RESUMEN
A prospective, randomised, controlled observer-blind trial measuring the efficacy and immunogenicity of trivalent influenza vaccine (TIV) and the immunogenicity of quadrivalent meningococcal conjugate vaccine (MCV) in pregnant women and their infants up to 6â¯months of age was conducted in Mali. Here we reported the immunogenicity of MCV, which was used as a comparator vaccine to TIV, in this population. Third-trimester pregnant Malian women were randomized to receive TIV or MCV. Blood samples were collected from women prior to vaccination, 28â¯days post-vaccination, at delivery and 3 and 6â¯months post-delivery and from infants at birth and 3 and 6â¯months of age. Meningococcal-specific serogroup (Men) A, C, Y and W-specific antibodies were measured by enzyme linked immunosorbent assay in a randomly selected subset of 50 mother-infant pairs where the mother had received MCV. At birth, 94.0% (47/50) of infants had MenA specific IgG levelsâ¯≥â¯2⯵g/mL decreasing to 72.9% and 30.4% at 3 and 6â¯months of age. For MenC, 81.3% (39/48) of infants had MenC specific IgG levelsâ¯≥â¯2⯵g/mL at birth decreasing to 29.4% and 17.8% at 3 and 6â¯months of age. For MenY, 89.6% (43/48) of infants had MenY specific IgG levelsâ¯≥â¯2⯵g/mL at birth decreasing to 64.6% and 62.5% at 3 and 6â¯months of age. For MenW, 89.6% (43/48) of infants had MenW specific IgG levelsâ¯≥â¯2⯵g/ml at birth decreasing to 62.5% and 41.7% at 3 and 6â¯months of age. Maternal immunization with MCV conveyed protective levels of IgG at birth through to 3â¯months of age in the majority of infants.