Spatial predictors of bovine tuberculosis infection and Brucella spp. exposure in pastoralist and agropastoralist livestock herds in the Ruaha ecosystem of Tanzania
- 381 Downloads
While many studies investigate animal-related risk factors for disease, few have considered environmental or spatial risk factors in the dynamics of bovine tuberculosis (bTB) and brucellosis. In the Ruaha ecosystem of Tanzania, we investigated the role of household location as a predictor for infection with Mycobacterium bovis and exposure to Brucella in pastoralist and agropastoralist cattle herds in a typical African wildlife-livestock-human interface. ArcGIS was utilized to calculate Euclidian distances between households and the nearest river, village center, protected area, and other infected households, followed by multivariate logistic regression to assess the association between risk factors and herd-level bTB and Brucella outcomes. Global and local spatial clustering of bTB-infected and Brucella-exposed herds was explored using the Cuzick-Edward’s test and SaTScan spatial scan statistics. Households located farther from rivers and closer to village centers and herds belonging to agropastoralists were more likely to have bTB-positive cattle. Risk of Brucella exposure increased with proximity to protected areas. One spatial cluster of households with Brucella spp. seropositive cattle was identified. Spatial factors may be useful for assessing disease risk and for formulating intervention and control strategies for households that manage cattle in ecosystems characterized by seasonally limited resources and intense wildlife-livestock interfaces.
KeywordsBovine tuberculosis Brucellosis Cattle Spatial predictors Tanzania
This research was part of the Health for Animals and Livelihood Improvement (HALI) Project, a One Health project addressing zoonotic diseases in Tanzania, and was funded by the Global Livestock Collaborative Research Support Program by the Office of Agriculture, Bureau for Economic Growth, Agriculture and Trade, United States Agency for International Development under the terms of Grant No. PCE-G-00-98-00036-00. Special thanks go to Howard Kombe who assisted with household interviews and testing of cattle; to Jonas Fitwangile, Ali Kitime, and Kuleng’wa Ndaki Lukiko for laboratory assistance; and to Laurel Beckett, Esthe Geraghty, and Kate Thomas for their advice on statistical analysis and mapping.
Conflict of interest
The authors declare that they have no conflict of interest.
- Alvarez, J., Perez, A., Bezos, J., Marques, S., Grau, A., Saez, J. L., Minguez, O., de Juan, L. and Dominguez, L., 2012. Evaluation of the sensitivity and specificity of bovine tuberculosis diagnostic tests in naturally infected cattle herds using a Bayesian approach, Veterinary Microbiology, 155, 38-43PubMedCrossRefGoogle Scholar
- Clifford, D.L., Kazwala, R.R., Sadiki, H., Roug, A., Muse, E.A., Coppolillo, P.C. and Mazet, J.A.K., 2013. Tuberculosis infection in wildlife from the Ruaha ecosystem Tanzania: implications for wildlife, domestic animals, and human health, Epidemiology and Infection, doi: 10.1017/S0950268813000836 PubMedGoogle Scholar
- Coppolillo, P., Clifford, D. L. and Mazet, J. A. K., 2008. The unintended consequences of development assistance: The case of Usangu in Tanzania, Research Brief 08-02-HALI. Global Livestock Collaborative Research Support Program (CRSP). Available: http://glcrsp.ucdavis.edu/publications/?project=hali. Accessed February 4th, 2014.
- Coppolillo, P., Clifford, D., Dickman, A., Masozera, M., Nguvava, M., Kazwala, R., Erickson, J. and Mazet, M., 2009. Landscape factors associated with livestock disease deaths in Idodi and Pawaga Divisions, Tanzania, Research Brief 09-01-HALI. Global Livestock Collaborative Research Support Program (GLCRP). Available: http://glcrsp.ucdavis.edu/publications/?project=hali. Accessed February 4th, 2014.
- Courtenay, O., Reilly, L.A., Sweeney, F.P., Hibberd, V., Bryan, S., Ul-Hassan, A., Newman, C., Macdonald, D.W., Delahay, R.J., Wilson, G.J. and Wellington, E.M., 2006. Is Mycobacterium bovis in the environment important for the persistence of bovine tuberculosis? Biology Letters, 2, 460-462PubMedCentralPubMedCrossRefGoogle Scholar
- Cuzick, J. and Edwards, R., 1990. Spatial clustering for inhomogeneous populations, Journal of the Royal Statistical Society, Series B, 52, 73 -104Google Scholar
- de la Rua-Domenech, R., Goodchild, A. T., Vordermeier, H. M., Hewinson, R. G., Christiansen, K. H. and Clifton-Hadley, R. S., 2006. Ante mortem diagnosis of tuberculosis in cattle: A review of the tuberculin tests, [gamma]-interferon assay and other ancillary diagnostic techniques, Research in Veterinary Science, 81, 190-210PubMedCrossRefGoogle Scholar
- De Vos, V., Bengis, R.G., Kriek, N.P., Michel, A., Keet, D.F., Raath, J.P. and Huchzermeyer, H.F., 2001. The epidemiology of tuberculosis in free-ranging African buffalo (Syncerus caffer) in the Kruger National Park, South Africa, Onderstepoort Journal of Veterinary Research, 68, 119-130Google Scholar
- Godfroid, J., 2002. Brucellosis in wildlife, Revue Scientifique et Technique Office International des Epizooties, 21, 277-286Google Scholar
- Homewood, K. 2008. Ecology of African pastoralist societies, Ohio University Press Athens, OH, USAGoogle Scholar
- Jiwa, S.F.H., Kazwala, R.R., Tungaraza, R., Kimera, S.I. and Kalaye, W.J., 1996. Bovine brucellosis serum agglutination test prevalence and breed disposition according to prevalent management systems in the Lake Victoria zone of Tanzania, Preventive Veterinary Medicine, 26, 341-346CrossRefGoogle Scholar
- Jori, F., Mokospasetso, M., Etter, E., Munstermann, S., Newman, S.H. and Michel, A., 2013. Preliminary assessment of bovine tuberculosis at the livestock/wildlife interface in two protected areas of northern Botswana, Transboundary and Emerging Diseases, 60, 28-36. doi: 10.1111/tbed.12110.PubMedCrossRefGoogle Scholar
- Katale, B.Z., Mbugi, E.V., Karimuribo, E.D., Keyyu, J.D., Kendall, S., Kibiki, G.S., Godfrey-Faussett, P., Michel, A.L., Kazwala, R.R., van Helden, P. and Matee, M.I., 2013. Prevalence and risk factors for infection of bovine tuberculosis in indigenous cattle in the Serengeti ecosystem, Tanzania, BMC Veterinary Research, 9, doi: 10.1186/1746-6148-9-267 Google Scholar
- Mfinanga, S.G., Morkve, O., Kazwala, R.R., Cleaveland, S., Sharp, J.M., Shirima, G. and Nilsen, R., 2003. The role of livestock keeping in tuberculosis trends in Arusha, Tanzania, International Journal of Tuberculosis and Lung Disease, 7, 695-704Google Scholar
- Motsi, T.R., Tichiwangana, S.C., Matope, G. and Mukarati, N.L., 2013. A serological survey of brucellosis in wild ungulate species from five game parks in Zimbabwe, Onderstepoort Journal of Veterinary Research, 80, doi: 10.4102/ojvr.v80i1.586.
- Muma, J., Samui, K., Siamudaala, V., Oloya, J., Matope, G., Omer, M., Munyeme, M., Mubita, C. and Skjerve, E., 2006. Prevalence of antibodies to Brucella spp. and individual risk factors of infection in traditional cattle, goats and sheep reared in livestock–wildlife interface areas of Zambia, Tropical Animal Health and Production, 38, 195-206PubMedCrossRefGoogle Scholar
- Munyeme, M., Muma, J., Samui, K., Skjerve, E., Nambota, A., Phiri, I., Rigouts, L. and Tryland, M., 2009. Prevalence of bovine tuberculosis and animal level risk factors for indigenous cattle under different grazing strategies in the livestock/wildlife interface areas of Zambia, Tropical Animal Health and Production, 41, 345-352PubMedCrossRefGoogle Scholar
- Mwakapuja, R.S., Makondo, Z.E., Malakalinga, J., Bryssinckx, W., Mdegela, R.H., Moser, I., Kazwala, R.R. and Tanner, M., 2013. Prevalence and significant geospatial clusters of bovine tuberculosis infection at livestock-wildlife interface ecosystem in Eastern Tanzania, Tropical Animal Health and Production, 45, 1223-30PubMedCrossRefGoogle Scholar
- Swai, E.S. and Schoonman, L., 2010. The use of rose bengal plate test to asses cattle exposure to Brucella infection in traditional and smallholder dairy production systems of Tanga region of Tanzania, Veterinary Medicine International 2010. doi: 10.4061/2010/837950