A Multivalent Conjugate Vaccinefor PreventionofMeningococcal Diseasein Infants

摘要

MAJOR PROGRESS HAS BEEN MADE IN THE DEVEL-opment of meningococcal vaccines in the past few years. Monovalent serogroup C conjugate vaccines, shown to be immunogenic and effective in infants, have dramatically decreased the incidence of serogroup C disease in the countries in which they have been used.1"4 This reduction has occurred among those immunized and, through a decrease in pharyngeal carriage of serogroup C Neisseria meningitidis, also among the un-immunized population.5'6 These vaccines do not cover serogroup Y strains, an important cause of meningococcal disease across all age groups in the United States, including infants, and are not licensed in the United States. A new tet-ravalent (serogroups A, C, W-135, and Y) conjugate vaccine licensed for 2- to 55-year-olds is now recommended for all US adolescents, as well as other high-risk groups.7 This recommendation was based on the fact that US adolescents were found to have both a relatively high incidence of meningococcal disease and a high case fatality rate.78 Unlike monovalent serogroup C vaccines, the currently licensed tetravalent conjugate vaccine was judged to be insufficiently immunogenic in infants, the group with the highest risk of meningococcal disease.9 An analysis conducted by Lingappa et al10 indicated that a combined approach of immunizing infants and adolescents and college students would have the largest effect in terms of number of cases and deaths prevented. It is clear that the current focus on adolescents in die United States is an interim measure; a multivalent vaccine for infants is also needed