The Contribution of Specific Pneumococcal Serogroups to Different Disease Manifestations: Implications for Conjugate Vaccine Formulation and Use, Part II

Abstract

To assess whether certain serogroups of Streptococcus pneumoniae are preferentially associated with specific disease manifestations, we analyzed all recent pneumococcal disease studies and assessed the relative frequency of isolation of each serogroup by clinical site (as a proxy for different disease states). In all age groups, serogroups 1 and 14 were more often isolated from blood, and serogroups 6, 10, and 23 were more often isolated from cerebrospinal fluid (CSF); in young children, serogroups 3, 19, and 23 were more often isolated from middle ear fluid (MEF). Serogroups represented in conjugate vaccines were isolated slightly less frequently from CSF than from blood or MEF. Nonetheless, serogroups in the 9-valent conjugate vaccine formulation still comprised approximately 75% of pneumococcal isolates from the CSF of young children in Europe and in the United States and Canada. These analyses indicate that pneumococcal conjugate vaccines could potentially prevent a substantial proportion of episodes of bacteremic disease, pneumonia, meningitis, and otitis media, especially in young children.

Invasive Pneumococcal Infection in a Healthy Infant Caused by Two Different Serotypes

“…Although any pneumococcal serotype may invade a sterile site, some serotypes seem to prefer particular locations. For instance, serotypes 1, 3, 5, 6A or 6B, 9V, 14, 19F, and 23F have been associated with invasive infections (2,4,6). In our patient, finding serotype 23B in the CSF was unusual, since it is rarely found among S. pneumoniae strains causing invasive infections.…”

“…In our patient, finding serotype 23B in the CSF was unusual, since it is rarely found among S. pneumoniae strains causing invasive infections. In the study by Hausdorff and colleagues, serotype 23B was seldom found among serotypes that cause meningitis in Latin America (6). Similarly, in the analysis of 3,066 S. pneumoniae isolates from CSF derived from the Brazilian pneumococcal surveillance system, serotype 23B was identified in only 1% of isolates (2).…”

Current status and future directions of invasive pneumococcal diseases and prophylactic approaches to control them

“…On average, there are 4,100 cases of meningitis, 8 12,000 of bacteremia, 9 500,000 of pneumonia, and 7 million cases of otitis media annually in the United States. 10 , 11 The bacterium most commonly affects pediatric, elderly, and immunocompromised hosts. S. pneumoniae is the leading cause of pneumonia in children worldwide and is responsible for 30% of adult pneumonia cases.…”

“…13,14 An average of 1.2 million young children worldwide die due to pneumococcal pneumonia and meningitis. 10 In developed countries, the mortality rate for pneumococcal pneumonia can reach 11–40%. 12 …”

Meeting the challenge: prevention of pneumococcal disease with conjugate vaccines

“…To optimize the formulation of conjugate vaccines and to evaluate the appropriateness of their use in various geographic areas and age groups, it was necessary first to understand the serogroup-specific epidemiology of S. pneumoniae. 100 Considering the large number of epidemiologic studies about pneumococcal serotype distribution worldwide, Hausdorff and colleagues performed several data analyses designed to reveal which pneumococcal serotypes should be included in conjugate vaccines. 101 The investigators analyzed more than 70 data sets to compare the serogroups causing IPD with those represented in conjugate formulations.…”