Serotype replacement in disease after pneumococcal vaccinationArchived
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.
Weinberger D, Malley R, Lipsitch M. The Lancet - 13 April 2011 DOI: 10.1016/S0140-6736(10)62225-8
In many populations, pneumococcal disease caused by NVT has increased, but in most cases this increase has been less than the increase in NVT carriage. In this review, the authors discuss the evidence for serotype replacement in carriage and disease, and address the surveillance biases that might affect these findings. They then discuss possible reasons for the discrepancy between near-complete replacement in carriage and partial replacement for disease, including differences in invasiveness between vaccine serotypes. The authors contend that the magnitude of serotype replacement in disease can be attributed, in part, to a combination of lower invasiveness of the replacing serotypes, biases in the pre-vaccine carriage data (unmasking), and biases in the disease surveillance systems that could underestimate the true amount of replacement. They conclude by discussing the future potential for serotype replacement in disease and the need for continuing surveillance.
Decline in early childhood respiratory tract infections in the norwegian mother and child cohort study after introduction of pneumococcal conjugate vaccinationArchived
27 Nov 2012 - 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.
A review of the effect of immunization programs on antimicrobial utilizationArchived
16 Oct 2012 - Antimicrobial stewardship policies are increasingly being implemented as a measure to prevent and control antimicrobial resistance.
Four years of universal pneumococcal conjugate infant vaccination in Germany: Impact on incidence of invasive pneumococcal disease and serotype distribution in childrenArchived
16 Aug 2012 - 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.