title: Changes in nasopharyngeal carriage of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis among healthy children attending a day-care centre before and after official financial support for the 7-valent pneumococcal conjugate vaccine and H. influenzae type b vaccine in Japan.
abstract: The 7-valent pneumococcal conjugate vaccine (PCV7) and Haemophilus influenzae type b (Hib) vaccine reduce nasopharyngeal carriage of vaccine-type bacteria, which may in turn influence the presence of other nasopharyngeal bacterial pathogens. To investigate this possibility, nasopharyngeal carriage of potential pathogens was examined before and after official financial support was provided to offer the PCV7 and Hib vaccines in healthy children attending a day care centre in Japan during 2011-2012. Despite a virtual disappearance of PCV7 serotypes over time, the overall pneumococcal carriage rate remained unchanged. Although others have reported an increase in PCV13 serotypes following PCV7 vaccination, only non-PCV13 serotypes were observed to have increased in this study. The majority of H. influenzae isolates were non-typeable and Hib was not found. Our data identified an unexpected pattern of pneumococcal serotype replacement following PCV7. Continuous monitoring of pneumococcal carriage is important for decisions regarding the future of national vaccination policy in Japan.
authors.affiliation: Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan. Electronic address: oikawa@chiba-u.jp.
authors.forename: Junko
authors.initials: J
authors.lastname: Oikawa
authors.affiliation: Division of Control and Treatment of Infectious Diseases, Chiba University Hospital, Chiba, Japan.
authors.forename: Naruhiko
authors.initials: N
authors.lastname: Ishiwada
authors.affiliation: Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Hishiki
authors.affiliation: Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Koo
authors.initials: K
authors.lastname: Nagasawa
authors.affiliation: Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Takahashi
authors.affiliation: Division of Laboratory Medicine, Chiba University Hospital, Chiba, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Bacteriology Ⅰ, National Institute of Infection Diseases, Tokyo, Japan.
authors.forename: Bin
authors.initials: B
authors.lastname: Chang
authors.affiliation: Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Kohno
mesh_terms: D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology*; D002648:Child; D002656:Child Day Care Centers; D002675:Child, Preschool; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000191:economics; D006193:Haemophilus influenzae / Q000302:isolation & purification*; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008297:Male; D001936:Moraxella catarrhalis / Q000302:isolation & purification; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000382:microbiology; D022242:Pneumococcal Vaccines / Q000008:administration & dosage* / Q000191:economics; D013296:Streptococcus pneumoniae / Q000302:isolation & purification*
chemical_list: D018073:Haemophilus Vaccines; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022242:Pneumococcal Vaccines
keywords: 7-Valent pneumococcal conjugate vaccine; Haemophilus influenzae; Hib vaccine; Nasopharyngeal carriage; Streptococcus pneumoniae