Risk-based bovine brucellosis surveillance and control: assessment of outbreak, vaccination, and cattle movement in Minas Gerais

Abstract

Brucellosis is a disease of great burden for livestock and human health worldwide, affecting especially developing countries. In Brazil, the Programa Nacional de Controle e Erradicação de Tuberculose e Brucelose (PNCEBT) is responsible for regulate the control and eradication measures of the disease, since 2001. Among the Brazilian states, Minas Gerais is one of the most important considering cattle production, with bovine brucellosis still prevalent, although, the prevalence is decreasing. In this sense, the aim of this thesis was to review the occurrence of livestock brucellosis and the interface with human occurrence worldwide, combined with the development of spatiotemporal and network analysis as tools to improve the control of bovine brucellosis in Minas Gerais, Brazil. For that, it was conducted a literature review about the occurrence of livestock brucellosis worldwide, followed by a spatiotemporal analysis of bovine brucellosis cases, testing, vaccination, and bovine population size in Minas Gerais, Brazil. Additionally, a network analysis was performed with cattle movement data, also in Minas Gerais, Brazil. The results of this thesis showed the importance of livestock brucellosis in all countries where the disease is endemic, especially in countries where there were no control programs. The spatiotemporal analysis demonstrated the great achievements of the PNCEBT in the state and elucidates regions where the control measures were not well implemented. Complementarily, the network analysis showed the formation of three big communities that follow similar patterns of bovine movement in each analyzed years, suggesting the need for different control strategies in each community when considering cattle movement. In conclusion, this thesis apprises the knowledge on the occurrence of livestock brucellosis worldwide and showed alternatives analytical tools to access the control measures for bovine brucellosis, in Minas Gerais, Brazil.