[Contribution of mathematical modeling to vaccination decision making. Examples from varicella, rotavirus and papillomavirus vaccinations].

The decision to add a new vaccine to the immunization schedule is a complex and multidisciplinary process based on the risk-benefit balance and, increasingly, on the cost- effectiveness ratio. Such decisions now use mathematical models that can predict the indirect, and potentially detrimental, effects of mass vaccination on the epidemiology of the target disease. The adjunction of an economic component to the modeling process ensures that vaccination represents an efficient allocation of available financial resources in an increasingly constrained environment.