Modeling the transmission dynamics of sheep brucellosis in Inner Mongolia Autonomous Region, China.

Brucellosis is one of the major zoonotic diseases in China, especially in Inner Mongolia where occurs the largest number of human brucellosis cases of Mainland China, which can be attributed to the large number of sheep kept there, since at least 90% of the human brucellosis cases are caused by sheep. Therefore, given the characteristics of the brucellosis infection in Inner Mongolia Autonomous Region, we propose a dynamic model for the sheep-human transmission of brucellosis, involving sheep population, human population and brucella in the environment. We first determine the basic reproduction number R(0) and analyze the global stability of the disease-free and endemic equilibrium. Secondly, using the reported human brucellosis data, we carry out numerical simulations and make sensitivity analysis of the basic reproduction number in terms of some parameters. The results show that brucellosis cannot be eradicated even though disinfection rate and vaccination rate of adult sheep are 100%. By investigating and comparing the effect of vaccination, disinfection and eliminating strategies, we find that vaccinating and disinfecting both young and adult sheep are appropriate and effective strategies to control brucellosis in Inner Mongolia of China.