Beating brucellosis and bovine tuberculosis |
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To boost livestock production and improve people's health, researchers in Tanzania have been working to increase people's knowledge of brucellosis and bovine tuberculosis - diseases which cause long-term illness in people and production losses in livestock. In Tanzania both diseases are a growing problem, and lack of knowledge is the major barrier to efforts to stop their spread. This work has involved identifying the groups most likely to be affected by the diseases and developing better ways of showing them how contamination can be avoided - such as boiling milk, and taking extra care when handling raw milk and placentas. Work to educate health practitioners and vets has also given good results, because diseases like brucellosis are often misdiagnosed and mistreated. Project Ref: AHP04:
RNRRS Programme; Animal Health Programme, Zoonoses cluster Relevant Research Projects:
Institutional partners: University of Edinburgh, Sokoine University of Agriculture, National Institute for Medical Research (all projects), Moredun Research Institute (R7229, R7357), Glasgow University (R7985, R7271), Liverpool University (R7985, R7271), Reading University (R7271).
The outputs are the identification of risk factors for TB/brucellosis and the identification of appropriate and effective knowledge dissemination methods for at-risk beneficiaries to (a) reduce the human health burden of these diseases in vulnerable populations, (b) improve productivity in their livestock and (c) empower the beneficiaries. Brucellosis and bovine tuberculosis are widespread throughout Tanzania and are a cause of growing concern for food security and public health, both as a cause of a debilitating illness in people and through production losses in livestock. For brucellosis, these losses arise as a result of abortions in cattle and small ruminants, whilst bovine tuberculosis results in loss of condition and carcass condemnations reducing income from sales and availability of meat. Although tuberculosis is one of the most important infectious diseases in Africa, prior to the RNRRS projects in Tanzania, almost nothing was known about the contribution of Mycobacterium bovis (the cause of bovine tuberculosis) to the human epidemic. Similarly, although brucellosis was known to occur in livestock in Tanzania, very little was known about the associated disease burden or risk factors for infection. Following conclusion of these RNRRS studies (2001-2004), quantitative data became available for the first time to assess the impact of bovine TB and brucellosis on human health, and to identify key at-risk populations and risk factors. Findings indicated that (a) pastoral and agropastoral communities were at greatest risk from bovine TB and brucellosis, and people with poor levels of knowledge living in remote, marginalised areas at particularly high risk from bovine TB; (b) bovine TB contributed substantially to the burden of human extra-pulmonary tuberculosis; (c) brucellosis affected 3% of people in pastoral and agropastoral communities, causing prolonged disability and a high DALY burden; (d) misdiagnosis of brucellosis was common and resulted in delayed and inappropriate treatment; (e) risk factors included consumption of raw milk and handling placental material. Additionally, the project established close integration between veterinary and public health sectors, with collaborative studies involving partnerships between researchers from the Sokoine University of Agriculture (SUA) and the National Institute of Medical Research (NIMR). Each project incorporated a substantial training element, with PhD training of both veterinary and medical students within the project. Substantial capacity building was achieved with establishment of laboratory facilities for culture and molecular diagnosis of bovine tuberculosis at SUA and NIMR and c-ELISA serology for brucellosis at SUA.
Livestock and livestock products Human productivity (agricultural and other, currently constrained by poor health)
Considerable value could be added by clustering this output with research outputs from several other key sources. Within the 'Research Into Use' initiative, these would include close links with other outputs within the Animal Health Programme cluster on zoonoses and dissemination and delivery. Links with the zoonoses cluster (rabies, R5406, and sleeping sickness, R7596, R8318) would strengthen existing veterinary-medical capacity, inter-sectoral integration and policy development for effective control of zoonotic diseases in East Africa. Links with the dissemination and delivery cluster would strengthen training on zoonoses within veterinary and medical curricula and help to develop continuing professional development (CPD), which is urgently needed to address the identified deficits in diagnosis, treatment and control of these zoonoses in Africa. Linkages with other RNRRS outputs have also provide important added-value with respect to information on effective dissemination methods and materials in different farming systems in Tanzania. For example, identification of appropriate dissemination methods will incorporate data generated from projects from small-holder dairy famers ("Optimising milk production in small-holder dairy farms in Tanzania", R7271) and livestock keepers in Uganda ("Treatment of cattle to eliminate the animal reservoir of T.b. rhodesiense", R8318). Further information on at-risk populations and dissemination methods for urban and peri-urban communities will be obtained from outputs derived from the DFID project ZXC0271 "An analysis of community health risk in relation to zoonoses from livestock keeping in a slum setting in Nairobi", a JICA/DFID collaborative project on "Urban and Peri-urban Livestock Farming in Uganda" and a EU-funded project (EDF 7, 6157 REG) on the risks associated with bovine tuberculosis and brucellosis in West Africa. How the outputs were validated: The outputs have been adopted at various levels and by various groups, including end-users, district-level hospitals, government departments, intermediary organisations and international agencies. In terms of end-users, an awareness of disease risks and willingness to adopt disease control measures was apparent among pastoral and agropastoral farmers during the research studies. More than 50% of farmers took up advice regarding removal of TB-infected animals (results from longitudinal studies - DFID final report, R7357). The results were replicated in studies of brucellosis in Manyara and Dodoma regions, with test-and-slaughter control strategies adopted on several high-incidence farms in high-potential systems (Dr. G. Shirima, Animal Diseases Research Institute). Evaluation of the impact of these measures on the incidence of disease or productivity in livestock, or human disease, has not yet been carried out. Uptake of outputs was also apparent among hospital medical officers within the study hospitals, with improved and enhanced diagnostic testing of suspected brucellosis patients (PhD study, NIMR, Kunda, 2006). These results have not yet been replicated in other parts of Tanzania, nor have their impacts in terms of reduced disease and disability burden been evaluated. Dissemination messages have been adopted by several intermediate agencies (e.g. Wren Media, BBC World), with development of articles and radio programmes on public health issues relating to brucellosis/TB for dissemination in Africa (2003-2005). Zoonoses leaflets incorporating information on prevention of brucellosis/TB have been developed and distributed in collaboration with other projects (e.g. rabies projects in Tanzania - see zoonoses cluster, R5406). Capacity-building has been validated in the form of quality control for laboratory diagnostic methods, with bovine TB diagnostic tests in Tanzania validated by the Moredun Research Institute (DFID final report, R7357, 2001) and the c-ELISA results for brucellosis diagnosis validated at the brucellosis reference laboratory, Veterinary Laboratories Agency, UK. The identification of at-risk populations (e.g. pastoralists for brucellosis) and risk factors (e.g. raw milk consumption for bovine TB and brucellosis, handling placentae/assisted calving for brucellosis) has been validated through peer-reviewed publications (Mfinanga et al., 2004; Shirima, 2005; Cleaveland et al., 2006; Kunda, 2006 - see Bibliography in Annex C for details). The institutional outputs of the projects have been evaluated in several reports, including: Shaw and Sibanda (2000) as part of a DFID evaluation; Coleman (2002) evaluating the impact of zoonotic disease on the poor; WHO/DFID (2005) in relation to control of neglected diseases and poverty alleviation. Institutional impacts relate principally to increased awareness within WHO and collaboration among different sectors in Tanzania, resulting in formal establishment of an inter-ministerial commission on zoonoses and recognition of zoonosis research and control as a priority for NIMR (2005). More formal evaluation of outputs of potential dissemination methods and material have been conducted by the small-holder dairy project (R7271), using a randomised controlled trial and validated by peer-review publications (Bell et al., 2006) to evaluate three knowledge dissemination methods (a diagrammatic handout, video and village meeting). Relevant to these outputs is the validation of local radio as an effective way of communicating health messages, which was carried out by the sleeping sickness project (R8318) in collaboration with Wren Media and local partners in Uganda. Where the Outputs were Validated: R7229, R7357: Most of the validation has taken place in northern Tanzania, in three regions (Manyara, Arusha and Mara) with livestock-keepers and medical officers being the principal target group. Advice concerning disease control in livestock has been adopted in agropastoral and pastoral communities, involving semi-arid and high potential systems, and a range of farming systems including smallholder rainfed dry/cold and smallholder rainfed humid. Advice on removal of infected animals was taken up by livestock owners from 2000-2004, diagnostic advice was taken up clinicians in district hospitals from 2004 to the present date. R7271: This study was carried out in Tanga and Iringa regions in Tanzania between 1999 and 2002. In Tanga, the study involved 256 smallholder dairy farmers in 36 villages (12 each in rural, peri-urban and urban areas). Tanga region comprises nine agro-ecological zones, and can be subdivided into areas of low, medium and high potential for dairying, primarily comprising smallholder rainfed humid systems. The study in Iringa region involved 110 farmers in 28 different villages, (11 rural, 8 peri-urban and 9 urban). Iringa region comprises two different agro-ecological zones, including high-potential zones, and smallholder rainfed humid and smallholder rainfed highland systems. Results showed no significant difference between respondents in rural, peri-urban or urban areas, suggesting that the knowledge dissemination methods used were appropriate for beneficiaries in each of these areas. These studies were carried out from 1997-2000. R8318: Messaging outputs in Uganda were validated in Soroti District and Mukono District, involving high potential and peri-urban smallholder rainfed farming systems during early 2000s. Who are the Users? The outputs are currently being used by: The World Health Organization is using quantitative data on brucellosis/bovine TB from Tanzania to inform estimates of the global burden of food-borne diseases The Tanzanian Government (Ministry of Health, Ministry of Livestock Development, Ministry of Natural Resources and Tourism) has greater awareness of the importance of intersectoral collaboration, the need for information on zoonotic diseases, and increased capacity through post-graduate training of medical and veterinary staff in zoonotic disease investigation. Tanzanian research institutions (SUA/NIMR) are using the diagnostic methods developed to provide reliable results for detection of brucellosis and bovine tuberculosis in human and animal populations. Livestock-keepers on several large farms with a high incidence of brucellosis are currently using test-and-slaughter methods to control the disease. The Livestock-for-Life programme (Wellcome Trust) is using a bovine tuberculosis network in sub-Saharan Africa based on the model of the Tanzanian study for integrating sectors and capacity building. Medical officers within district hospitals are now trained to recognise clinical signs that require laboratory testing for brucellosis. Some members of the general public, including livestock-keepers are now aware of the importance of boiling milk to reduce disease risks. This has been achieved with large mural displays, leaflet distribution and household-level discussions. Where the outputs have been used: The Livestock-for-Life bovine TB programme is operating in sub-Saharan Africa, including Tanzania, Kenya, Uganda, Senegal, Mali, Mauritania, Côte d'Ivoire, Burkina Faso, Chad, Ethiopia, South Africa, Cameroon (PSA countries highlighted). District hospitals with improved brucellosis recognition are in the study regions of Manyara and Arusha, northern Tanzania. Livestock keepers adopting test-and-slaughter disease control methods are in Dodoma and Manyara regions, Tanzania (high-potential systems). Public awareness murals are placed in key locations in Arusha and Manyara region, Tanzania, including urban and rural district centres (e.g. Arusha, Babati); and leaflets have been distributed in Arusha region. Scale of Current Use: Dissemination messages that address the zoonotic health risks (through leaflets, murals, radio broadcasts and household/hospital discussions) were rapidly adopted in the study areas (during the duration of project activities), but were (and are) geographically limited to the study areas only as a result of the limited 3-year timescale and funding available within the projects. Although these dissemination activities have not been maintained beyond the end of the research projects, the knowledge acquired is expected to persist for several years, although there is no doubt that dissemination needs to be reinforced at regular intervals. The governmental and institutional impacts have been widely adopted and are expanding in use due to dissemination through the World Health Organization and the Wellcome Trust Livestock-for-Life programme. The uptake of outputs on disease burden occurred relatively rapidly (e.g. 2002 Coleman report on zoonotic disease impacts on the poor), and continues to be used (e.g. in the 2006 initiative by WHO for the global estimation of food-borne diseases) Policy and Institutional Structures, and Key Components for Success: The principal platforms that have assisted with the promotion of outputs and capacity building include: Meetings and workshops bringing together different institutions across different sectors, including DFID zoonosis meeting (Nairobi, 2005)), NIMR annual conference that incorporated a full-day on zoonosis research outputs (2005), and WHO/DFID workshops (2005). Inter-sectoral collaboration. The establishment of an inter-ministerial commission on zoonoses has raised the profile of this group of diseases. Memoranda of understanding established between the veterinary and medical research sectors in Tanzania (SUA/NIMR) and collaborative engagement at all levels, including field studies, hospital research and laboratory diagnostic activities has been invaluable. Capacity-building to provide the appropriate laboratory facilities at both NIMR and SUA and training of medical/veterinary staff at both institutions. Postgraduate and professional training for both medical and veterinary researchers in Tanzania (5 Tanzanian PhDs obtained through UK Universities, MSc training in Tanzania, technical laboratory training both in Tanzania and overseas). Freedom for researchers to develop research outputs on return to Tanzania (e.g. Prof. Kazwala, Dr. Mfinganga) and to continue to act as advocates for zoonoses prevention and control. Lessons Learned and Uptake Pathways Promotion of Outputs: For bovine tuberculosis, promotion in Tanzania is focused towards a full assessment of the true human disease burden, with completion of a DFID project on quantifying the contribution of bovine tuberculosis to human cases of pulmonary tuberculosis ("Quantifying the prevalence of Mycobacterium bovis in human pulmonary tuberculosis in Tanzania"). Outputs from the earlier RNRRS projects are being promoted on a wider geographic scale through the Livestock-for-Life project "Effective management of bovine tuberculosis in sub-Saharan Africa" funded by the Wellcome Trust, which aims to promote capacity-building, strengthen public education, and promote safe consumption of milk through partnerships with key stakeholders in a wide range of countries in East and West Africa. This is planned to cover the period 2006-2010. Very little specific promotion on brucellosis is currently taking place in Tanzania or elsewhere in Africa. Potential Barriers Preventing Adoption of Outputs:
How to Overcome Barriers to Adoption of Outputs:
Lessons Learned: Without empowerment, there is a risk that key end-users will be missed, including women (preparation of milk), remote and assetless poor, pastoralists and semi-nomadic communities without well-defined institutional access. Linking changing practices to direct benefits, provides an incentive for change, as seen with rabies control measures whereby communities recognised the link between dog vaccination and the control of rabies in their communities. In general, people are eager to access knowledge and learn about disease risks, but must be given the opportunity to do so. Beneficiaries should be sensitised to outputs prior to actual dissemination of messages. For example, campaigns could start with a branded awareness campaign and then move onto actual dissemination of key messages, such as 'boil all milk'. Radio messaging has been demonstrated as an effective means of disseminating public health messages relating to sleeping sickness in rural Uganda, and is not limited to households having ownership of radios as messages can be delivered through radios in public locations. Piloting of dissemination materials is essential to ensure that local situations and images are depicted in all materials (to aid recognition), and ensure that all messages are locally relevant. Schools and school children have proved an effective route of dissemination for rabies and sleeping sickness, with messages not only reaching the target child audience (in the case of rabies risks), but also resulting in feedback to adults in the household. Awareness of health benefits of a given measure can create demand from the community, generating political will (e.g. rabies control in Tanzania) and a demand for supply of healthy products (e.g. premiums could be paid for pasteurised milk). Poverty Impact Studies: To date, most impact of the brucellosis/TB projects has been at institutional level, with little direct impact on poverty. Where current impacts exist, these are geographically limited to the study areas in northern Tanzania and relate to improved diagnosis and treatment of brucellosis cases. This is expected to have reduced the burden of disease and disability, as well as the costs of treatment, but these impacts have not been formally quantified. The impact of 'boiling milk' messages and other measures to prevent zoonoses has not been evaluated in terms of impact on poverty or human health. Most of the studies listed relate to evaluating disease burden and identifying at-risk populations:
How the Poor have Benefited (including gender and other poverty groups): Little quantitative evidence is available to demonstrate how adoption of the outputs has benefited the poor. The outputs have been adopted in only limited geographic areas and, although these are anticipated to have had an impact as described above, little quantitative data are available. Empowerment of farmers through increased knowledge was quantified as part of the smallholder dairy project, with an anticipated improvement in livestock health and productivity resulting from changes in milking practices, however this has not been quantified in terms of poverty impact. Direct and Indirect Environmental Benefits: In the past, deterioration in livestock production has led to a significant expansion of cultivation in wildlife areas (e.g. Ngorongoro, Tarangire) leading to disruption of wildlife migration patterns and degradation of important habitats. Improved livestock productivity in pastoralist areas will have beneficial environmental impacts by reducing land-use pressure in ecologically-sensitive areas, such as the Ngorongoro Conservation Area, which is a World Heritage Site located in a high-risk area for brucellosis and tuberculosis. Control of brucellosis and bovine tuberculosis in livestock is likely to have direct benefits for wildlife, reducing the risk of transmission from cattle to wildlife in areas with high rates of contact between livestock and wildlife (e.g. Arusha Region). Several important wildlife populations in Tanzania (buffalo, impala) are known to be infected with brucellosis, which may have contributed to population declines in the past (e.g. Serengeti buffalo). Although the impact of bovine tuberculosis on Tanzanian wildlife is not known, the infection is widespread in the national parks and potential effects may be severe, given the devastating outcome of bovine tuberculosis infection in Kruger National Park wildlife. Adverse Environmental Impacts: The only anticipated adverse environmental impacts relate to the increased demand for fuel for boiling milk and burning placental material, which may increase deforestation rates in some areas. In the absence of protective clothing (gloves) the use of plastic bags may be promoted as a means of protecting hands from contamination during handling of placental material, which may increase litter volume (or alternatively may provide an additional value and use for plastic bags which may decrease litter volume). Coping with the Effects of Climate Change, or Risk from Natural Disasters: There are no anticipated impacts other than the reduced burden of illness and disability. ANNEX C. Bibliography Anderson, D.M. and Broch-Due, V. (1999) The Poor Are Not Us: Poverty and Pastoralism. Oxford University Press, Oxford. Bell, C.E. (2002) Development and evaluation of knowledge dissemination methods for smallholder dairy farmers in Tanzania, with special reference to bovine mastitis, PhD Thesis, University of Glasgow. Bell, C.E., French, N.P., Karimuribo, E., Ogden, N.H., Bryant, M.J., Swai, E.M., Kambarage, D.M., Fitzpatrick, J.L.(2005) The effects of different knowledge-dissemination interventions on the mastitis knowledge of Tanzanian smallholder dairy farmers, Preventive Veterinary Medicine, 72: 237-251. Cleaveland, S., Shaw, D.J., Shirima, G., Kazwala, R.R., Mfinanga, S.G, Eblate, E. and Sharp, M. (2006) Mycobacterium bovis in rural Tanzania: risk factors and patterns of infection in human and cattle populations. Tuberculosis (In press). Cleaveland S., Mlengeya T., Kazwala R.R., Michel A., Kaare M.T, Jones S.L., Eblate E., Shirima G.M. and Packer C. (2005) Tuberculosis in Tanzanian wildlife. Journal of Wildlife Diseases 41(2): 446-453. Coleman, P. (2002) Zoonotic diseases and their impact on the poor. In: Perry, B.D., Randolh, T.F., McDermott, J.J., Sones, K.R. and Thornton, P.K. (2002) Investing in animal health research to alleviate poverty. International Livestock Research Institute (ILRI), Nairobi, Kenya. Karimuribo, E.D., Fitzpatrick, J.L., Bell, C.E., Swai, E.S., Kambarage, D.M., Ogden, N.H., Bryant, M.J. and French, N.P. (2006) Clinical and subclinical mastitis in smallholder dairy farms in Tanzania: risk, intervention and knowledge transfer, Preventive Veterinary Medicine, 74: 84-98. Kunda J., Cleaveland S., Fitzpatrick J., French N., Kambarage D., Shirima G. and Kazwala R.R. (2005) Brucellosis in Arusha and Manyara Regions, Tanzania: a challenge to public health. Tanzania Medical Journal, 19 (2). Kunda J. (2006) Kunda, J. (2006) The epidemiology of human brucellosis in northern Tanzania, with reference to other zoonotic diseases. PhD Thesis, University of Edinburgh McCabe J.T., Schofield E.C. and Nygaard Pederson G. (1997) Food security and nutritional status. In: Multiple land-use: the experience of the Ngorongoro Conservation Area, Tanzania (ed. D.M. Thompson), IUCN-The World Conservation Union, Gland, Switzerland, pp. 285-301. Mfinanga S.G.M., Morkve O., Kazwala R.R., Cleaveland S., Kunda J., Sharp M.J. and Nilsen R. (2004) Mycobacterial adenitis: role of Mycobacterium bovis, non-tuberculous Mycobacteria, HIV infection and risk factors in Arusha, Tanzania. East African Medical Journal, 81. (4):171-8. Mfinanga S.G, Morkve O,.Kazwala R.R, Cleaveland, S,.Sharp J. M, Shirima G, Nilsen R. (2003) Tribal difference in perception of tuberculosis: A possible role in tuberculosis control in Arusha, Tanzania. Int J Tuberc Lung Dis 7 (10): 933-941. Mfinanga S.G, Morkve O, Kazwala R. R, Cleaveland S, Sharp J.M, Shirima G, Nilsen R. (2003) The role of livestock-keeping in tuberculosis trends in Arusha, Tanzania. Int J Tuberc Lung Dis: 7(7):695 - 704. Shaw, A. and Sibanda, L. (2000) Evaluation of selected livestock research themes 1988-1999. Final Report for DFID. Landell Mills Ltd. Shirima, G. (2005) The epidemiology of brucellosis in animals and humans in Arusha and Manyara Regions of Tanzania. PhD Thesis, University of Glasgow. WHO/DFID (2005) The control of neglected zoonotic diseases: a route to poverty alleviation. World Health Organization (WHO)/DIFD, Geneva, Switzerland and DFID-Animal Health Programme (AHP). Relevant Research Projects,
with links to the
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For relevant research projects, with links to further information Geographical regions included: Burkina Faso, Cameroon, Chad, Cote d'Ivoire, Ethiopia, Kenya, Mali, Mauritania, Senegal, South Africa, Tanzania, Uganda,  Target Audiences for this content:Livestock farmers, |
