Specific scientific and technological objectives

• To identify factors affecting the observed rates of invasive pneumococcal (Pnc) disease and to estimate the actual incidence of invasive Pnc disease.
• To develop novel methodologies to measure and interpret natural Pnc immunity and to apply these methods to sera from a variety of pre-vaccination populations.
• To determine the incidence, prevalence and transmission patterns of Pnc upper respiratory carriage for different serotypes and antibiotic resistant strains in two geographical areas.
• To develop mathematical models of transmission of Pnc carriage and incidence of invasive Pnc disease to evaluate alternative vaccination programmes in the participating countries.
• To calculate the economic burden of invasive Pnc disease and to determine the cost-effectiveness of different vaccination strategies.