On 18 April 2018, Venetia Karamitsou, PhD student in the Disease Dynamics group at the University of Cambridge, held a talk at SACEMA on modelling the evolution of influence. Given that vaccination is the main control strategy against influenza outbreaks, it is worrisome that influenza mutates often, making reinfection possible even for vaccinated individuals. Existing models regarding the evolution of influenza focus on either changes within hosts or between hosts. The main motivation behind the current research is to find out how both types of models can be combined. The results from the study can be useful in reassessing vaccination policies.