Hyporesponsiveness to the infecting serotype after vaccination of children with seven-valent pneumococcal conjugate vaccine following invasive pneumococcal disease.
Antibody responses to the infecting serotype in children who are vaccinated with pneumococcal conjugate vaccine (PCV) after having invasive pneumococcal diseases (IPD) have not been fully investigated. Of 56 children diagnosed with IPD between October 2009 and April 2013 in whom the infecting serotype was confirmed, 17 who were vaccinated with PCV7 following IPD were tested to determine the geometric mean concentration of serotype-specific immunoglobulin G (IgG) and the geometric mean titers of opsonization indices (OIs) using paired sera obtained at the onset of IPD and after PCV doses following the resolution of IPD. The geometric mean concentrations of serotype-specific IgG for all PCV7 serotypes other than serotype 6B were significantly increased after the last PCV7 dose compared with those at the time of IPD onset (P<0.01), as were the geometric mean titers of OIs for all PCV7 serotypes. In 14 children with IPD caused by PCV7 serotypes for whom both IgG and OI results were available, the OIs for the infecting serotype at the time of IPD onset were <8, although the IgG levels varied between from <0.2 to >5.0μg/ml. After the last PCV7 dose, the OIs for the infecting serotype remained <8 for six (43%) of 14 children. In these six children, hyporesponsiveness to PCV7 was specific for the infecting serotype. Hyporesponsiveness was found for serotypes 6B (n=5) and 23F (n=1). No difference was found between the responders (n=8) and the hyporesponders (n=6) with regard to any clinical characteristics. Our data suggest that hyporesponsiveness to the infecting serotype may occur in children vaccinated with PCV7 following IPD.
Laboratory for Clinical Research on Infectious Disease, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; Department of Respiratory Medicine, Allergy and Rheumatic Disease, Graduate School of Medicine, Osaka University, Osaka, Japan.
Kazuyo
K
Tamura
Department of Pediatrics, Nishi-Kobe Medical Center, Kobe, Japan.
Kousaku
K
Matsubara
Division of Control and Treatment of Infectious Diseases, Chiba University Hospital, Chiba, Japan.
Naruhiko
N
Ishiwada
Department of Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Junichiro
J
Nishi
Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
Hidenori
H
Ohnishi
National Mie Hospital, Mie, Japan.
Shigeru
S
Suga
National Mie Hospital, Mie, Japan.
Toshiaki
T
Ihara
Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan.
Bin
B
Chang
Laboratory for Clinical Research on Infectious Disease, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
Yukihiro
Y
Akeda
Laboratory for Clinical Research on Infectious Disease, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; Infectious Disease Surveillance Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjyuku, Tokyo 162-8640, Japan. Electronic address: oishik@nih.go.jp.
Kazunori
K
Oishi
D000907:Antibodies, Bacterial / Q000097:blood; D000917:Antibody Formation; D002648:Child; D002675:Child, Preschool; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007108:Immune Tolerance; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008297:Male; D011008:Pneumococcal Infections / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000627:therapeutic use*; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000472:pathogenicity
D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines
Hyporesponsiveness; Invasive pneumococcal disease; Opsonophagocytic assay; Pneumococcal vaccine