Nationwide Trends of Invasive Pneumococcal Disease in Spain From 2009 Through 2019 in Children and Adults During the Pneumococcal Conjugate Vaccine Era.

Background: Introduction of pneumococcal conjugate vaccines (PCVs) has reduced the disease caused by vaccine serotypes in children, providing herd protection to adults. However, the emergence of nonvaccine serotypes is of great concern worldwide.

Methods: This study includes national laboratory data from invasive pneumococcal disease (IPD) cases that affected pediatric and adult populations during 2009-2019.

Decrease of invasive pneumococcal disease (IPD) in adults after introduction of pneumococcal 13-valent conjugate vaccine in Spain.

A prospective laboratory-based multicenter study that collected all adult invasive pneumococcal disease (IPD) episodes from 6 Spanish hospitals before (2008-2009) and after (2012-2013). The 13-valent pneumococcal conjugate vaccine (PCV13) licensure was conducted in order to analyze the impact of PCV13 introduction for children on adult IPD. A total of 1558 IPD episodes were detected.

Immunization with LytB protein of Streptococcus pneumoniae activates complement-mediated phagocytosis and induces protection against pneumonia and sepsis.

The cell wall glucosaminidase LytB of Streptococcus pneumoniae is a surface exposed protein involved in daughter cell separation, biofilm formation and contributes to different aspects of the pathogenesis process. In this study we have characterized the antibody responses after immunization of mice with LytB in the presence of alhydrogel as an adjuvant. Enzyme-linked immunosorbent assays measuring different subclasses of immunoglobulin G, demonstrated that the antibody responses to LytB were predominantly IgG1 and IgG2b, followed by IgG3 and IgG2a subclasses.

Emergence of Amoxicillin-Resistant Variants of Spain9V-ST156 Pneumococci Expressing Serotype 11A Correlates with Their Ability to Evade the Host Immune Response.

Capsular switching allows pre-existing clones of Streptococcus pneumoniae expressing vaccine serotypes to escape the vaccine-induced immunity by acquisition of capsular genes from pneumococci of a non-vaccine serotype. Here, we have analysed the clonal composition of 492 clinical isolates of serotype 11A causing invasive disease in Spain (2000-2012), and their ability to evade the host immune response. Antibiograms, serotyping and molecular typing were performed.