Impact on meningococcal disease of different vaccination strategies with 4CMenB and MenACWY-CRM197 in infants and adolescents in Argentina.

Background: Invasive meningococcal disease (IMD) is a life-threatening disease, primarily affecting infants and children. Argentina introduced routine meningococcal vaccination in infants and adolescents in 2017, with MenACWY vaccination targeting serogroups A, C, W, and Y (current National Immunization Program [cNIP]). Serogroup B, more prevalent since 2015, became predominant in children.

Modeling the public health impact of different meningococcal vaccination strategies with 4CMenB and MenACWY versus the current toddler MenACWY National Immunization Program in Chile.

Invasive meningococcal disease (IMD) is an uncommon yet unpredictable, severe, and life-threatening disease with the highest burden in young children. In Chile, most IMD is caused by meningococcal serogroup B (MenB) and W (MenW) infection. In response to a MenW outbreak in 2012, a toddler vaccination program was implemented using quadrivalent meningococcal conjugate vaccine against serogroups A, C, W and Y (MenACWY).

Immunogenicity and safety of investigational vaccine formulations against meningococcal serogroups A, B, C, W, and Y in healthy adolescents.

This phase 2 study assessed the immunogenicity, safety, and reactogenicity of investigational formulations of meningococcal ABCWY vaccines, consisting of recombinant proteins (rMenB) and outer membrane vesicle (OMV) components of a licensed serogroup B vaccine, combined with components of a licensed quadrivalent meningococcal glycoconjugate vaccine (MenACWY-CRM). A total of 495 healthy adolescents were randomized to 6 groups to receive 2 doses (Months 0, 2) of one of 4 formulations of rMenB antigens, with or without OMV, combined with MenACWY-CRM, or 2 doses of rMenB alone or one dose of MenACWY-CRM then a placebo. Immunogenicity was assessed by serum bactericidal assay with human complement (hSBA) against serogroups ACWY and serogroup B test strains; solicited reactions and any adverse events (AEs) were assessed.