Search

Abstract: Aim:: In a prospective controlled study in young children with a history of recurrent acute otitis media, we analyzed the salivary IgA and IgG antibody titers upon vaccination with a 7-valent pneumococcal conjugate vaccine (PCV) given once or twice, followed by a 23-valent polysaccharide booster vaccination. Methods:: Salivary IgA and IgG antibody concentrations to vaccine serotype 6B, 14, 18C and 19F were measured by enzyme immunoassay in 38 samples of children vaccinated with PCV and 45 control samples. In the PCV group, 12 samples were taken prior to vaccination, 12 samples 4 weeks after the polysaccharide booster (8 months after the first conjugate vaccination) and 14 samples 7 months after the last vaccination (14 months after the first conjugate vaccination). In the control group 15 children were sampled at each of these three time points. Results:: We observed an increase in salivary IgG antibody concentrations against serotype 6B, 14, and 18C 14 months after the primary vaccination in children vaccinated with PCV twice, although this was significant for serotype 14 only. There was no increase in salivary IgG antibody in children vaccinate with PCV once nor in control children. IgA antibody titers increased significantly after 8 and after 14 months in both the pneumococcal vaccine recipients and the controls. However, the observed increase in mean antibody titers was significantly higher in control children compared to the PCV group. Conclusion:: We suggest that repeated pneumococcal conjugate vaccination is necessary to induce an increase in salivary IgG antibodies and effectuate clearance of S. pneumoniae from the nasopharyngeal mucosa of children with recurrent acute otitis media. We hypothesize that the increase in salivary IgA is caused by the local boosting of the mucosal immune response by carriage and recurrent infections, which occurs less often in the PCV group compared to the control children. [Copyright &y& Elsevier]

The efficacy of pneumococal conjugate vaccines in young children may be complicated by serotype replacement. We developed a colony blot assay which enables the identification of re-colonization with novel serotypes (replacement), overgrowth by minor co-colonizing serotypes or suppression of previously predominant vaccine serotype strains as a result of vaccination. This method allows the identification of multiple serotypes in a single specimen in a ratio of 1:1000. In order to demonstrate the potential of our method, we investigated the consecutive nasopharyngeal samples of 26 children who had shown a shift in pneumococcal colonization after conjugate vaccination. Mixed colonization was found once in 15 pre-vaccination samples and four times in 26 post-vaccination samples. In the remaining children `true replacement'' had presumably occurred. Hence, we conclude that the colony blot assay is an easy to apply method, which allows the identification of different pneumococcal serotypes within single clinical specimens. [Copyright &y& Elsevier]

Introduction. The objective was to measure the influence of recurrent acute otitis media (AOM) on the quality of life (QoL) in children. This study is part of the OMAVAX trial into the efficacy of vaccination with pneumococcal conjugate vaccine in children with recurrent AOM. Methods. QoL was measured in 306 children, aged 1–6 years, with validated questionnaires, RAND (general health), FS II R (FS-g = functional status in general, FS-s = illness-specific functional status), OM-6 (ear related QoL) and a self-developed questionnaire to measure family burden. Results. Children with four or more AOM episodes a year, so-called otitis-prone children, scored significantly worse than children with two or three AOM episodes a year on the RAND (P = 0.005), FS II R (FS-g P = 0.007; FS-s P = 0.003) and the OM-6 (P = 0.001). The parents of otitis-prone children do not experience a heavier family burden than parents of children with two or three AOM episodes (P = 0.1). Conclusion. Recurrent AOM has a negative influence on the QoL in children and symptoms increase with the number of AOM episodes. Prevention of AOM, for example by vaccination with a pneumococcal vaccine, would be valuable. [ABSTRACT FROM AUTHOR]

Background: Knowledge about the effect of recurrent acute otitis media (rAOM) and its treatment on health-related quality of life (HRQoL) and functional health status (FHS) in children with rAOM is limited. The current study aims to assess the effect of pneumococcal vaccination on HRQoL and FHS in children aged 1–7 years with rAOM. Methods: In a double-blind randomized controlled trial, 383 children aged 1–7 years with rAOM were vaccinated with either heptavalent pneumococcal conjugate vaccine followed by pneumococcal polysaccharide vaccine (pneumococcal group, n=190), or hepatitis A or B vaccine (control group, n=193). At baseline, age-adjusted HRQoL and FHS scores of all children were compared to those of reference populations. Subsequently, scores of the pneumococcal and control vaccine group were compared at baseline and at 7, 14, and 26 months follow-up. Data are presented for two instruments, NRS Child and FSQ Generic, assessing HRQoL and FHS, respectively. Results: Scores on the FSQ Generic of children with rAOM were lower than those of healthy children and comparable to those of children with asthma. After vaccination, no differences on the FSQ Generic or NRS Child were found between the pneumococcal and the control group at baseline and during follow-up. Conclusions: Recurrent acute otitis media has a considerable impact on the HRQoL and FHS of children; however, pneumococcal vaccination had no beneficial effect on their HRQoL and FHS. [Copyright &y& Elsevier]