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

• Published in: Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy Vol. 20; no. 2; pp. 146 - 149
• Main Authors: Oikawa, Junko, Ishiwada, Naruhiko, Takahashi, Yoshiko, Hishiki, Haruka, Nagasawa, Koo, Takahashi, Sachiko, Watanabe, Masaharu, Chang, Bin, Kohno, Yoichi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.02.2014
• Subjects: 7-Valent pneumococcal conjugate vaccine; Carrier State - epidemiology; Carrier State - microbiology; Child; Child Day Care Centers; Child, Preschool; Female; Gram-Negative Bacterial Infections - epidemiology; Gram-Negative Bacterial Infections - microbiology; Haemophilus influenzae; Haemophilus influenzae - isolation & purification; Haemophilus Vaccines - administration & dosage; Haemophilus Vaccines - economics; Hematology, Oncology and Palliative Medicine; Heptavalent Pneumococcal Conjugate Vaccine; Hib vaccine; Humans; Infant; Japan - epidemiology; Male; Moraxella (Branhamella) catarrhalis - isolation & purification; Nasopharyngeal carriage; Nasopharynx - microbiology; Pneumococcal Infections - epidemiology; Pneumococcal Infections - microbiology; Pneumococcal Vaccines - administration & dosage; Pneumococcal Vaccines - economics; Streptococcus pneumoniae; Streptococcus pneumoniae - isolation & purification; Japan; 7-Valent pneumococcal conjugate vaccine; Nasopharyngeal carriage; Hib vaccine; Haemophilus influenzae; Streptococcus pneumoniae
• ISSN: 1341-321X; 1437-7780
• DOI: 10.1016/j.jiac.2013.10.007

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.