Novel strains emerge every year and cause seasonal flu epidemic. These variants exhibit differences in antigenicity and may escape immunity from vaccines and thus invade the population. Here, we devise a discrete population game model of vaccination and transmission of two strains – a resident and a relatively rare mutant – to explain the influence of social behaviour, specifically vaccinating behaviour on the emergence of the mutant strain in the population. Our integrated framework of behaviour-prevalence model exhibits time evolution of two strategic interactions such as individuals' perceived vaccination risk and probability of infection, where both declines as more and more individuals vaccinate in the population. Numerical simulation and analysis of the model show that the predominant Nash strategy allows invasion of the mutant strain under very disparate individuals perceived disease risks from these two pathogens and relatively lower vaccine efficacy against the mutant. The model also demonstrates that invasion of the mutant has a nonlinear dependence on epidemiological characteristics such as the relative force of infection, cross-immunity, perceived cost of treatment and vaccine efficacy. This study exemplifies that adaptive social behaviour is an important component of public health strategic decision-making during the control of the flu-like epidemic.

每年都会出现新的菌株并导致季节性流感流行。这些变体表现出抗原性差异，可能会逃避疫苗的免疫力，从而入侵人群。在这里，我们设计了一种疫苗接种和两种菌株传播的离散种群博弈模型——一种常驻菌株和一种相对稀有的突变体——来解释社会行为的影响，特别是疫苗接种行为对种群中突变菌株出现的影响。我们的行为流行率模型的综合框架展示了两个战略相互作用的时间演变，例如个人感知的疫苗接种风险和感染概率，随着人口中越来越多的人接种疫苗，两者都会下降。该模型的数值模拟和分析表明，主要的 Nash 策略允许在非常不同的个体感知来自这两种病原体的疾病风险和相对较低的疫苗针对突变体的效力下入侵突变株。该模型还表明，突变体的入侵对流行病学特征具有非线性依赖性，例如感染的相对强度、交叉免疫、治疗的感知成本和疫苗效力。本研究表明，在控制流感样流行期间，适应性社会行为是公共卫生战略决策的重要组成部分。该模型还表明，突变体的入侵对流行病学特征具有非线性依赖性，例如感染的相对强度、交叉免疫、治疗的感知成本和疫苗效力。本研究表明，在控制流感样流行期间，适应性社会行为是公共卫生战略决策的重要组成部分。该模型还表明，突变体的入侵对流行病学特征具有非线性依赖性，例如感染的相对强度、交叉免疫、治疗的感知成本和疫苗效力。本研究表明，在控制流感样流行期间，适应性社会行为是公共卫生战略决策的重要组成部分。