Abstract
Streptococcus pneumoniae serotypes are changing due to the widely introduced pneumococcal conjugate vaccines. Surveillance studies have proven valuable in monitoring these vaccine effects. S. pneumoniae is highly adaptable to its human reservoir and colonises mucosal surfaces of upper airways mainly in children. Carriage decreases during the first 2 years of life because of the development of naturally acquired adaptive immune memory. Most of the serotypes do not cause serious illnesses but few of them are responsible for severe pneumococcal infections. Ten of the most common serotypes are estimated to cause over 60% of invasive diseases worldwide. The virulence factor of S. pneumoniae is the polysaccharide capsule as non-encapsulated strains are absent among the strains causing invasive pneumococcal disease. Prevalence of serotypes differs depending on the age group and geographic area of patients. Differences in PCV implementation lead to changes in serotype distribution and to significant reduction of disease caused by vaccine types.
Publisher
National Center of Infectious and Parasitic Diseases
Subject
Infectious Diseases,Microbiology (medical),General Immunology and Microbiology
Reference15 articles.
1. The Evidence Base for Pneumococcal Conjugate Vaccines (PCVs): Data for decision-making around PCV use in childhood. Johns Hopkins Bloomberg School of Public Health, January 2017. Available from: https://www.jhsph.edu/ivac/wp-content/uploads/2018/05/PCVEvidenceBase-Jan2017.pdf
2. Ndlangisa K, du Plessis M, Allam M, Wolter N, de Gouveia L, Klugman KP, Cohen C, Gladstone RA, von Gottberg A. Invasive disease caused simultaneously by dual serotypes of Streptococcus pneumoniae. J Clin Microbiol. 2018; 56:e01149-17.
3. Weiser J, Ferreira D, Paton J. Streptococcus pneumoniae: transmission, colonization and invasion. Nat Rev Microbiol.2018; 16:355–367.
4. CDC - Immunology and Vaccine-Preventable Diseases – Pink Book – Pneumococcal Disease. Available from: https://www.cdc.gov/vaccines/pubs/pinkbook/pneumo.html
5. Simell B, Auranen K, Käyhty H, Goldblatt D, Dagan R, L O’Brien K. The fundamental link between pneumococcal carriage and disease. Expert Rev Vaccines. 2012; 11(7):841-855.