Long term population impact of seven-valent pneumococcal conjugate vaccine with a "3+0 double prime schedule-How do "2+1 double prime and "3+1 double prime schedules compare?

Introduction Significant reductions in invasive pneumococcal disease (IPD) following 7-valent pneumococcal conjugate vaccine (7vPCV) are well documented, but population-level data comparing different schedules are sparse. We compared data from long-term stable surveillance in one Australian region (3 primary doses (3+0) schedule) with similar data from England and Wales (2+1 schedule) and the United States (3+1 schedule). Methods Incidence rate ratios (IRRs) for all, vaccine type, and non-vaccine type IPD were calculated by age-group, using comparable case definitions and time periods post 7vPCV introduction. Results At baseline, the % of IPD due to 7vPCV serotypes (VT) disease in children