%) were the most prevalent Trypanosoma spp. in cattle and donkeys respectively. Majority of the cattle (85.7%) and more than half of the donkey (57.1%) herds were positive for Trypanosoma spp. CONCLUSIONS African animal trypanosomiasis and TBDs are the most important constraints to livestock production in Karamoja region. In order to improve livestock production and hence Karamajong livelihoods, government of Uganda and her development partners will need to invest in livestock health programs particularly targeting tsetse and TBD control.
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Affiliation(s)
- Dennis Muhanguzi
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Albert Mugenyi
- Coordinating Office for Control of Trypanosomiasis in Uganda, Ministry of Agriculture, Animal Industry and Fisheries, Plot 78, Buganda Road, P. O. Box: 16345 Wandegeya, Kampala, Uganda
| | - Godfrey Bigirwa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | | | - Ann Kitibwa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Grace Gloria Akurut
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Sylvester Ochwo
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Wilson Amanyire
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Samuel George Okech
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Jan Hattendorf
- Swiss Tropical Institute, Socinstrasse 57, -4002 Basel, CH Switzerland
- University of Basel, Petersplatz 1, 4003 Basel, Switzerland
| | - Robert Tweyongyere
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
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Welburn SC, Coleman PG, Zinsstag J. Rabies Control: Could Innovative Financing Break the Deadlock? Front Vet Sci 2017; 4:32. [PMID: 28337440 PMCID: PMC5343007 DOI: 10.3389/fvets.2017.00032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 02/20/2017] [Indexed: 12/25/2022] Open
Abstract
The neglected zoonotic diseases (NZDs) have been all but eradicated in wealthier countries but remain major causes of ill-health and mortality in over 80 countries across Africa, Asia, and Latin America. The nature of neglect for the NZDs has been ascribed, in part, to underreporting resulting in an underestimation of their global burden that, together with a lack of advocacy, downgrades their relevance to policy-makers and funding agencies. While this may be the case for many NZDs, for rabies this is not the case. The global burden estimates for rabies (931,600 DALYs) more than justify prioritizing rabies control building on the strong advocacy platforms, functioning at local, regional, and global levels (including the Global Alliance for Rabies Control), and commitments from WHO, OIE, and FAO. Simple effective tools for rabies control exist together with blueprints for operationalizing control, yet, despite elimination targets being set, no global affirmative action has been taken. Rabies control demands activities both in the short term and over a long period of time to achieve the desired cumulative gains. Despite the availability of effective vaccines and messaging tools, rabies will not be sustainably controlled in the near future without long-term financial commitment, particularly as disease incidence decreases and other health priorities take hold. While rabies control is usually perceived as a public good, public private partnerships could prove equally effective in addressing endemic rabies through harnessing social investment and demonstrating the cost-effectiveness of control. It is acknowledged that greater attention to navigating local realities in planning and implementation is essential to ensuring that rabies, and other neglected diseases, are controlled sustainably. In the shadows of resource and institutional limitations in the veterinary sector in low- and middle-income countries, sufficient funding is required so that top-down interventions for rabies can more explicitly engage with local project organization capacity and affected communities in the long term. Development Impact Bonds have the potential to secure the financing required to deliver effective rabies control.
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Affiliation(s)
- Susan C. Welburn
- Division of Infection and Pathway Medicine, Edinburgh Medical School: Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, UK
| | - Paul G. Coleman
- Faculty of Infectious and Tropical Diseases, Department of Disease Control, School of Hygiene & Tropical Medicine, London, UK
- H2O Venture Partners, Oxford, UK
| | - Jakob Zinsstag
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Fyfe J, Picozzi K, Waiswa C, Bardosh KL, Welburn SC. Impact of mass chemotherapy in domestic livestock for control of zoonotic T. b. rhodesiense human African trypanosomiasis in Eastern Uganda. Acta Trop 2017; 165:216-229. [PMID: 27570206 DOI: 10.1016/j.actatropica.2016.08.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 08/17/2016] [Accepted: 08/24/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Human African trypanosomiasis (HAT) comprises two fatal parasitic diseases. Uganda is home to both chronic T. b. gambiense (gHAT) and the acute zoonotic form T. b. rhodesiense (rHAT) which occur in two large but discrete geographical foci. The area affected by rHAT has been rapidly expanding due to importation of T. b. rhodesiense infected cattle into tsetse infested but previously HAT free districts. Migration of rHAT has resulted in a considerable human health burden in these newly affected districts. Here, we examined the impact of a single, district-wide, mass chemotherapeutic livestock intervention, on T. b. rhodesiense prevalence in cattle and on incidence and distribution of human rHAT cases in Kamuli and Soroti districts in eastern Uganda. METHODS A single mass intervention in domestic cattle (n=30,900) using trypanocidal drugs was undertaken in November and December 2002 under the EU funded Farming in Tsetse Controlled Areas (FITCA) programme. The intervention targeted removal of the reservoir of infection i.e. human infective T. b. rhodesiense parasites in cattle, in the absence of tsetse control. Interventions were applied in high-risk sub-counties of Kamuli district (endemic for rHAT) and Soroti district (where rHAT has been recently introduced). The prevalence of T. brucei s.l. and the human infective subspecies, T. b. rhodesiense in cattle (n=1833) was assessed before and 3 and 12 months after intervention using PCR-based methods. A combination of descriptive statistical analysis and spatial scan statistics were applied to analyse rHAT cases reported over a 5-year period (January 2000-July 2005). RESULTS A single intervention was highly effective at removing human infective T. b. rhodesiense parasites from the cattle reservoir and contributed to a significant decrease in human rHAT cases. Intervention coverage was higher in Kamuli (81.1%) than in Soroti (47.3%) district but despite differences in coverage both districts showed a reduction in prevalence of T. b. brucei s.l. and T. b. rhodesiense. In Kamuli, the prevalence of T. brucei s.l. decreased by 54%, from 6.75% to 3.11%, 3, months post-intervention, rising to 4.7% at 12 months. The prevalence of T. b. rhodesiense was 3% pre-intervention and no T. b. rhodesiense infections were detected 3 and 12, months post-treatment. In Soroti, the prevalence of T. brucei s.l. in cattle decreased by 38% (from 21% to 13%) 3 months after intervention decreasing to less than 10% at 12 months. The prevalence of T. b. rhodesiense was reduced by 50% at 12-months post-intervention (6%-3%). Most notably, was the impact of the intervention on the population dynamics between T. b. brucei and human infective T. b. rhodesiense. Before intervention in Kamuli district 56% of T. b. brucei s.l. circulating in cattle were T. b. rhodesiense; at both 3 and 12 months after intervention none of the re-infecting T. b. brucei s.l. were human infective, T. rhodesiense. For human rHAT cases, there was a seven-fold decrease in rHAT incidence after intervention in Kamuli district (5.54 cases/1,000 head of population 2000-2002 to 0.76 cases/1,000, 2003-2005). Incidence data suggests that the intervention had minimal impact on the number of rHAT cases in Soroti overall, but showed a significant decrease in the seasonal peak of cases in the year following treatment. CONCLUSION A single intervention, targeted at cattle, introduced at district level, in the absence of tsetse control, was highly effective at removing human infective rHAT parasites from the cattle reservoir and contributed to a significant decrease in human rHAT cases. The differential impacts observed between the two districts are related to both the different stages of rHAT endemicity in the districts, and levels of intervention coverage achieved in the cattle population. Treatment of cattle to remove the reservoir of rHAT infection offers a promising and cost effective approach for the control of rHAT. It is important that cattle are treated before relocation to prevent possible merger of the two HAT foci, which would complicate diagnosis and treatment of both gHAT and rHAT.
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