Background. In 2002 the Advisory Committee on Immunization Practices (ACIP) began encouraging annual influenza vaccination of children 6 to 23 months of age, when feasible.
Methods. Literature and issues related to annual influenza vaccination of young children were reviewed.
Results. The ACIP first encouraged influenza vaccination of children 6 to 23 months of age in 2002 because recent studies showed that influenza-related hospital admissions were substantially higher among healthy children <2 years than among healthy older children or young adults. However, the ACIP deferred a full recommendation for several reasons, including limited safety and efficacy data on trivalent inactivated influenza virus in the 6- to 23-month age group, the need for more education of parents and physicians and concerns over the stability and adequacy of the vaccine supply.
Conclusions. The risk of hospital admission from influenza-related causes is high in young children and similar to the risk in the elderly and other high risk groups for whom annual influenza vaccination is already recommended. Data from additional studies, especially those on vaccine safety and efficacy, will be important for proceeding to a full recommendation for annual influenza vaccination of children 6 to 23 months.