Changes in capsule and drug resistance of pneumococci after introduction of PCV7, Japan, 2010-2013

Naoko Chiba, Miyuki Morozumi, Michi Shouji, Takeaki Wajima, Satoshi Iwata, Kimiko Ubukata

Research output: Contribution to journalArticlepeer-review

88 Citations (Scopus)


We aimed to clarify changes in serotypes and genotypes mediating β-lactam and macrolide resistance in Streptococcus pneumoniae isolates from Japanese children who had invasive pneumococcal disease (IPD) after the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced into Japan; 341 participating general hospitals conducted IPD surveillance during April 2010-March 2013. A total of 300 pneumococcal isolates were collected in 2010, 146 in 2011, and 156 in 2012. The proportion of vaccine serotypes in infectious isolates decreased from 73.3% to 54.8% to 14.7% during the 3 years. Among vaccine serotype strains, genotypic penicillin-resistant S. pneumoniae strains also declined each year. Among nonvaccine serotype strains, 19A, 15A, 15B, 15C, and 24 increased in 2012. Increases were noted especially in genotypic penicillin-resistant S. pneumoniae isolates of serotypes 15A and 35B, as well as macrolide resistance mediated by the erm(B) gene in 15A, 15B, 15C, and 24.

Original languageEnglish
Pages (from-to)1132-1139
Number of pages8
JournalEmerging Infectious Diseases
Issue number7
Publication statusPublished - 2014 Jul
Externally publishedYes

ASJC Scopus subject areas

  • Epidemiology
  • Microbiology (medical)
  • Infectious Diseases


Dive into the research topics of 'Changes in capsule and drug resistance of pneumococci after introduction of PCV7, Japan, 2010-2013'. Together they form a unique fingerprint.

Cite this