Optimal Antibiotic Usage Policy Considering Fitness Cost And Drug Resistance Factors

Antibiotic resistance has become a serious problem in modem medicine.There still exists severe abuse of antibiotics today for a variety of reasons.On the one hand,patients’ irrational decisions when receiving antibiotic treatment often lead to the de-viation of the actual demand for antibiotics from the optimal social input.On the other hand,the complexity of drug resistance is greatly increased by the changeable context of specific decisions.From the static and dynamic perspectives,our study were based on the dynamic evolution model of infectious diseases and economic model,combining resistance fac-tor,the fitness cost,resistance cost,patients behavior,and the market structure of phar-maceutical manufacturers,etc.The nonlinear constraint optimization method and the optimal control theory were applied to explore the reasonable antibiotic use strategy.The research content and results are mainly reflected in the following aspects:Firstly,endogenous resistance and cross resistance were considered.The result showed that the over-dependence on one of the antibiotics can be alleviated to a certain extent by considering the cross-resistance of antibiotics,thus prolonging the service life of antibiotics.Secondly,the fitness cost of bacteria was considered.It was found that if the fitness cost is greater than 0,the rational control of antibiotic dosage can reduce the generation of bacterial resistance,maintaining the efficacy of antibiotics for a long time,and the loss of social welfare is smaller at this case.Finally,the cost ofdrug resistance of patients was considered.The study found that:(1)under the condition of maximization of manufacturer’s profit and social welfare,the effectiveness of antibiotics is different,and the relationship between the two depends on the production cost of antibiotics,the overall level of drug resistance of pathogenic strains,and the cost of drug resistance caused by the use of antibiotics.(2)when the marginal treatment cost of antibiotics is greater than 0,the government can use the tax policy to guide manufacturers’,production behavior so as to increase social welfare,while if the marginal treatment cost of antibiotics is less than 0,subsidy policy could be adopted.