The study design and analysis controlled for influence of potentially confounding trends, such as improvement of day-care carriage and decreasing prevalence of smoking during the study period.
The study compares the incidence and serotype distribution of invasive pneumococcal disease (IPD) for pneumococcal meningitis and non-meningitis IPD in children from 2007 to 2010 with reference to the pre-vaccination period from 1997 to 2001 in Germany.
This study demonstrates that PCV13 is immunogenic and safe in children previously vaccinated with PCV7. By eliciting high antibacterial immune responses to the additional serotypes, PCV13 provides protection against these serotypes, which are important causes of pneumococcal disease globally.
The evidence presented in the article strongly supports the notion that serotype replacement has occurred in invasive pneumococcal disease in most populations and is caused by the vaccine.
Universal screening of pregnant women is feasible and has led to immunisation in nearly all identified cases in Denmark. As a consequence of the study the National Board of Health has made universal HBsAg screening of pregnant women permanent in the country.
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.