Recent advances in the epidemiology and prevention of Streptococcus pneumoniae infections

Abstract

The introduction of pneumococcal conjugate vaccines (PCVs) 7 and 13 into national childhood immunization programs in the US in 2000 and 2010, respectively, proved to be remarkably successful in reducing infant mortality due to invasive pneumococcal disease (IPD), resulting in widespread uptake of these vaccines. Secondary herd protection of non-vaccinated adults against IPD has proven to be an additional public health benefit of childhood immunization with PCVs, particularly in the case of the vulnerable elderly who are at increased risk due to immunosenescence and underlying comorbidity. Despite these advances in pneumococcal immunization, the global burden of pneumococcal disease, albeit of unequal geographic distribution, remains high. Reasons for this include restricted access of children living in many developing countries to PCVs, the emergence of infection due to non-vaccine serotypes of the pneumococcus, and non-encapsulated strains of the pathogen. Emerging concerns affecting the elderly include the realization that herd protection conferred by the current generation of PCVs (PCV7, PCV10, and PCV13) has reached a ceiling in many countries at a time of global population aging, compounded by uncertainty surrounding those immunization strategies that induce optimum immunogenicity and protection against IPD in the elderly. All of the aforementioned issues, together with a consideration of pipeline and pending strategies to improve access to, and serotype coverage of, PCVs, are the focus areas of this review.

Induction of Krüppel-Like Factor 4 Mediates Polymorphonuclear Neutrophil Activation in Streptococcus pneumoniae Infection

“…The emergence of multidrug-resistant S. pneumoniae strains has increased the mortality and morbidity associated with pneumococcal infections ( Van Bambeke et al, 2007 ). Available pneumococcal vaccines such as the polysaccharide vaccine or the pneumococcal conjugate vaccine provide insufficient immunization ( Feldman and Anderson, 2020 ). Taken together, S. pneumoniae is responsible for approximately 40,000 deaths per year in the United States alone ( Brooks and Mias, 2018 ).…”

Invasive pneumococcal disease burden in hospitalized adults in Bogota, Colombia

“…The PPSV23 includes 23 serotypes of pneumococci polysaccharides, which stimulate the immune system to produce antibodies [ 15 ]. Unconjugated polysaccharide vaccines induce a T‐cell response, without the establishment of B‐cell memory while conjugated polysaccharide vaccines as well as inducing T-cell response also establish B-cell memory that ensures long- term immunization effect [ 16 – 19 ]. Different studies have shown that more than 80% of healthy adults who receive PPSV23 develop antibodies against the serotypes contained in the vaccine; the immune response usually occurs within 2 to 3 weeks after vaccination in adults.…”

Management and Outcomes of Paediatric Intracranial Suppurations in Low- and Middle-Income Countries: A Scoping Review

“…As of 2016, 59 countries did not have the pneumococcal vaccine in their childhood immunisation schemes. Access to vaccines in most LMICs has been limited by cost but this challenge has been addressed by GAVI, the Vaccine Alliance which has sponsored the pneumococcal vaccine in 54 countries (21,22). Given otitis has been identified to be the most prevalent predisposing factor to intracranial suppurations across LMICs, it may also be possible to reduce intracranial suppurations by promptly treating otitis with effective antibiotics.…”