Serum type (IgG, IgM and IgA-class) and secretory type antibodies specific to Streptococcus pneumoniae (Pn), Haemophilus influenzae (Hi) and Branhamella catarrhalis (Br) were measured by enzyme-linked immunosorbent assay (ELISA) in 46 serum and 114 middle ear effusion (MEE) samples from 85 children with acute otitis media (AOM). The samples were obtained within 12 h from the onset of the ear symptoms. Serum (but not secretory) type antibodies to the infecting Pn serotype were found in 24% of the MEE samples of the patients with Pn AOM and, correspondingly, serum and/or secretory type antibodies to Hi and Br were seen in 54% and 63% of the MEE samples of the patients with Hi or Br AOM, respectively. Moreover, antibodies against bacteria other than the causative one could also be found in the MEE. The occurrence of the serum type antibodies against these bacteria in the MEE was closely correlated with their serum levels. The findings of this study indicate that during the very early phase of AOM, the MEE contains both serum type antibodies originating from the serum, and secretory antibodies of middle ear origin. Among them there are antibodies specific to the three most common bacteria causing AOM (Pn, Hi, and Br) regardless of the bacterial etiology of the AOM attack in question.
In order to determine antibody levels against Streptococcus pneumoniae (pneumococcus) and Haemophilus influenzae type b (Hib) in a population of splenectomized subjects, 561 persons in a Danish county, splenectomized between 1984 and 1993 were identified. Two hundred and thirty-five were alive and 149 participated in the study. Each person donated a blood sample for antibody determination by ELISA. Though vaccine coverage among the 149 persons was 91% only 52% had 'protective' levels of pneumococcal antibodies. Despite recommendations for regular follow-up on pneumococcal antibody levels this had only been carried out in 4% of the subjects. Splenectomized subjects who needed pneumococcal revaccination were significantly more likely to have received their initial vaccination less than 14 days before or after splenectomy, as recommended, than those not requiring revaccination. Therefore, the timing of initial pneumococcal vaccination in relation to splenectomy seems to be important. All persons had Hib antibody levels higher than 0.15 microgram/ml and 60% had levels higher than 1 microgram/ml, which are the levels thought to provide short term and long term protection, respectively. In total, 37% of the 149 persons tested had pneumococcal and Hib antibody levels thought to correlate with protection from serious infections.
BACKGROUND: A substantial proportion of patients admitted to the hospital for pneumonia have been treated in a hospital during the preceding 4 to 5 years, and patients previously treated in a hospital for pneumonia seem to be at an especially high risk for another episode of pneumonia. Many cases of pneumococcal infection might therefore be prevented by immunizing admitted patients with pneumococcal vaccine at discharge or at follow-up. The aim of this study was to investigate the type-specific antibody response to pneumococcal vaccine in middle-aged and elderly patients at follow-up 8 weeks after hospital treatment for pneumonia. METHODS: A total of 92 individuals, 50 to 85 years old, participated in the study. One group consisted of 65 individuals treated in the hospital for pneumonia 8 weeks before vaccination (mean age, 67 years), and another group consisted of 27 individuals who had not recently been treated for pneumonia (mean age, 67 years). All 92 individuals received a single dose of a 23-valent pneumococcal vaccine. The type-specific antibody responses to six pneumococcal capsular polysaccharide antigens included in the vaccine as well as antibodies against the 23-valent pneumococcal vaccine were measured before and 3 to 4 weeks after vaccination by use of an enzyme-linked immunosorbent assay. RESULTS: The antibody concentrations before and after vaccination were comparable in the two groups, as were antibody fold increases from prevaccination to postvaccination serum. No serious adverse events were recorded. CONCLUSIONS: Pneumococcal vaccination at follow-up 8 weeks after treatment in the hospital for pneumonia seems to elicit an adequate antibody response without notable adverse reactions.
Pneumococcal surface adhesin A (PsaA) and pneumolysin (Ply) are common to virtually all Streptococcus pneumoniae isolates, and they are immunogenic and protective against pneumococcal challenge in experimental animals. We have recently shown production of antibodies to PsaA and Ply in young children, but data on the immune response to these antigens during culture-confirmed pneumococcal infection are lacking.
To evaluate whether young children respond to S. pneumoniae by producing antibodies to PsaA and Ply during acute otitis media (AOM).
A cohort of 329 children was followed prospectively from the age of 2 months to the age of 2 years. Paired sera were obtained during episodes of AOM and used to measure antibodies to PsaA and Ply by enzyme-linked immunosorbent assay. S. pneumoniae cultured from the middle ear fluid was taken as evidence of pneumococcal AOM. The presence of S. pneumoniae in the nasopharyngeal aspirate collected in connection of AOM or any other respiratory infection or in the nasopharyngeal swab collected at scheduled visits was taken to indicate pneumococcal carriage and thus a history of previous contact with S. pneumoniae.
Children with previous pneumococcal contacts had high anti-PsaA and anti-Ply concentrations in the acute phase sera regardless of the nature (AOM or carriage) of the current pneumococcal contact. Of the children with no previous pneumococcal contact, those with current pneumococcal AOM had lower antibody concentrations than those with current pneumococcal carriage only. Anti-PsaA and anti-Ply responses were found in children with current pneumococcal contact. The antibody response was strongly associated with low acute phase antibody concentration, but not significantly with age and the nature of the current pneumococcal contact.
We showed that infants are capable of developing a specific antibody response to the pneumococcal proteins PsaA and Ply during AOM.
Streptococcus pneumoniae carriage is often asymptomatic but can cause invasive pneumococcal disease. Pneumococcal carriage is a prerequisite for disease, with children as main reservoir and transmitters. Childhood carriage can therefore be used to determine which serotypes circulate in the population and which may cause disease in the non-vaccinated population. In 2006, a pneumococcal conjugate vaccine (PCV7) was introduced into the Norwegian Childhood Immunisation Programme, which was replaced by the more valent PCV13 in 2011. We investigated changes in pneumococcal carriage prevalence 4 years after switching to PCV13 compared to three previous surveys, and analysed factors associated with carriage in children.
We conducted a cross-sectional study in Norway, autumn 2015, among children attending day-care centres. We collected questionnaire data and nasopharyngeal swabs to identify pneumococcal serotypes. We compared the carriage prevalence in 2015 with surveys conducted in the same setting performed before widespread vaccination (2006; n?=?610), 2 years after PCV7 introduction (2008; n?=?600), and 2 years after switching to PCV13 (2013; n?=?874). Using multilevel logistic regression we determined the association between pneumococcal carriage and previously associated factors.
In 2015, 896 children participated, with age ranging from 8 to 80?months. The overall carriage prevalence was 48/100 children [95%CI 44-53] in 2015, 38% [29-46] lower than in 2006 pre-PCV7, and 23% [12-32] lower than in 2013, 2 years after switching to PCV13. The PCV13 carriage prevalence was 2.8/100 children [1.9-4.2] in 2015. Increasing age (p?
The antibody response to pneumococcal glycoconjugate (Pnc) was characterized by analyzing pneumococcal polysaccharide (PPS)-- and protein carrier-specific IgG subclass profiles and their relationship. Mice were immunized intranasally (inl) or subcutaneously (sc) with Pnc with mutants of Escherichia coli heat-labile enterotoxin, LT-R72 and LT-K63, as mucosal adjuvants. Subcutaneous immunization with Pnc alone induced predominantly IgG1, whereas native PPS administered sc induced very low IgG titers that were exclusively of the IgG3 subclass. Compared with sc immunization with Pnc alone, inl immunization with Pnc and LT mutants induced significantly higher systemic IgG2a, IgG3, and IgA antibodies to both PPS and the carrier, whereas the IgG1 titers were comparable. There also was a significant correlation between PPS- and protein carrier--specific antibody responses for all IgG subclasses. This demonstrates that LT mutants can be used to both enhance and modulate the antibody response to the PS moiety of glycoconjugate vaccines.