The heptavalent pneumococcal conjugate vaccine (PCV7) targets seven of the more than 92 pneumococcal serotypes. Concerns have been raised that non-vaccine serotypes (NVTs) could increase in prevalence and reduce the benefits of vaccination. Indeed, among asymptomatic carriers, the prevalence of NVTs has increased substantially, and consequently, there has been little or no net change in the bacterial carriage prevalence.