0000000000188350
AUTHOR
Jan Poolman
International Bordetella pertussis assay standardization and harmonization meeting report. Centers for Disease Control and Prevention, Atlanta, Georgia, United States, 19–20 July 2007
An international meeting on Bordetella pertussis assay standardization and harmonization was held at the Centers for Disease Control and Prevention (CDC), Atlanta, GA, 19-20 July 2007. The goal of the meeting was to harmonize the immunoassays used for pertussis diagnostics and vaccine evaluation, as agreed upon by academic and government researchers, regulatory authorities, vaccine manufacturers, and the World Health Organization (WHO). The primary objectives were (1) to provide epidemiologic, laboratory, and statistical background for support of global harmonization; (2) to overview the current status of global epidemiology, pathogenesis and immunology of pertussis; (3) to develop a consen…
Glycoconjugate vaccines and immune interactions, and implications for vaccination schedules.
Conjugate vaccines using diphtheria toxoid variant (CRM(197)), diphtheria toxoid and tetanus toxoid (TT) as carrier protein may induce immune interactions (interference or impairment as measured by lower antibody levels, or enhancement [higher antibody levels]) when coadministered with other vaccines. Immune enhancement occurs when two TT conjugates are coadministered. CRM(197) conjugate vaccines induce immune bystander interference when given with diphtheria-tetanus-acellular pertussis vaccines, which reduces responses to coadministered Haemophilus influenzae type b vaccine conjugated to TT. These bystander effects are greater as the amount of CRM(197) administered increases. When large am…
A dose-range study assessing immunogenicity and safety of one dose of a new candidate meningococcal serogroups A, C, W-135, Y tetanus toxoid conjugate (MenACWY-TT) vaccine administered in the second year of life and in young children.
Meningococcal disease incidence is highest in young children, yet a tetravalent conjugate vaccine is currently not available for this age group. This study evaluated a single dose of four different ACWY-TT conjugate vaccine formulations in 240 toddlers (12-14 months) and 268 children (3-5 years) compared to licensed age-appropriate control vaccines. In toddlers, rSBA-MenC GMTs for the selected formulation were statistically higher than after monovalent-MenC-conjugate vaccine. In children, rSBA-GMTs against each serogroup were statistically higher than after tetravalent polysaccharide vaccine. The safety profile was comparable to licensed controls. The new ACWY-TT conjugate vaccine promises …
Combination vaccines containing DTPa–Hib: impact of IPV and coadministration of CRM197 conjugates
Vaccination with diphtheria-tetanus-acellular pertussis (DTPa)-Haemophilus influenzae type b (Hib) combinations generally elicits anti-polyribosyl-ribitol-phosphate (PRP) antibody concentrations of more than 0.15 microg/ml, a criterion that is linked to the protection of infants against Hib disease. In the UK, vaccination with DTPa3-Hib elicited atypically low anti-PRP antibody levels and was associated with breakthrough Hib cases. While the absence of a toddler booster is considered to be a key factor explaining the lowered control of Hib disease, we propose that the coadministration of serogroup C Neisseria meningitidis conjugate vaccine (MenC)-CRM197, which coincided with the introductio…
Prediction of pneumococcal conjugate vaccine effectiveness against invasive pneumococcal disease using opsonophagocytic activity and antibody concentrations determined by enzyme-linked immunosorbent assay with 22F adsorption.
ABSTRACT We compared the abilities of two serological readouts, antipolysaccharide IgG antibody concentrations and opsonophagocytic activity (OPA) titers, to predict the clinical effectiveness of the 7-valent pneumococcal conjugate vaccine (7vCRM) against invasive pneumococcal disease (IPD). We also assessed the accuracy of the previously established thresholds for GlaxoSmithKline's enzyme-linked immunosorbent assay with 22F adsorption (22F-ELISA) (≥0.2 μg/ml) and OPA assay (titer, ≥8) in predicting effectiveness. We showed that following a 3-dose 7vCRM primary vaccination, the serological response rates as determined using thresholds of ≥0.2 μg/ml IgG and an OPA titer of ≥8 corresponded we…