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O'Connor D, Png E, Khor CC, Snape MD, Hill AVS, van der Klis F, Hoggart C, Levin M, Hibberd ML, Pollard AJ. Common Genetic Variations Associated with the Persistence of Immunity following Childhood Immunization. Cell Rep 2020; 27:3241-3253.e4. [PMID: 31189108 DOI: 10.1016/j.celrep.2019.05.053] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/25/2019] [Accepted: 05/15/2019] [Indexed: 12/22/2022] Open
Abstract
Vaccines have revolutionized public health, preventing millions of deaths each year, particularly in childhood. Yet, there is considerable variability in the magnitude and persistence of vaccine-induced immunity. Maintenance of specific antibody is essential for continuity of vaccine-induced serological protection. We conducted a genome-wide association study into the persistence of immunity to three childhood vaccines: capsular group C meningococcal (MenC), Haemophilus influenzae type b, and tetanus toxoid (TT) vaccines. We detail associations between variants in a locus containing a family of signal-regulatory proteins and the persistence MenC immunity. We postulate a regulatory role for the lead SNP, with supporting epigenetic and expression quantitative trait loci data. Furthermore, we define associations between SNPs in the human leukocyte antigen (HLA) locus and the persistence of TT-specific immunity. Moreover, we describe four classical HLA alleles, HLA DRB1∗0301, HLA DQB1∗0201, HLA DQB1∗0602, and HLA DRB1∗1501, associated with TT-specific immunity, independent of the lead SNP association.
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Affiliation(s)
- Daniel O'Connor
- Department of Paediatrics, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK.
| | - Eileen Png
- Infectious Diseases, Genome Institute of Singapore, Singapore, Singapore
| | - Chiea Chuen Khor
- Infectious Diseases, Genome Institute of Singapore, Singapore, Singapore
| | - Matthew D Snape
- Department of Paediatrics, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Adrian V S Hill
- NIHR Oxford Biomedical Research Centre, Oxford, UK; Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Fiona van der Klis
- Centre for Infectious Disease Control Netherlands, RIVM, Bilthoven, the Netherlands
| | - Clive Hoggart
- Division of Infectious Diseases, Department of Medicine, Imperial College London, London, UK
| | - Michael Levin
- Division of Infectious Diseases, Department of Medicine, Imperial College London, London, UK
| | - Martin L Hibberd
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK; Department of Pathogen Molecular Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Andrew J Pollard
- Department of Paediatrics, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK
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Oliver JL, Sadorge C, Boisnard F, Snape MD, Tomlinson R, Mann R, Rudd P, Bhakthavalsala S, Faust SN, Heath PT, Hughes SM, Borrow R, Thomas S, Finn A. Randomized clinical trial of DTaP5-HB-IPV-Hib vaccine administered concomitantly with meningococcal serogroup C conjugate vaccines during the primary infant series. Vaccine 2020; 38:5718-5725. [DOI: 10.1016/j.vaccine.2020.06.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 11/29/2022]
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Marshall ASJ, Barker CIS, Pulickal AS, Kibwana E, Gautam SC, Clutterbuck EA, Thorson SM, Shrestha S, Adhikari N, Pollard AJ, Kelly DF. The seroepidemiology of Haemophilus influenzae type b prior to introduction of an immunization programme in Kathmandu, Nepal. PLoS One 2014; 9:e85055. [PMID: 24465475 PMCID: PMC3898912 DOI: 10.1371/journal.pone.0085055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Accepted: 11/21/2013] [Indexed: 11/19/2022] Open
Abstract
Haemophilus influenzae type b (Hib) is now recognized as an important pathogen in Asia. To evaluate disease susceptibility, and as a marker of Hib transmission before routine immunization was introduced in Kathmandu, 71 participants aged 7 months-77 years were recruited and 15 cord blood samples were collected for analysis of anti-polyribosylribitol phosphate antibody levels by enzyme-linked immunosorbent assay. Only 20% of children under 5 years old had levels considered protective (>0.15 µg/ml), rising to 83% of 15-54 year-olds. Prior to introduction of Hib vaccine in Kathmandu, the majority of young children were susceptible to disease.
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Affiliation(s)
- Andrew S. J. Marshall
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
- * E-mail:
| | - Charlotte I. S. Barker
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Anoop S. Pulickal
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Elizabeth Kibwana
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | | | - Elizabeth A. Clutterbuck
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | | | | | | | - Andrew J. Pollard
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Dominic F. Kelly
- Oxford Vaccine Group, Oxford University, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
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Ladhani SN. Two decades of experience with the Haemophilus influenzae serotype b conjugate vaccine in the United Kingdom. Clin Ther 2012; 34:385-99. [PMID: 22244051 DOI: 10.1016/j.clinthera.2011.11.027] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 11/16/2011] [Accepted: 11/23/2011] [Indexed: 11/30/2022]
Abstract
BACKGROUND The Haemophilus influenzae serotype b (Hib) conjugate vaccine was introduced into the UK national childhood immunization program in 1992 after clinical trials reported the vaccine to be highly immunogenic in infants as young as two months of age. OBJECTIVE The goal of this study was to describe and comment on the impact of routine Hib immunization on the epidemiology of invasive Hib disease in the United Kingdom. In addition, the development of Hib polysaccharide and conjugate vaccines was reviewed. METHODS A literature search was conducted of PubMed for invasive Hib disease epidemiology in the United Kingdom. The UK Health Protection Agency Web site was also searched for relevant publications. RESULTS The incidence of invasive Hib incidence in children aged <5 years fell from 21/100,000 to 44/100,000 in the prevaccine era to 0.63/100,000 in 1998, with an estimated vaccine failure rate of 2.2/100,000 vaccinees. After 1999, however, invasive Hib disease increased, particularly in toddlers, and peaked in 2003. Potential reasons for the resurgence included a greater-than-expected decline in Hib antibodies after primary immunization, waning of herd immunity offered by the initial catch-up campaign, and use of a less immunogenic Hib combination vaccine containing acellular pertussis in 2000-2001. In response to the resurgence, a Hib combination vaccine containing whole-cell pertussis was reintroduced in 2002, followed by a childhood Hib booster campaign in 2003. In 2004, the recommended infant vaccine was changed to a different Hib/acellular pertussis combination vaccine containing inactivated polio, which had a satisfactory Hib response, was less reactogenic, and eliminated the risk of vaccine-associated paralytic poliomyelitis. This action was followed by introduction of a routine 12-month Hib booster in 2006. Together, these measures led to a decline in invasive Hib disease across all age groups. In 2010, there were only 30 invasive Hib cases, with 6 reported in children aged <5 years and no deaths in this age group since 2007. CONCLUSIONS Control of Hib disease is currently the best that has been achieved since the introduction of the routine Hib vaccination almost 20 years ago.
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Abstract
Polysaccharide-encapsulated organisms such as S. pneumoniae, H. influenzae type b and N. meningitidis are the leading causes of serious invasive bacterial diseases and pneumonia in children. The use of conjugate vaccines in developed countries has markedly decreased the burden of disease and mortality from these organisms through direct protection of the immunised and through herd immunity. Although conjugate vaccines are highly immunogenic, antibody levels after immunisation in early infancy wane, leading to the need for programmes which include booster doses. Understanding the generation of long-term immunity could lead to improvements in vaccine formulation and scheduling with the ultimate goal of providing more sustained protection. Prematurity is a risk factor for disease caused by polysaccharide-encapsulated bacteria and the available data indicate that preterm infants should be immunised according to their chronological age to provide early protection.
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Affiliation(s)
- Johannes Trück
- Department of Paediatrics, University of Oxford, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, Headington, UK.
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Ladhani S, Heath PT, Aibara RJ, Ramsay ME, Slack MPE, Hibberd ML, Pollard AJ, Moxon ER, Booy R. Long-term complications and risk of other serious infections following invasive Haemophilus influenzae serotype b disease in vaccinated children. Vaccine 2010; 28:2195-2200. [PMID: 20056189 DOI: 10.1016/j.vaccine.2009.12.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 12/10/2009] [Accepted: 12/23/2009] [Indexed: 10/20/2022]
Abstract
This study describes the long-term complications in children with Haemophilus influenzae serotype b (Hib) vaccine failure and to determine their risk of other serious infections. The families of 323 children with invasive Hib disease after appropriate vaccination (i.e. vaccine failure) were contacted to complete a questionnaire relating to their health and 260 (80.5%) completed the questionnaire. Of the 124 children with meningitis, 18.5% reported serious long-term sequelae and a further 12.1% of parents attributed other problems to Hib meningitis. Overall, 14% (32/231 cases) of otherwise healthy children and 59% (17/29 cases) of children with an underlying condition developed at least one other serious infection requiring hospital admission. In a Poisson regression model, the risk of another serious infection was independently associated with the presence of an underlying medical condition (incidence risk ratio (IRR) 7.6, 95% CI 4.8-12.1; p<0.0001), both parents having had a serious infection (IRR 4.1, 95% CI 1.6-10.3; p=0.003), requirement of more than two antibiotic courses per year (IRR 2.3, 95% CI 1.4-3.6; p=0.001) and the presence of a long-term complication after Hib infection (IRR 1.8, 95% CI 1.1-3.1; p=0.03). Thus, rates of long-term sequelae in children with vaccine failure who developed Hib meningitis are similar to those in unvaccinated children in the pre-vaccine era. One in seven otherwise healthy children (14%) with Hib vaccine failure will go on to suffer another serious infection requiring hospital admission in childhood, which is higher than would be expected for the UK paediatric population.
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Affiliation(s)
- Shamez Ladhani
- Academic Unit of Paediatrics, Barts and The London School of Medicine and Dentistry, London, United Kingdom.
| | - Paul T Heath
- Vaccine Institute and Division of Child Health, St George's, University of London, United Kingdom
| | - Rashna J Aibara
- Department of Paediatrics, Central Middlesex Hospital, London, United Kingdom
| | - Mary E Ramsay
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | - Mary P E Slack
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | - Martin L Hibberd
- Infectious Diseases Unit, Genome Institute of Singapore, Republic of Singapore
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, United Kingdom
| | - E Richard Moxon
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, United Kingdom
| | - Robert Booy
- Academic Unit of Paediatrics, Barts and The London School of Medicine and Dentistry, London, United Kingdom; National Centre for Immunisation Research & Surveillance, University of Sydney, Australia
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7
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Anti-polyribosylribitol phosphate antibody concentrations and avidities in children since the start of Haemophilus influenzae type b immunization of infants in the United Kingdom. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 16:246-52. [PMID: 18784340 DOI: 10.1128/cvi.00023-08] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The introduction of routine infant immunization with Haemophilus influenzae type b (Hib) conjugate vaccines in the United Kingdom in 1992 led to a significant reduction in invasive disease due to this organism. Subsequently, between 1999 and 2003 there was an increase in the number of immunized children with Hib infection. We investigated whether the rise in cases was related to changes in anti-polyribosylribitol phosphate (PRP) antibody concentration or avidity. Using stored sera, we analyzed temporal changes in antibody levels among 3- to 5-year-old children immunized between 1991 and 2000. Anti-PRP antibody concentrations were higher in 3- to 5-year-olds who received infant immunization in 1991 than those in subsequent years. This difference may be related to changes in either the mode of administration of Hib conjugate vaccines or the rates of Hib nasopharyngeal carriage. This study emphasizes the factors affecting anti-PRP antibody concentration following immunization with conjugate vaccines and the importance of these in long-term protection from invasive disease.
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Oh S, Griffiths D, John T, Lee Y, Yu L, McCarthy N, Heath P, Crook D, Ramsay M, Moxon E, Pollard A. School‐Aged Children: A Reservoir for Continued Circulation ofHaemophilus influenzaeType b in the United Kingdom. J Infect Dis 2008; 197:1275-81. [DOI: 10.1086/586716] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Berrington JE, Cant AJ, Matthews JNS, O'Keeffe M, Spickett GP, Fenton AC. Haemophilus influenzae type b immunization in infants in the United Kingdom: effects of diphtheria/tetanus/acellular pertussis/Hib combination vaccine, significant prematurity, and a fourth dose. Pediatrics 2006; 117:e717-24. [PMID: 16549502 DOI: 10.1542/peds.2005-0348] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE To measure anti-polyribosylribitolphosphate (PRP) antibody and anti-tetanus toxoid (TT) antibody responses in UK infants to explore the effects of (1) immunization with an acellular diphtheria/tetanus/pertussis/Haemophilus influenzae type b (DTPHib) combination vaccine, (2) significant preterm delivery, and (3) a fourth dose of conjugated Hib vaccine (PRP-T) in those with a low anti-PRP antibody (<1.0 microg/mL) after primary immunization. METHODS A prospective study was conducted in 4 tertiary neonatal units at a time when 2 types of DTPHib vaccines were used interchangeably in the United Kingdom for primary immunization: acellular (DTPaHib) and whole cell. Timing and type of all vaccine doses were as per standard UK practice. Blood was taken before and after immunization. A total of 166 preterm and 45 term infants completed the study; 97 (15 term) infants who had anti-PRP antibody <1.0 microg/mL were offered a fourth dose of PRP-T; 61 (55 preterm) then had repeat antibody measurements. Anti-PRP and anti-TT antibody after primary immunization relative to gestation and number of whole cell vaccine doses received was measured, as well as anti-PRP antibody after a fourth dose of PRP-T. RESULTS A total of 49% of preterm and 33% of term infants had anti-PRP antibody <1.0 microg/mL after full primary immunization. Receipt of 1 or more acellular vaccine doses was associated with lower anti-PRP antibody, a dose response effect being observed. Preterm infants were less likely to have anti-PRP antibody >1.0 microg/mL compared with term infants. A total of 93% of infants who were given a fourth dose had anti-PRP antibody >1.0 microg/mL. Anti-TT antibody responses were satisfactory for all infants but also reduced by each DTPaHib dose received. CONCLUSION Infants who receive DTPaHib, are significantly preterm, or who do not receive a fourth dose of conjugated Hib vaccine may be at increased risk for Hib disease.
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Affiliation(s)
- Janet E Berrington
- Department of Neonatology, Royal Victoria Infirmary, Newcastle Upon Tyne, England
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10
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Booy R, Haworth EA, Ali KA, Chapel HM, Moxon ER. Immunogenicity of routine vaccination against diphtheria, tetanus, and Haemophilus influenzae type b in Asian infants born in the United Kingdom. Arch Dis Child 2005; 90:589-91. [PMID: 15908622 PMCID: PMC1720432 DOI: 10.1136/adc.2004.064469] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To determine the immunogenicity of routine vaccination against diphtheria, tetanus, and Haemophilus influenzae type b (Hib) in Asian infants born in the UK, and whether maternal antibody suppression occurs. METHODS A cohort study with 80% power, within 95% confidence limits, to show that 80% or fewer Asian infants would respond with an anti-PRP antibody concentration >0.15 microg/ml. Infants of South Asian origin born in Berkshire were enrolled at two general practices in Reading: 41 Asian families sequentially asked to participate within 2 weeks of birth; 36 infants were enrolled and 34 completed the study. Main outcome measures were: antibody concentration against diphtheria, tetanus, and Hib expressed as geometric mean titres (GMT) and proportion of infants about a threshold protective antibody concentration. RESULTS Median age for completing primary vaccination course was 5 months. All 34 achieved anti-PRP antibody concentration of >0.15 microg/ml, 33 were >1.0 microg/ml, and the GMT was 15.0 microg/ml. All infants developed protective antibody concentration >0.1 IU/ml for tetanus and diphtheria; the respective GMTs were 1.94 and 5.57 IU/ml. Infants with high (>0.25 IU/ml) antibody concentrations against diphtheria and tetanus at 2 months achieved lower antibody concentrations after their three dose course than those with low concentrations (<0.1 IU/ml) (p = 0.06 and 0.03, respectively). CONCLUSIONS Despite evidence for maternal antibody suppression of the response to tetanus and diphtheria vaccination, excellent antibody responses were achieved by routine vaccination according to the accelerated schedule. High vaccine coverage should be encouraged to provide protection against the possibility of imported infection.
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Affiliation(s)
- R Booy
- Research Centre for Child Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK.
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11
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Ferry BL, Misbah SA, Stephens P, Sherrell Z, Lythgoe H, Bateman E, Banner C, Jones J, Groome N, Chapel HM. Development of an anti-Salmonella typhi Vi ELISA: assessment of immunocompetence in healthy donors. Clin Exp Immunol 2004; 136:297-303. [PMID: 15086394 PMCID: PMC1809015 DOI: 10.1111/j.1365-2249.2004.02439.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
We have developed a solid-phase enzyme-linked immunosorbent assay (ELISA) to study the vaccination responses to Vi capsular polysaccharide of Salmonella typhi (S. typhi Vi) vaccine. Purified S. typhi Vi polysaccharide was biotinylated and bound to streptavidin coated microtitre plates. Reproducibility was determined across a range of IgG antibody levels: mean interassay coefficients of variation (CVs) were <11.9% for non-vaccinated sera with low levels and <11.1% for sera with very high levels of anti-S. typhi Vi IgG. Specificity was assessed by inhibition studies using salmonella antigen. We have developed the ELISA based on normal adult serum responses to test immunization with S. typhi Vi vaccine. We also report here anti-S. typhi Vi IgG levels in a group of healthy preschool children. In non-vaccinated adult sera (n = 104), the median value of anti-S. typhi Vi IgG, expressed in S. typhi Vi arbitrary units (AU/ml), was 5.3 AU/ml and in non-vaccinated sera from children (n = 44) the median value was 1.4 AU/ml. The data from immunization of healthy volunteers (n = 23) show that geometric mean levels of anti-S. typhi Vi IgG were significantly higher (P < 0.0001) for post-vaccination subjects (39.2 AU/ml) compared to paired prevaccination (3.9 AU/ml) values. A total of 21/23 vaccine recipients had <8 AU/ml S. typhi Vi IgG in their sera prior to vaccination and of these 20/21 (95%) exhibited threefold increases and 14/21 (67%) fourfold increases in their S. typhi Vi IgG following vaccination. Based on the data in this study, we propose a threefold increase in anti-S. typhi Vi IgG post-vaccination to be considered a positive vaccination response. The ability to demonstrate clearly an antibody rise in response to immunization with S. typhi Vi capsular polysaccharide vaccine suggests that this is likely to be a useful vaccine for the assessment of B cell function in patients with suspected immune deficiency.
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Affiliation(s)
- B L Ferry
- Department of Clinical Immunology, Oxford Radcliffe Hospitals, Oxford, UK.
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12
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Abstract
Based on a unique nationwide registration of vaccinated children, we studied the impact of routine Hib vaccination with special emphasis on vaccine uptake and adherence, vaccine effectiveness with respect to Hib meningitis, and indirect effects with respect to Hib meningitis among the unvaccinated children. Uptake and adherence was generally satisfactory. We estimated >97% effectiveness for all three doses of vaccine and observed herd-immunity in unvaccinated children comparable to a vaccine effectiveness of 94% 3.5 years into the programme. In conclusion, nationwide routine Hib vaccination is highly effective in protecting against Hib meningitis, and rapid achievement of herd immunity is possible with catch-up vaccination of older children.
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Affiliation(s)
- Anders Hviid
- Department of Epidemiology Research, Danish Epidemiology Science Centre, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen S, Denmark.
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13
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McVernon J, Johnson PDR, Pollard AJ, Slack MPE, Moxon ER. Immunologic memory in Haemophilus influenzae type b conjugate vaccine failure. Arch Dis Child 2003; 88:379-83. [PMID: 12716702 PMCID: PMC1719572 DOI: 10.1136/adc.88.5.379] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To compare the convalescent antibody response to invasive Haemophilus influenzae type b (Hib) disease between conjugate vaccine immunised and unimmunised children, to look for evidence of priming for immunologic memory. METHODS Unmatched case-control study in the UK and Eire 1992-2001 and Victoria, Australia 1988-1990. A total of 93 children were identified as having invasive Hib disease following three doses of conjugate vaccine in infancy through post licensure surveillance throughout the UK and Eire; 92 unvaccinated children admitted to an Australian paediatric hospital with invasive Hib disease were used as historical controls. Convalescent serum was taken for measurement of Hib antibody concentration, and clinical information relating to potential disease risk factors was collected. The geometric mean concentrations of convalescent Hib antibodies were compared between immunised and unimmunised children, using raw and adjusted data. RESULTS Hib conjugate vaccine immunised children had higher serum Hib antibody responses to disease (geometric mean concentration (GMC) 10.81 microg/ml (95% CI 6.62 to 17.66) than unimmunised children (1.06 microg/ml (0.61 to 1.84)) (p < 0.0001). However, following adjustment for the significant confounding influences of age at presentation and timing of serum collection, a difference persisted only in children presenting with meningitis (vaccinated GMC 3.78 microg/ml (2.78 to 5.15); unvaccinated GMC 1.48 microg/ml (0.90 to 2.21); p = 0.003). CONCLUSIONS Higher antibody responses to invasive Hib disease in vaccinated children with meningitis reflect priming for immunologic memory by the vaccine. Although a majority of children in the UK are protected from Hib disease by immunisation, the relative roles of immunologic memory and other immune mechanisms in conferring protection remain unclear.
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Affiliation(s)
- J McVernon
- Oxford Vaccine Group, University of Oxford Department of Paediatrics, John Radcliffe Hospital, Oxford, UK.
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Heath PT, Booy R, McVernon J, Bowen-Morris J, Griffiths H, Slack MPE, Moloney AC, Ramsay ME, Moxon ER. Hib vaccination in infants born prematurely. Arch Dis Child 2003; 88:206-10. [PMID: 12598378 PMCID: PMC1719486 DOI: 10.1136/adc.88.3.206] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To document the immunogenicity and persistence of antibody to polyribosyl-ribitol phosphate (PRP) as well as the clinical protection against invasive Haemophilus influenzae type b (Hib) disease in premature infants immunised at the routine schedule. METHODS Blood was obtained at 2, 5, 12, and 64 months of age from a cohort of prematurely born infants (<or=32 weeks gestation). Anti-PRP antibody concentrations were compared with those of a control cohort of infants born at full term and vaccinated at the same schedule. Hib vaccine failures occurring between October 1992 and October 2000 were reported by paediatricians through an active, prospective, national survey in the UK and Republic of Ireland. The number of prematurely born children with vaccine failure was compared with the corresponding number born at term. RESULTS Twenty seven prematurely born infants were followed to 5 years of age. Compared with term infants they had a significantly lower geometric mean concentration of anti-PRP antibody and/or a significantly lower proportion above one or both of the conventional protective antibody concentrations (0.15 and 1.0 micro g/ml) at all ages. A total of 165 cases of invasive Hib disease were identified over eight years of national surveillance. Eighteen were premature (<37 weeks); approximately 12 would be expected. The relative risk of UK premature infants developing disease compared with term infants was 1.5 (95% CI 0.9 to 2.6). CONCLUSIONS Premature infants develop lower antibody concentrations than term infants following Hib conjugate vaccination. Premature infants may also have an increased risk of clinical vaccine failure, but interpretation is limited by the small number of premature infants developing invasive Hib disease over eight years of national surveillance. Overall, vaccination with Hib conjugate vaccines affords a high level of protection to premature babies.
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Affiliation(s)
- P T Heath
- Department of Child Health and St George's Vaccine Institute, St George's Hospital Medical School, London, UK.
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15
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Abstract
Haemophilus influenzae type b (Hib) is an important pathogen in children <5 years of age. The Hib conjugate vaccines were the first polysaccharide-protein conjugate vaccines to be used in routine childhood schedules. Their introduction in the UK in 1992 has resulted in the near elimination of Hib disease. The UK Hib vaccine programme has a number of unique features including an accelerated schedule, absence of a booster dose, and the inclusion of a catch up component at the beginning of the programme. Collaboration between UK paediatricians, microbiologists, and public health physicians has allowed active national surveillance of Haemophilus influenzae disease and enabled important conclusions to be drawn. These include high vaccine effectiveness, the presence of herd immunity, and the frequency of risk factors in cases of vaccine failure and in cases of invasive disease due to non-b H influenzae. Parallel studies have shown the immunogenicity, induction of immunological memory, and persistence of immunity following vaccination at the UK schedule, as well as measuring the impact of vaccination on pharyngeal Hib carriage. Cases continue to occur and complacency is ill advised, particularly as other vaccines and combinations are introduced. Surveillance of H influenzae disease in the UK remains important.
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Affiliation(s)
- P T Heath
- Department of Child Health and St George's Vaccine Institute, St George's Hospital Medical School, London, UK.
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16
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Heath PT, Booy R, Griffiths H, Clutterbuck E, Azzopardi HJ, Slack MP, Fogarty J, Moloney AC, Moxon ER. Clinical and immunological risk factors associated with Haemophilus influenzae type b conjugate vaccine failure in childhood. Clin Infect Dis 2000; 31:973-80. [PMID: 11049779 DOI: 10.1086/318132] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/1999] [Revised: 03/21/2000] [Indexed: 11/03/2022] Open
Abstract
Haemophilus influenzae type b (Hib) conjugate vaccines have proved extremely efficacious in healthy children. True Hib vaccine failures are rare. Hib conjugate vaccines were introduced for routine immunization in the United Kingdom and the Republic of Ireland in 1992. Coincident with this, active prospective and national surveillance via pediatricians, microbiologists, and public health physicians was commenced to assess the clinical and immunological factors associated with vaccine failure. During the 6 years of the study, 115 children with true vaccine failure were reported. Of the children who were vaccinated before 12 months of age, a clinical risk factor was detected in 20%, an immunological deficiency was detected in 30%, and one or both were detected in 44%. Children who were vaccinated after 12 months of age were more likely to have one or both factors (67%). Thirty percent (33 of 105) of children with true vaccine failure had a low Hib antibody response (concentration, <1.0 microg/mL) after disease, but the majority then responded to a further dose of Hib vaccine. Children who develop Hib disease despite vaccination deserve further clinical and immunological evaluation.
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Affiliation(s)
- P T Heath
- Oxford Vaccine Group, John Radcliffe Hospital, Oxford, United Kingdom.
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Spickett GP, Bullimore J, Wallis J, Smith S, Saunders P. Northern region asplenia register--analysis of first two years. J Clin Pathol 1999; 52:424-9. [PMID: 10562809 PMCID: PMC501428 DOI: 10.1136/jcp.52.6.424] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To assess the feasibility of setting up a register of patients with asplenia within a defined geographical area; to ensure that guidelines on best practice were implemented; to obtain information on antibody levels to pneumococcal capsular polysaccharides and Haemophilus influenzae type b capsular polysaccharide, before and after immunisation and annually thereafter; to raise awareness of risks among clinicians and to offer advice on management. DESIGN Prospective recruitment using multiple sources of recruitment. Annual follow up reminders sent from Registration Centre. SUBJECTS Population of (old, pre-1995) Northern Health Region: approximately 3.1 million. MAIN OUTCOME MEASURES Data were obtained on reasons for asplenia, duration of asplenia, use of prophylactic antibiotics, Medic-Alert bracelets, immunisations, antibody levels, death. RESULTS The register was initiated at the beginning of April 1995 and ran to the end of March 1997. After two years of operation, 1111 cases had been registered but the response from some health districts was poor. Major primary causes of asplenia were trauma (264), other surgical (198), lymphoproliferative disease (154), and idiopathic thrombocytopenic purpura (147). There were 664 patients on prophylactic antibiotics, of whom 498 were on continuous antibiotics. Only 18 had any type of warning bracelet. Antibody measurements were carried out at least once on 75% of patients; 306 patients had satisfactory antibody levels on first blood sample in year 1, rising to 405 in year 2; 43 patients failed to make any antibody response to Pneumovax despite multiple immunisations, and three patients failed to respond to Hib vaccine. Sixteen patients with satisfactory antibody levels in year 1 had low levels in year 2 requiring vaccine boosters. Sixteen deaths were reported, two of which were directly attributable to overwhelming sepsis. CONCLUSIONS Registration has been successful and has raised awareness of the management of asplenia. Compliance with antibiotic prophylaxis and immunisation was initially poor. A potential high risk group of vaccine non-responders has been identified and poor persistence of pneumococcal antibodies has been identified which is likely to alter approaches to immunisation in asplenic patients.
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Affiliation(s)
- G P Spickett
- Regional Department of Immunology, Royal Victoria Infirmary, Newcastle upon Tyne, UK
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Arvå E, Andersson B. Induction of phagocyte-stimulating cytokines by in vitro stimulation of human peripheral blood mononuclear cells with Haemophilus influenzae. Scand J Immunol 1999; 49:411-6. [PMID: 10219768 DOI: 10.1046/j.1365-3083.1999.00480.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to analyse the in vitro response of human peripheral blood mononuclear cells to stimulation with killed Haemophilus influenzae strains of different capsular types, isolation sites and from cases with different forms of infections. The mean stimulatory index using 10(6) bacteria/well was 10, and 80 when 10(8) bacteria/well were used for stimulation. The mean+/-SD level was 13+/-4 ng/ml for interleukin (IL)-1beta, 128+/-73 ng/ml for IL-6, 203+/-122 ng/ml for IL-8, 3160+/-1220 pg/ml for IL-10, 29+/-40 pg/ml for IL-12, 2800+/-1790 pg/ml for tumour necrosis factor (TNF)-alpha and 4+/-7 ng/ml for interferon (IFN)-gamma, when stimulating cells with the lower dose of 10(6) bacteria/well. Using the higher bacterial dose, the levels of IL-1beta, TNF-alpha and IL-12 remained similar, whereas the IL-6, IL-8 and IL-10 levels were significantly lower, and IFN-gamma levels were significantly higher. Strains isolated from the bronchial tree induced significantly higher levels of IFN-gamma and significantly lower levels of IL-6, IL-8 and IL-10 than strains from other isolation sites. In conclusion, H. influenzae generated phagocyte-activating cytokines and an IL-10/IL-12 ratio that was 1090 times that described previously for Streptococcus pneumoniae.
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Affiliation(s)
- E Arvå
- Department of Clinical Immunology, Göteborg, Sweden
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19
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Robinson MJ, Campbell F, Powell P, Sims D, Thornton C. Antibody response to accelerated Hib immunisation in preterm infants receiving dexamethasone for chronic lung disease. Arch Dis Child Fetal Neonatal Ed 1999; 80:F69-71. [PMID: 10325817 PMCID: PMC1720881 DOI: 10.1136/fn.80.1.f69] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To study the effect of dexamethasone on the routine immunisation of preterm infants with chronic lung disease. METHODS Serum samples were obtained before and after immunisation from an unselected cohort of 59 preterm infants. Haemophilus influenzae antibodies were measured using an ELISA method and differences in the geometric mean values between the two groups of babies analysed. RESULTS Sixteen infants received no dexamethasone. Before and after immunisation antibody titres for those receiving no dexamethasone were 0.16 and 4.63 mcg IgG/ml. Corresponding values for those receiving dexamethasone were 0.10 and 0.51 mcg IgG/ml, respectively. CONCLUSION Dexamethasone used in the treatment of chronic lung disease seems to significantly affect the antibody response of preterm infants to immunisation against Haemophilus influenzae.
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Abstract
OBJECTIVE To scrutinize the experiences of those European countries that have played a central role in understanding the behavior of and vaccination for Haemophilus influenzae type b (Hib) diseases, to enlighten weaknesses and to explore whether lessons learned would benefit other countries in combating Hib. DESIGN Epidemiologic and clinical data on Hib infections and vaccinations were analyzed, including all disease manifestations and all age groups. To improve reliability, sources that used active case finding were especially searched for. RESULTS In the prevaccination era meningitis represented 40 to 70% of all classical Hib diseases. Epiglottitis was the second most common presentation, except in southern Europe (data not available from former socialist countries). The overall incidence of meningitis and of all Hib disease combined for children ages 0 to 4 years was 23 and 41 per 100000, suggesting 9900 and 17800 cases per year, respectively. Including all age groups and entities, >20000 Hib cases occurred annually. Vaccination, accomplished with two or three primary doses and a late booster, has almost eliminated Hib disease in >10 countries, and >10000 cases per year are prevented. An age analysis of Hib meningitis suggests that strong early immunogenicity is not as imperative in Europe as in some other regions. The incidence of non-type b H. influenzae infections has not increased. CONCLUSIONS With Hib epidemiology comparable with that in Europe, good protection is achieved by various conjugate vaccines also with two primary doses only. However, active research on the whole Hib issue should be a priority, especially in southern and eastern European countries.
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Affiliation(s)
- H Peltola
- Helsinki University Central Hospital, Hospital for Children and Adolescents, Finland
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21
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Berthet F, Prehn A, Suter R, Ethevenaux C, Seger RA. Protective immunogenicity of Haemophilus influenzae type b polysaccharide-tetanus protein conjugate vaccine in children who failed to respond to prior invasive H. influenzae type b disease. Pediatr Allergy Immunol 1998; 9:156-60. [PMID: 9814731 DOI: 10.1111/j.1399-3038.1998.tb00363.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
UNLABELLED A polyribosylribitol phosphate (polysaccharide)-tetanus protein conjugate vaccine (PRP-T) against Haemophilus influenzae type b (Hib) was evaluated for protective immunogenicity in 25 previously PRP-unimmunized children who had failed to develop protective PRP antibody levels (< 1 microg/ml) after prior invasive Hib disease at median age 10 months. Children under 21 months of age at time of PRP-T immunization received one, two or three doses. Serum was obtained for total PRP antibody, complement mediated bactericidal activity and specific IgG1 and IgG2 PRP antibodies before (n = 25), 1 to 2 months (n = 24) and > 5 months (n = 13) after completed vaccination. One to 2 months after immunization, all but one patient developed > 1 microg/ml of antibody (geometric mean level 50.7 microg/ ml). The non-responder developed protective antibody levels when tested at 6 months after vaccination. Twenty out of 22 sera had detectable complement mediated bactericidal activity (median dilution titer 1:24), 1-2 months after vaccination. Three patients failed to demonstrate PRP antibodies in the IgG1 or IgG2 subclasses, although two of them had protective (> 1 microg/ml) total antibody levels. The second post immunization sera showed persistence of the total PRP antibody levels (geometric mean level 38.2 microg/ml) as well as of the bactericidal activity (median dilution titer 1:32). CONCLUSION PRP-T conjugate vaccine is able to elicit a protective immune response in children who have low or unmeasurable PRP antibody levels after a systemic Hib infection.
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Affiliation(s)
- F Berthet
- Div. Immunology/Haematology, University Children's Hospital Zurich, Switzerland
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22
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Bell F, Heath P, Shackley F, MacLennan J, Shearstone N, Diggle L, Griffiths H, Moxon ER, Finn A. Effect of combination with an acellular pertussis, diphtheria, tetanus vaccine on antibody response to Hib vaccine (PRP-T). Vaccine 1998; 16:637-42. [PMID: 9569476 DOI: 10.1016/s0264-410x(97)84511-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Acellular pertussis vaccines provide protection against whooping cough with few adverse effects. Their introduction to routine immunisation programmes would be facilitated by their incorporation with other routinely administered vaccines. 262 infants were immunised with an acellular pertussis vaccine containing pertussis toxin and filamentous haemagglutinin, combined with diphtheria and tetanus toxoids. This vaccine was mixed with Haemophilus influenzae type b tetanus toxoid vaccine (PRP-T) so that infants received a single injection at age 2, 3 and 4 months. One month after the third dose the geometric mean titre of Hib IgG antibody was 0.48 microgram ml-1. Eighty-two percent of infants achieved a titre of 0.15 microgram ml-1, with only 27% achieving 1.0 microgram ml-1. This combination vaccine induced low Hib antibody responses when compared to other studies in which PRP-T was mixed with acellular or whole-cell pertussis vaccines. The combined vaccine did, however, appear to prime a subset of 35 infants for response to a fourth dose of PRP-T at 13 months of age, with a rise in GMT from 0.21 microgram ml-1 to 36.6 micrograms ml-1. These data have important implications for the introduction of combination acellular pertussis vaccines.
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Affiliation(s)
- F Bell
- Sheffield Institute for Vaccine Studies, University Department of Paediatrics, Sheffield Children's Hospital, U.K..
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23
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Heath PT, Bowen-Morris J, Griffiths D, Griffiths H, Crook DW, Moxon ER. Antibody persistence and Haemophilus influenzae type b carriage after infant immunisation with PRP-T. Arch Dis Child 1997; 77:488-92. [PMID: 9496180 PMCID: PMC1717421 DOI: 10.1136/adc.77.6.488] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To assess the persistence of serum Haemophilus influenzae type b antibodies and the prevalence of H influenzae type b carriage in a group of preschool age children previously vaccinated in infancy. DESIGN Names were randomly selected from immunisation records. Families were visited on five occasions over a period of 12 months and throat swabs were taken from all family members present, with blood obtained from children at the first and last visits. RESULTS One hundred and fifty three children at a median age of 3.6 years had a geometric mean titre (GMT) of 1.06 micrograms/ml (95% CI 0.80 to 1.38). Eight per cent had an undetectable antibody concentration, received a booster dose of plain PRP vaccine, and responded with concentrations > 2 micrograms/ml. GMT at 4.5 years of age was 0.89 microgram/ml (0.69 to 1.16). Twelve children who had been exposed to H influenzae had a GMT of 4.7 v 0.8 micrograms/ml for those without exposure. CONCLUSIONS Accelerated immunisation against H influenzae without a second year booster results in persistence of satisfactory serum concentrations of antibody to 4.5 years of age. In those with undetectable antibody, immunological memory may still be present.
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Affiliation(s)
- P T Heath
- Department of Paediatrics, John Radcliffe Hospital, Oxford
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24
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Kumar A, Dutta AK, Saili A, Nangia S, Dutta R. Immunogenicity and tolerance of H. influenzae type b, tetanus toxoid conjugate vaccine given concurrently or in combination. Indian J Pediatr 1997; 64:839-47. [PMID: 10771928 DOI: 10.1007/bf02725508] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The present prospective, open, controlled, randomised comparative trial was undertaken to evaluate the sero response and side effects of PRP-T Conjugate Vaccine (ACT-HIB) in infants and children aged 2 months and 16-24 months. Fifty four babies aged 2 months formed group A, 56 children aged 16-24 months formed group B. Groups A and B were further subdivided into two sub groups each destined to receive either PRP-T vaccine in association with DPT vaccine at different sites (I) or PRP-T and DPT both vaccines at the same site mixed in the same syringe (II). Group A received 3 doses at 2, 3 and 4 months of age and group B received one dose between 16-24 months. The Geometric mean titres of Anti PRP antibodies observed in primary immunisation schedule (A) and single dose vaccination schedule (B) were comparable and significantly higher to prevaccination titres. A serum anti PRP level of > 1.0 mcg/ml after immunisation is believed to correlate with long term protection. Ninety-six percent of infants in Group A and 98% in Group B achieved titres > 1.0 mcg/ml. The side effects were minimal, local and were comparable between the study and control groups, suggesting that PRP-T vaccine is highly immunogenic and well tolerated in Indian infants and children.
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Affiliation(s)
- A Kumar
- Department of Pediatrics, Kalawati Saran Children's Hospital, New Delhi
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25
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26
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Booy R, Heath PT, Slack MP, Begg N, Moxon ER. Vaccine failures after primary immunisation with Haemophilus influenzae type-b conjugate vaccine without booster. Lancet 1997; 349:1197-202. [PMID: 9130940 DOI: 10.1016/s0140-6736(96)06392-1] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Diseases of early childhood associated with Haemophilus influenzae type b (Hib) can now be prevented by vaccination. The rapid implementation of routine infant vaccination with Hib polysaccharide-tetanus protein conjugate (PRP-T) vaccine has allowed us to assess whether an accelerated 2, 3, and 4 month schedule can protect in the longer term without a booster dose and whether carrier priming influences protective efficacy. The degree of protection afforded by a catch-up programme with Hib oligosaccharide conjugate (HbOC) for older children was also assessed. METHODS Paediatricians and microbiologists in the UK were asked to report all cases of invasive H influenzae infection in children who had received at least one dose of Hib-conjugate vaccine. Serum samples from convalescent children were obtained and the isolate was verified. Efficacy was estimated by comparing observed rates of Hib disease in those who had been vaccinated with rates predicted by age adjustment of disease rates from the prevaccine era. FINDINGS Of 164 reports of invasive infection between Oct 1, 1992, and Oct 1, 1995, 43 were considered true vaccine failures. The estimated overall efficacy for three doses of PRP-T was 98.1% (95% CI 97.3-98.7%). Efficacy in infants aged 5-11 months was 99.1%, 12-23 months 97.3%, and 24-35 months 94.7%. In infants aged 3-11 months, who received their first dose of PRP-T after tetanus toxoid vaccination, disease was unlikely from 1 week after one dose of PRP-T vaccine (88.6% protection in the second to fourth weeks [66.8-97.7%]). The disease rate in vaccinated infants aged 2 months has declined year on year. In children aged 13 months to 2 years given HbOC, as a catch-up vaccine, the estimated efficacy was 94.0% (84.7-98.4%). INTERPRETATION A high degree of efficacy has been observed with PRP-T vaccine given as a three-dose schedule in infancy and with HbOC as a single dose in older children. Efficacy of PRP-T appears to be enhanced by carrier priming. Although with increasing age there was a small decline in efficacy of PRP-T, Hib disease is now close to being eliminated in the UK, and we suggest that a booster is not necessary in the second year of life.
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Affiliation(s)
- R Booy
- Department of Paediatrics, St Mary's Hospital, London, UK
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27
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Gibb D, Giacomelli A, Masters J, Spoulou V, Ruga E, Griffiths H, Kroll S, Giaquinto C, Goldblatt D. Persistence of antibody responses to Haemophilus influenzae type b polysaccharide conjugate vaccine in children with vertically acquired human immunodeficiency virus infection. Pediatr Infect Dis J 1996; 15:1097-101. [PMID: 8970219 DOI: 10.1097/00006454-199612000-00008] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Recurrent bacterial sepsis is common in pediatric HIV infection and immunization against Haemophilus influenzae type b (Hib) is recommended. Long term persistence of anti-Hib antibody and the need for, or timing of, a booster dose has not been adequately studied. METHODS Immunogenicity during a 12-month period following immunization with Hib-tetanus conjugate vaccine (ACT-HIB; Merieux) was evaluated in 48 vertically HIV-infected children and 36 uninfected children, born to HIV-positive mothers. A titer of anti-Hib polysaccharide antibody of > or = 0.15 microgram/ml was considered to indicate short term and > or = 1 microgram/ml long term protection. RESULTS At 1 month postvaccination 36 (100%) uninfected and 42 (88%) HIV-infected children achieved titers of > or = 1 microgram/ml. However, by 1 year titers had dropped below this value in 18 (43%) infected compared with only 4 (11%) uninfected children (chi square, 9.7; P = 0.002). Although the rate of fall of antibody titer was greater in uninfected than in infected children, this was no longer the case after adjustment for the 1-month postimmunization titer. The rate of antibody titer decline was not significantly related to HIV disease status or to either the age-related CD4 count at the time of immunization or the change in age-adjusted CD4 count during the 12 months after immunization. CONCLUSIONS Not only was the initial antibody response to Hib conjugate vaccine decreased in children with HIV infection and AIDS but also 1 year later only 57% of the initial responders had persisting titers above the level associated with long term protection. The need for reimmunization of children with HIV infection against Hib requires further evaluation.
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Affiliation(s)
- D Gibb
- Institute of Child Health, London, United Kingdom,
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28
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Bell F, Martin A, Blondeau C, Thornton C, Chaplais J, Finn A. Combined diphtheria, tetanus, pertussis, and Haemophilus influenzae type b vaccines for primary immunisation. Arch Dis Child 1996; 75:298-303. [PMID: 8984914 PMCID: PMC1511738 DOI: 10.1136/adc.75.4.298] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A total of 146 infants were immunised at ages 2, 3, and 4 months with a combined diphtheria, tetanus, pertussis (DTP)--Haemophilus influenzae type b (Hib) tetanus toxoid conjugate (PRP-T) vaccine (Pasteur Merieux) to assess the antibody response and adverse events associated with immunisation. Adverse events, including fever, were recorded by parents in a diary for three days following each injection. Blood was taken before the first immunisation and four weeks after the third immunisation to assess antibody response. Data were compared with those from historical controls who had received DTP and PRP-T vaccines by separate injection. The combined vaccine was well tolerated. Rates of local and general reactions were similar to those reported for infants immunised by separate injection. All infants achieved protective antibody titres (> 0.01 IU/ml) for diphtheria and tetanus; 98% acquired Hib (PRP) antibody > 0.15 microgram/ml and 82.5% > 1.0 microgram/ml. Pertussis antibody titres (pertussis toxin, filamentous haemagglutinin, total agglutinins, and agglutinins 2 and 3) showed appreciable rise following immunisation. DTP and PRP-T vaccines provide similar antibody responses and adverse effects whether mixed in the same syringe or administered by separate injection. The vaccines could be combined for use in the United Kingdom primary immunisation schedule.
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Affiliation(s)
- F Bell
- University of Department of Paediatrics, Sheffield Children's Hospital
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29
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Goldblatt D, Johnson M, Evans J. Antibody responses to Haemophilus influenzae type b conjugate vaccine in sickle cell disease. Arch Dis Child 1996; 75:159-61. [PMID: 8869201 PMCID: PMC1511645 DOI: 10.1136/adc.75.2.159] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To investigate the immunogenicity of Haemophilus influenzae type b (Hib) conjugate vaccines in children with sickle cell disease. DESIGN Open study. SETTING Haemoglobinopathy clinic. SUBJECTS Children with homozygous haemoglobin SS disease (HbSS), sickle haemoglobin C disease (HbSC), and sickle-beta thalassaemia disease (HbS-beta Thal). INTERVENTIONS Children over the age of 2 years received a single dose of Hib-tetanus toxoid conjugate vaccine (PRP-T). MAIN OUTCOME MEASURES Antibody response to Hib polysaccharide (PRP) approximately one month after vaccination. RESULTS 77 children over the age of 2 years were studied,, 55 with HbSS, 16 with HbSC, and six with HbS-beta Thal. Before vaccination, 44% had anti-PRP IgG titres less than the level associated with long term protection (1.0 microgram/ml). After a single dose of PRP-T all children mounted an antibody titre > 1 microgram/ml. Geometric mean anti-PRP IgG titre achieved postvaccination (45.2 micrograms/ml 95% confidence interval (CI) 31.6 to 64.8) was comparable to that of a healthy population. Children with HbSC, however, had a significantly higher antibody titre postvaccination (91.1 micrograms/ml; 95% CI 32.7 to 254.4) than the children with HbSS (36.7 micrograms/ml; 95% CI 25.1 to 52.9). CONCLUSIONS Children with a diagnosis of sickle cell disease who are over the age of 2 years make a vigorous antibody response to a single dose of PRP-T vaccine and hence we suggest unimmunised individuals in this group should receive a single dose of a Hib conjugate vaccine.
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Affiliation(s)
- D Goldblatt
- Immunobiology Unit, Institute of Child Health, London
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30
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Goldblatt D, Fairley CK, Cartwright K, Miller E. Interchangeability of conjugated Haemophilus influenzae type b vaccines during primary immunisation of infants. BMJ (CLINICAL RESEARCH ED.) 1996; 312:817-8. [PMID: 8608290 PMCID: PMC2350736 DOI: 10.1136/bmj.312.7034.817] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- D Goldblatt
- Immunobiology Unit, Institute of Child Health, London
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31
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Abstract
Pharyngeal carriage of Haemophilus influenzae type b (Hib) is important in the transmission of Hib organisms, the pathogenesis of Hib disease, and the development of immunity to the bacterium. The remarkable success of current vaccination programs against Hib has been due in part to the effect of conjugate Hib vaccines in decreasing carriage of Hib. This review explores evidence for this effect, and discusses the possible mechanisms of the mucosal influence of Hib conjugate vaccines.
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32
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Abstract
Haemophilus influenzae has long been recognised as a major cause of serious infection and mortality in children less than 5 years old. Prior to the introduction of Haemophilus influenzae type b (Hib) immunisation, the incidence of a child suffering an invasive Haemophilus infection was 20-50/100,000 in industrialised countries and up to ten times higher in developing regions. The introduction of a Hib vaccine programme results in a rapid and dramatic decline in the incidence of Hib infection in the susceptible childhood population. For example, within two years of the introduction of routine Hib vaccination of infants in the UK, the risk of serious Hib infection had fallen from 1:600 to 1:30,000 by 5 years of age. Many other European countries have introduced, or are in the process of introducing, a routine Hib immunisation programme. Because the epidemiology of Haemophilus influenzae infection is changing so dramatically, it is opportune to review Haemophilus influenzae as it was perceived in the pre-vaccine era (the past) and during vaccine implementation (the present), and how its role may change in the post-vaccination era (the future). This review will summarise the historical landmarks that have led to our present-day understanding of Haemophilus influenzae pathogenicity, the concerns about antibiotic resistance, the features of the host immune response to Haemophilus influenzae, and the introduction of the Hib vaccine. Furthermore, the possible importance of this organism in the future will be discussed.
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Affiliation(s)
- J Z Jordens
- Public Health Laboratory Service Haemophilus Reference Laboratory, John Radcliffe Hospital, Oxford, UK
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33
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Asensi F, Otero MC, Pérez-Tamarit D, Miranda J, Picó L, Nieto A. Economic aspects of a general vaccination against invasive disease caused by Haemophilus influenzae type b (Hib) via the experience of the Children's Hospital La Fe, Valencia, Spain. Vaccine 1995; 13:1563-6. [PMID: 8578843 DOI: 10.1016/0264-410x(95)00087-h] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
With the aim of studying whether a general vaccination against invasive disease caused by Haemophilus influenzae type b (Hib) is economically profitable bearing in mind the efficacy and safety of the vaccine, its price and the global cost that this disease has in our area, a review is conducted of patients admitted due to invasive disease caused by Hib in the Children's Hospital La Fe, Valencia, born between 1984 and 1993. They total 100, 63 who have meningitis. In the 81 cases (56 with meningitis) born between 1984 and 1990 (years that can be regarded as "closed" since all the patients were younger than 5 years of age) the total cost has been calculated for hospitalization, care during the acute phase, care for the sequelae (6 severe and 7 mild) and death (5 cases). The mean annual cost of care can be calculated at 62 million pesetas, without making an economic valuation of the loss of life, and at 205 million pesetas taking this factor into account. The annual cost of vaccinating the 7000 babies under one year of age and falling within the Hospital's catchment area, on the basis of a vaccination pattern of three doses (at 2, 4 and 6 months) or four doses (at 2, 4, 6 and 15 months) would amount to 63 or 84 million pesetas, normal price to public (not covered by National Health Service), and 40 or 51 million pesetas if acquired by National Health Service. As a conclusion we can state that, even from the economic point of view, without quantifying the cost of the loss of life, a public general anti-Hib vaccination would be profitable in our area since it would mean an administration cost lower than that of the care required by patients. This is without taking into account the fact that emotional, family and social serious disturbances would also be avoided due to hospitalization, sequelae and deaths caused by a disease which is today perfectly preventable.
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Affiliation(s)
- F Asensi
- University Children's Hospital La Fe, Valencia, Spain
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Anderson EC, Begg NT, Crawshaw SC, Hargreaves RM, Howard AJ, Slack MP. Epidemiology of invasive Haemophilus influenzae infections in England and Wales in the pre-vaccination era (1990-2). Epidemiol Infect 1995; 115:89-100. [PMID: 7641841 PMCID: PMC2271549 DOI: 10.1017/s0950268800058155] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
This survey defined the pattern of invasive Haemophilus influenzae infections during 1990-2 in six regions in England and Wales during the pre-vaccination era providing a baseline against which any changes in patterns of disease due to the introduction of the Haemophilus influenzae type b vaccination programme can be monitored. A total of 946 cases of invasive Haemophilus influenzae were recorded during the survey period of which almost 90% were due to type b and most of the remainder were non-typeable. Type b infections occurred predominantly in children less than 5 years of age (88%) with the highest attack rate in male infants in the 6-11 month age group. Diagnostic category varied with both age and serotype; meningitis was the commonest presentation overall but pneumonia and bacteraemia were more common in adults and non-typeable isolates. Mortality was highest in neonates and the elderly (over 65 years of age) who were more likely to have an underlying predisposing condition than older children and adults. Children under 5 years of age had a higher case fatality rate for non-typeable than for type b infections. Ampicillin resistance was 15% and there were no cefotaxime resistant type b isolates.
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Affiliation(s)
- E C Anderson
- Oxford Public Health Laboratory, Oxford Radcliffe Hospital
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35
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Mulholland EK, Byass P, Campbell H, Fritzell B, Greenwood AM, Todd J, Greenwood BM. The immunogenicity and safety of Haemophilus influenzae type b-tetanus toxoid conjugate vaccine in Gambian infants. ANNALS OF TROPICAL PAEDIATRICS 1994; 14:183-8. [PMID: 7825990 DOI: 10.1080/02724936.1994.11747715] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In developing countries, Haemophilus influenzae type b is a major cause of meningitis and pneumonia in the 1st year of life. The safety and immunogenicity of a Haemophilus influenzae type b polysaccharide-tetanus toxoid conjugate vaccine (PRP-T) were evaluated in two studies of Gambian infants. In the first study, 131 infants were recruited and randomized into three groups to receive PRP-T at 1 and 3 months (group A), PRP-T at 2 and 4 months (group B) or no PRP-T (group C). The liquid form of PRP-T was used. The geometric mean titre (GMT) of anti-PRP antibody 1 month after the second dose was 0.26 microgram/ml in group A and 0.41 microgram/ml in group B. In the second study, 66 infants were given PRP-T in the lyophilized form at 2, 3 and 4 months of age. The GMT 1 month after the first dose was 0.09 microgram/ml, after the second 0.74 microgram/ml and after the third 2.32 micrograms/ml. After the third dose, 72% of children had antibody levels greater than 1.0 microgram/ml and 93% greater than 0.15 microgram/ml. No serious side-effects were observed and the rate of adverse reactions was consistent with the concurrent administration of diphtheria-tetanus-pertussis (DPT) vaccine.
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Affiliation(s)
- E K Mulholland
- Medical Research Council Laboratories, Banjul, The Gambia
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Bedford H, Peckham C, Halket S, Hurley D, Harvey D, de Louvois J. National follow up of Haemophilus influenzae meningitis. Arch Dis Child 1993; 69:711-2. [PMID: 8285790 PMCID: PMC1029665 DOI: 10.1136/adc.69.6.711-b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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37
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Jordens JZ, Leaves NI, Anderson EC, Slack MP. Polymerase chain reaction-based strain characterization of noncapsulate Haemophilus influenzae. J Clin Microbiol 1993; 31:2981-7. [PMID: 8263183 PMCID: PMC266179 DOI: 10.1128/jcm.31.11.2981-2987.1993] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A polymerase chain reaction-based typing method for noncapsulate Haemophilus influenzae was developed. Randomly amplified polymorphic DNA fingerprints were generated from boiled supernatants prepared directly from bacterial colonies without the need for DNA extraction. The technique was applied to isolates obtained during putative outbreaks of chest infection and validated by comparison with sodium dodecyl sulfatepolyacrylamide gel electrophoresis analysis of outer membrane protein-enriched preparations and rRNA gene restriction analysis. There was complete concordance between the three techniques. The results show that randomly amplified polymorphic DNA analysis provides a highly discriminatory method of characterizing strains of noncapsulate H. influenzae which is eminently suitable as an epidemiological tool for the rapid investigation of outbreaks of infection.
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Affiliation(s)
- J Z Jordens
- Public Health Laboratory Service Haemophilus Reference Laboratory, University of Oxford, United Kingdom
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38
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Abstract
Haemophilus influenzae type b (Hib) is a major cause of serious bacterial infection in early childhood. In many developed countries it is the commonest cause of bacterial meningitis in children under 5 years of age. Serum antibodies to the polyribosylribitol phosphate (PRP) capsule, the main virulence factor of Hib, are protective, but the early vaccines containing purified PRP were poorly immunogenic in young children. However, 'second generation' protein conjugate vaccines have been shown to be immunogenic, effective and safe in young children. No serious adverse reactions to Hib vaccine have been reported to date. Clinically, the vaccine is indicated in the first few months of life and can be given at the same time as a primary course of diphtheria, pertussis and tetanus (DPT) immunisation. The vaccine should be given by deep subcutaneous or intramuscular injection. The only specific contraindication is a history of severe local reaction or a general reaction to previous Hib vaccination. Routine immunisation of infants under 6 months of age against Hib has become part of the regular primary schedule in many countries. In Finland this has resulted in a dramatic decline in Hib meningitis.
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Affiliation(s)
- Harry Campbell
- Fife Health Board, Glenrothes House, North Street, Glenrothes, Fife KY7 5PB, Scotland
| | - Harden Carter
- Consultant in Public Health Medicine, Forth Valley Health Board, Stirling, Scotland
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Booy R, Hodgson S, Griffiths H, Chapel HM, Moxon ER. Antibody persistence after accelerated immunisation against Haemophilus influenzae type b. BMJ (CLINICAL RESEARCH ED.) 1993; 306:971-2. [PMID: 8490473 PMCID: PMC1677465 DOI: 10.1136/bmj.306.6883.971] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- R Booy
- University Department of Paediatrics, John Radcliffe Hospital, Oxford
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40
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Falla TJ, Dobson SR, Crook DW, Kraak WA, Nichols WW, Anderson EC, Jordens JZ, Slack MP, Mayon-White D, Moxon ER. Population-based study of non-typable Haemophilus influenzae invasive disease in children and neonates. Lancet 1993; 341:851-4. [PMID: 8096561 DOI: 10.1016/0140-6736(93)93059-a] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The extent of non-capsulate, non-serotypable Haemophilus influenzae (NST) as a cause of serious invasive disease in children has not been fully defined. We describe the epidemiology of these childhood infections from cases identified during a continuing prospective survey of invasive H influenzae disease in the Oxford region, UK. 408 strains of H influenzae were isolated from cases of invasive disease. 383 (94%) were H influenzae type b (Hib), 24 (6%) were NST strains, and 1 was a type f strain. 3 of the NST strains were non-capsulate type b mutants (b-), but the remaining 21 strains were from the phylogenetically distinct and heterogeneous population of non-capsulate H influenzae (NC). 10 of the NC strains were isolated from neonates with sepsis; crude mortality rate was 40%, with an incidence of 4.6 cases per 100,000 livebirths. 11 NC strains were isolated from children after the neonatal period and under 10 years of age, 4 (36%) of which had severe, unrelated, predisposing conditions. The incidence of NC invasive diseases in these children was 0.5 per 100,000 per year. The attributable mortality for these infections was 10%. Infections due to these H influenzae strains are, after the implementation of Hib vaccines, likely to persist and represent a substantial proportion of the serious infections caused by this species.
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Affiliation(s)
- T J Falla
- Public Health Laboratory, John Radcliffe Hospital, Headington, Oxford, UK
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41
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Affiliation(s)
- B L Priestley
- Sheffield Children's Hospital NHS Trust, Western Bank, UK
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Agbarakwe AE, Misbah SA, Griffiths H, Chapel HM. Effect of beta propiolactone on specific antibody measurements by ELISA. J Clin Pathol 1993; 46:368-9. [PMID: 8496395 PMCID: PMC501222 DOI: 10.1136/jcp.46.4.368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Serum samples from 30 HIV seronegative patients were treated with beta propiolactone (BPL) to determine whether BPL interfaces with ELISA for specific antibodies against protein and carbohydrate antigens. BPL had no discernible effect on specific antibody measurements by ELISA. With the measuring need for specific antibody measurements in the management of HIV seropositive patients, it is reassuring that this laboratory safety measure does not impair the reliability of results.
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Affiliation(s)
- A E Agbarakwe
- Department of Immunology, John Radcliffe Hospital, Oxford
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43
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Affiliation(s)
- S P Conway
- Department of Infectious Diseases, Seacroft Hospital, University Department of Paediatrics, St James's University Hospital, Leeds, England
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Johnson AW, Mokuolu OA, Onile BA. Chloramphenicol-resistant Haemophilus influenzae meningitis in young urban Nigerian children. Acta Paediatr 1992; 81:941-3. [PMID: 1467621 DOI: 10.1111/j.1651-2227.1992.tb12143.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In a developing country like Nigeria, the unusual emergence of Haemophilus influenzae type b, resistant to cost-effective antimicrobials, is of serious concern. We report three cases of H. influenzae type b meningitis in young Nigerian children in whom clinical and bacteriological features of resistance to chloramphenicol were identified. One of the cases had concomitant resistance to ampicillin (multiple-drug resistance). Significant anaemia was an associated feature in two cases, one of whom had a recent measles infection. All three cases were malnourished. The possible mechanisms of antimicrobial resistance in H. influenzae infections are highlighted while the need for periodic surveillance of antibiotic resistance profiles in resource-poor countries is emphasized. The potential value of prophylactic measures like H. influenzae type b conjugate immunization is discussed.
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Affiliation(s)
- A W Johnson
- Department of Paediatrics/Child Health, University of Ilorin Teaching Hospital, Nigeria
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45
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Fritzell B, Plotkin S. Efficacy and safety of a Haemophilus influenzae type b capsular polysaccharide-tetanus protein conjugate vaccine. J Pediatr 1992; 121:355-62. [PMID: 1517908 DOI: 10.1016/s0022-3476(05)81786-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A polyribosylribitol phosphate (polysaccharide)-tetanus protein conjugate vaccine (PRP-T) against Haemophilus influenzae type b (Hib) was evaluated for safety and efficacy after vaccination of more than 100,000 infants. No major side effects were attributed to the vaccine. Immunogenicity studies showed an antibody response in 70% to 100% of infants after two doses, and in 98% to 100% of infants after three doses, within the first 6 months of life. Antibodies persisted in 90% of recipients, in whom significant anamnestic responses developed after a booster dose at 18 months of age. In comparison with other available Hib vaccines, PRP-T induces equal or higher mean titers after three doses. Although licensure of other vaccines interrupted controlled efficacy trials, up to that point five cases of Hib disease in those trials had occurred in placebo recipients, and no Hib disease has been reported in the more than 100,000 vaccinated infants who have received more than one dose of PRP-T. Thus PRP-T combined immunogenicity early in life with induction of immunologic memory.
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Affiliation(s)
- B Fritzell
- Connaught Laboratories, Swiftwater, Pennsylvania 18370
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