Modeling And Research Of Brucellosis With Environment Factor

Brucellosis is a highly infectious zoonotic disease caused by brucellosis.Because it is not transmitted from person to person,it is mainly transmitted by sheep,cattle,dogs and other animals.In recent years,because of the increase of livestock trade,the spread of brucellosis has led to outbreaks in many provinces and cities.It not only threatens people’s safety,but also causes serious economic losses.The theoretical study of propagation dynamics system is an important quantitative research method.It enables people to understand the global transmission of diseases and disease prediction.This has certain theoretical and practical significance to the prevention and treatment of diseases.The main work of this paper is summarized as follows:In the first part,we studied a brucellosis family with environmental factors and canine-sheep cross infection.Firstly,the basic regeneration number of the system is given and its stability is proved.Obtain the local stability of the endemic equilibrium point whenR₀>1,and the consistent persistence of the disease.Numerical simulation was conducted based on the reported data of the number of brucellosis cases in Xinjiang from 2010 to 2015.Finally,sensitivity analysis of the parameters showed that strict control and vaccination in the contact route of dog-sheep population could effectively reduce the number of human cases.In the second part,based on the direct infection of infected cattle and sheep to human and the indirect infection of environmental factors to human,a classSIRWS_s I_s R_s S_c I_c system is established.The threshold values of the system are given,and the global stability of the disease-free equilibrium atR₀<1 and the consistent persistence of the endemic equilibrium atR₀>1 are proved.Based on the reported data of brucellosis cases in Inner Mongolia from 2016 to 2018,the numerical simulation was carried out and the development trend was predicted.Finally,sensitivity analysis of different parameters showed that isolated feeding of cattle and sheep and environmental elimination could reduce the number of cases to a certain extent.In the third part,a randomS₁ S₂ IVW brucellosis system is proposed by introducing environmental white noise into deterministic system.Firstly,the global existence,uniqueness and boundedness of positive solutions for stochastic systems are proved by using pause theory.Secondly,sufficient conditions for disease extinction were established.The stationary distribution and ergodic properties of the system are obtained by constructing Lyapunov function.Finally,numerical simulation is used to verify the rationality of the conclusion.