Invasive pneumococcal infections in Vellore, India: clinical characteristics and distribution of serotypes

Abstract

BackgroundStreptococcus pneumoniae infection is a serious problem worldwide and the case fatality rate remains high. The aim of this study was to analyze the distribution of pneumococcal serotypes causing invasive pneumococcal disease (IPD), to survey the potential coverage of present and future vaccines, and to investigate differences between serotypes and groups of serotypes with regard to manifestation, case fatality rate, age, and other risk factors.MethodsIsolates from 244 consecutive patients with IPD were collected at the Christian Medical College, Vellore, India between January 2007 and June 2011, and clinical data were obtained retrospectively. Clinical characteristics were analyzed both for individual serotypes and for those grouped as “invasive”, “pediatric”, or “vaccine” serotypes.ResultsThe serotype coverage for the pneumococcal conjugated vaccines (PCV) PCV7, PCV10, PCV13, PCV15, and pneumococcal polysaccharide vaccine (PPV) PPV23 was 29%, 53%, 64%, 66%, and 73%, respectively. The proportion of IPD caused by vaccine types was lower than pre-vaccination studies from other parts of the world. In adults, serotype 1 was mainly isolated from previously healthy patients without risk factors for IPD. This serotype caused more pneumonia and less meningitis than other serotypes, as was also noted for the “invasive” serotypes (1, 5, and 7 F).ConclusionsThe most common pneumococcal serotypes in this study behaved in similar ways to those in countries where the PCV has been introduced. Also, the most common serotypes in this study are included in the new PCVs. Therefore, a national program of childhood immunization with PCV10/13 in India is likely to be successful.

Epidemiology of Invasive Pneumococcal Disease in Bangladeshi Children Before Introduction of Pneumococcal Conjugate Vaccine

“…36 Our serotype distribution differed from that reported in the global analysis in part due to the relatively high frequency of serotypes 2, 12A, 45, 18F and 8, which are not in any of the PCV formulations. Data from Bangladesh's neighboring countries, Nepal 37,38 and India, 39 also revealed diverse serotypes. The Indian study had 55 different serotypes among 244 IPD cases and Nepal had 17 serotypes among 42 isolates.…”

Streptococcus pneumoniae serotype prevalence and antibiotic resistance among young children with invasive pneumococcal disease: experience from a tertiary care center in South India

“…4 The occurrence of nonvaccine (21.4%) serotypes (i.e., that are not included in PCV10, PCV-13 and PPV-23) is also consistent with the observations of other studies, reporting rates of 25.4% 4 and 27%. 17 The emergence of non-vaccine serotypes might presumably be a result of the introduction of recent clones or even a result of capsular switching of existing stain or by many single genetic changes. [18][19][20] This baseline information would be important in regions where the population is relatively naïve to the vaccine.…”

Impact of 10- and 13-valent pneumococcal conjugate vaccines on incidence of invasive pneumococcal disease in children aged under 16 years in Germany, 2009 to 2012

“…A literature review published in 2013, with observations from other countries, addressed the issue of tropism of different pneumococcal serotypes: serotypes 1, 19A and 3 were identified as predominant for pneumococcal pneumonia but not for meningitis IPD during the post-PCV7 period [14]. A recent paper from India, not included in the review, reported that serotypes 1, 5 and 7F (three of the six additional serotypes in PCV13) caused more pneumonia than meningitis [15].…”