Objectives - The recent availability of varicella vaccines, either as monovalent vaccines or in combination with vaccines against measles, rubella, and mumps, has led the Technical Committee on Immunization to examine the appropriateness of vaccinating infants. Methods - The analysis was based on the characteristics of the vaccine and available epidemiological data on chickenpox. A mathematical model of the impact of vaccination, taking into account its direct and indirect effects for different levels of vaccination coverage, was developed. Results - Despite the epidemiological burden of chickenpox due to its very high prevalence, the vaccine’s satisfactory safety profile, and the likely economic benefit of infant vaccination, the risk-benefit balance of such a strategy was deemed unfavorable. The main reason for this was the risk of an increase in the incidence of cases among adults, linked to insufficient duration of protection and vaccination coverage. Discussion - The chosen vaccination strategy consisted of targeted vaccination of individuals of all ages at risk of severe chickenpox or at risk of transmitting the virus to such individuals. This analysis illustrates the difficulty of the vaccination decision. It highlights the need to use models that take into account, beyond the individual benefits associated with protecting vaccinated individuals,