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Rozenbaum MH, Chilson E, Farkouh R, Huang L, Cane A, Arguedas A, Tort MJ, Snow V, Averin A, Weycker D, Hariharan D, Atwood M. Cost-Effectiveness of 20-Valent Pneumococcal Conjugate Vaccine Among US Children with Underlying Medical Conditions. Infect Dis Ther 2024; 13:745-760. [PMID: 38491269 PMCID: PMC11058137 DOI: 10.1007/s40121-024-00944-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 02/15/2024] [Indexed: 03/18/2024] Open
Abstract
INTRODUCTION A 20-valent pneumococcal conjugate vaccine (PCV20) was recently recommended for use among US children. We evaluated the cost-effectiveness of PCV20 among children aged 6 years with chronic medical conditions (CMC+) and children aged 6 years with immunocompromising conditions (IC) versus one and two doses of 23-valent pneumococcal polysaccharide vaccine (PPSV23), respectively. METHODS A probabilistic model was employed to depict 10-year risk of clinical outcomes and economic costs of pneumococcal disease, reduction in life years from premature death, and expected impact of vaccination among one cohort of children with CMC+ and IC aged 6 years. Vaccine uptake was assumed to be 20% for both PCV20 and PPSV23. Cost per quality-adjusted life year (QALY) gained was evaluated from the US societal and healthcare system perspectives; deterministic and probabilistic sensitivity analyses (DSA/PSA) were also conducted. RESULTS Among the 226,817 children with CMC+ aged 6 years in the US, use of PCV20 (in lieu of PPSV23) was projected to reduce the number cases of pneumococcal disease by 5203 cases, medical costs by US$8.7 million, and nonmedical costs by US$6.2 million. PCV20 was the dominant strategy versus PPSV23 from both the healthcare and societal perspectives. In the PSA, 99.9% of the 1000 simulations yielded a finding of dominance for PCV20. Findings in analyses of children with IC aged 6 years in the USA were comparable (i.e., PCV20 was the dominant vaccination strategy). Scenario analyses showed that increasing PCV20 uptake to 100% could potentially prevent > 22,000 additional cases of pneumococcal disease and further reduce medical and nonmedical costs by US$70.0 million among children with CMC+ and IC. CONCLUSIONS Use of PCV20 among young children with CMC+ and IC in the USA would reduce the clinical burden of pneumococcal disease and yield overall cost savings from both the US healthcare system and societal perspectives. Higher PCV20 uptake could further reduce the number of pneumococcal disease cases in this population.
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Affiliation(s)
- Mark H Rozenbaum
- Value and Evidence Team, Pneumococcal Vaccines, Pfizer Inc., Capelle a/d Ijssel, The Netherlands.
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Johnson CN, Wilde S, Tuomanen E, Rosch JW. Convergent impact of vaccination and antibiotic pressures on pneumococcal populations. Cell Chem Biol 2024; 31:195-206. [PMID: 38052216 PMCID: PMC10938186 DOI: 10.1016/j.chembiol.2023.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 09/08/2023] [Accepted: 11/07/2023] [Indexed: 12/07/2023]
Abstract
Streptococcus pneumoniae is a remarkably adaptable and successful human pathogen, playing dual roles of both asymptomatic carriage in the nasopharynx and invasive disease including pneumonia, bacteremia, and meningitis. Efficacious vaccines and effective antibiotic therapies are critical to mitigating morbidity and mortality. However, clinical interventions can be rapidly circumvented by the pneumococcus by its inherent proclivity for genetic exchange. This leads to an underappreciated interplay between vaccine and antibiotic pressures on pneumococcal populations. Circulating populations have undergone dramatic shifts due to the introduction of capsule-based vaccines of increasing valency imparting strong selective pressures. These alterations in population structure have concurrent consequences on the frequency of antibiotic resistance profiles in the population. This review will discuss the interactions of these two selective forces. Understanding and forecasting the drivers of antibiotic resistance and capsule switching are of critical importance for public health, particularly for such a genetically promiscuous pathogen as S. pneumoniae.
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Affiliation(s)
- Cydney N Johnson
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shyra Wilde
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Elaine Tuomanen
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Jason W Rosch
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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Feng S, McLellan J, Pidduck N, Roberts N, Higgins JP, Choi Y, Izu A, Jit M, Madhi SA, Mulholland K, Pollard AJ, Temple B, Voysey M. Immunogenicity and seroefficacy of 10-valent and 13-valent pneumococcal conjugate vaccines: a systematic review and network meta-analysis of individual participant data. EClinicalMedicine 2023; 61:102073. [PMID: 37425373 PMCID: PMC10328810 DOI: 10.1016/j.eclinm.2023.102073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 07/11/2023] Open
Abstract
Background Vaccination of infants with pneumococcal conjugate vaccines (PCV) is recommended by the World Health Organization. Evidence is mixed regarding the differences in immunogenicity and efficacy of the different pneumococcal vaccines. Methods In this systematic-review and network meta-analysis, we searched the Cochrane Library, Embase, Global Health, Medline, clinicaltrials.gov and trialsearch.who.int up to February 17, 2023 with no language restrictions. Studies were eligible if they presented data comparing the immunogenicity of either PCV7, PCV10 or PCV13 in head-to-head randomised trials of young children under 2 years of age, and provided immunogenicity data for at least one time point after the primary vaccination series or the booster dose. Publication bias was assessed via Cochrane's Risk Of Bias due to Missing Evidence tool and comparison-adjusted funnel plots with Egger's test. Individual participant level data were requested from publication authors and/or relevant vaccine manufacturers. Outcomes included the geometric mean ratio (GMR) of serotype-specific IgG and the relative risk (RR) of seroinfection. Seroinfection was defined for each individual as a rise in antibody between the post-primary vaccination series time point and the booster dose, evidence of presumed subclinical infection. Seroefficacy was defined as the RR of seroinfection. We also estimated the relationship between the GMR of IgG one month after priming and the RR of seroinfection by the time of the booster dose. The protocol is registered with PROSPERO, ID CRD42019124580. Findings 47 studies were eligible from 38 countries across six continents. 28 and 12 studies with data available were included in immunogenicity and seroefficacy analyses, respectively. GMRs comparing PCV13 vs PCV10 favoured PCV13 for serotypes 4, 9V, and 23F at 1 month after primary vaccination series, with 1.14- to 1.54- fold significantly higher IgG responses with PCV13. Risk of seroinfection prior to the time of booster dose was lower for PCV13 for serotype 4, 6B, 9V, 18C and 23F than for PCV10. Significant heterogeneity and inconsistency were present for most serotypes and for both outcomes. Two-fold higher antibody after primary vaccination was associated with a 54% decrease in risk of seroinfection (RR 0.46, 95% CI 0.23-0.96). Interpretation Serotype-specific differences were found in immunogenicity and seroefficacy between PCV13 and PCV10. Higher antibody response after vaccination was associated with a lower risk of subsequent infection. These findings could be used to compare PCVs and optimise vaccination strategies. Funding The NIHR Health Technology Assessment Programme.
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Affiliation(s)
- Shuo Feng
- Department of Paediatrics, Oxford Vaccine Group, University of Oxford, Oxford, UK
| | - Julie McLellan
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Nicola Pidduck
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Nia Roberts
- Bodleian Health Care Libraries, University of Oxford, Oxford, UK
| | - Julian P.T. Higgins
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Yoon Choi
- Modelling and Economics Unit, UK Health Security Agency, London, UK
| | - Alane Izu
- South African Medical Research Council MRC Vaccines and Infectious Diseases Analytics Research Unit, Infectious Diseases and Oncology Research Institute, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Mark Jit
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Shabir A. Madhi
- South African Medical Research Council MRC Vaccines and Infectious Diseases Analytics Research Unit, Infectious Diseases and Oncology Research Institute, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Wits Infectious Diseases and Oncology Research Institute, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Kim Mulholland
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- Murdoch Children's Research Institute, Melbourne, VIC, Australia
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Andrew J. Pollard
- Department of Paediatrics, Oxford Vaccine Group, University of Oxford, Oxford, UK
- NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Beth Temple
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- Murdoch Children's Research Institute, Melbourne, VIC, Australia
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Merryn Voysey
- Department of Paediatrics, Oxford Vaccine Group, University of Oxford, Oxford, UK
- NIHR Oxford Biomedical Research Centre, Oxford, UK
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Musher DM, Anderson R, Feldman C. The remarkable history of pneumococcal vaccination: an ongoing challenge. Pneumonia (Nathan) 2022; 14:5. [PMID: 36153636 PMCID: PMC9509586 DOI: 10.1186/s41479-022-00097-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/22/2022] [Indexed: 11/21/2022] Open
Abstract
Although it varies with age and geographical distribution, the global burden of infection with Streptococcus pneumoniae (pneumococcus) remains considerable. The elderly, and younger adults with comorbid conditions, are at particularly high risk of pneumococcal infection, and this risk will increase as the population ages. Vaccination should be the backbone of our current strategies to deal with this infection. Main body: This manuscript reviews the history of the development of pneumococcal vaccines, and the impact of different vaccines and vaccination strategies over the past 111 years. It documents the early years of vaccine development in the gold mines of South Africa, when vaccination with killed pneumococci was shown to be effective, even before the recognition that different pneumococci were antigenically distinct. The development of type-specific vaccines, still with whole killed pneumococci, showed a high degree of efficacy. The identification of the importance of the pneumococcal capsule heralded the era of vaccination with capsular polysaccharides, although with the advent of penicillin, interest in pneumococcal vaccine development waned. The efforts of Austrian and his colleagues, who documented that despite penicillin therapy, patients still died from pneumococcal infection in the first 96 h, ultimately led to the licensing first of a 14-valent pneumococcal polysaccharide in 1977 followed by the 23-valent pneumococcal polysaccharide in 1983. The principal problem with these, as with other polysaccharide vaccines, was that that they failed to immunize infants and toddlers, who were at highest risk for pneumococcal disease. This was overcome by chemical linking or conjugation of the polysaccharide molecules to an immunogenic carrier protein. Thus began the era of pneumococcal conjugate vaccine (PCV), starting with PCV7, progressing to PCV10 and PCV13, and, most recently, PCV15 and PCV20. However, these vaccines remain serotype specific, posing the challenge of new serotypes replacing vaccine types. Current research addresses serotype-independent vaccines which, so far, has been a challenging and elusive endeavor. Conclusion: While there has been enormous progress in the development of pneumococcal vaccines during the past century, attempts to develop a vaccine that will retain its efficacy for most pneumococcal serotypes are ongoing.
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Abstract
Polysaccharides are often the most abundant antigens found on the extracellular surfaces of bacterial cells. These polysaccharides play key roles in interactions with the outside world, and for many bacterial pathogens, they represent what is presented to the human immune system. As a result, many vaccines have been or currently are being developed against carbohydrate antigens. In this review, we explore the diversity of capsular polysaccharides (CPS) in Salmonella and other selected bacterial species and explain the classification and function of CPS as vaccine antigens. Despite many vaccines being developed using carbohydrate antigens, the low immunogenicity and the diversity of infecting strains and serovars present an antigen formulation challenge to manufacturers. Vaccines tend to focus on common serovars or have changing formulations over time, reflecting the trends in human infection, which can be costly and time-consuming. We summarize the approaches to generate carbohydrate-based vaccines for Salmonella, describe vaccines that are in development and emphasize the need for an effective vaccine against non-typhoidal Salmonella strains.
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The Pneumococcal Polysaccharide-Tetanus Toxin Native C-Fragment Conjugate Vaccine: The Carrier Effect and Immunogenicity. Mediators Inflamm 2020; 2020:9596129. [PMID: 32714092 PMCID: PMC7355367 DOI: 10.1155/2020/9596129] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 06/15/2020] [Indexed: 11/18/2022] Open
Abstract
The encapsulated bacteria, as Streptococcus pneumonia, Haemophilus influenzae type b, and Neisseria meningitidis, cause serious morbidity and mortality worldwide. The capsular polysaccharide (PS), which could elicit a weak T cell-independent immune response, is a vital virulence determinant. One of the strategies to improve the PS-specific immunogenicity is to conjugate PS with a nontoxic carrier protein. Tetanus toxoid (TT) and CRM197 are the typical carrier proteins for the PS conjugate vaccines. TT is the inactivated tetanus toxin manipulated with formaldehyde, which suffers from the pollution from residual formaldehyde and the incomplete detoxification. CRM197 has the disadvantage of low-yield purification with the requirement of sophisticated culture conditions. Thus, a novel carrier protein without these disadvantages is highly required. The tetanus toxin native C-fragment (Hc) is safe, low-cost, and highly immunogenic with easy purification, which can act as a promising carrier protein. Pneumococcal serogroups 14 and 23F were major epidemic causes of pneumococcal infections. In the present study, the capsular PSs (PS14 and PS23F) were conjugated with Hc, TT, and CRM197, respectively. TT- and CRM197-based conjugates acted as controls for Hc-based conjugates (PS14-Hc and PS23F-Hc). The structural properties of Hc were not fundamentally changed after conjugated with PS. PS14-Hc and PS23F-Hc could potentiate sound PS-specific antibody levels comparable to the controls. Thus, Hc exhibited a practical carrier effect to help the pneumococcal conjugate vaccines perform good immunogenicities.
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7
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Tin Tin Htar M, Sings HL, Syrochkina M, Taysi B, Hilton B, Schmitt HJ, Gessner BD, Jodar L. The impact of pneumococcal conjugate vaccines on serotype 19A nasopharyngeal carriage. Expert Rev Vaccines 2019; 18:1243-1270. [DOI: 10.1080/14760584.2019.1675521] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
| | - Heather L. Sings
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Maria Syrochkina
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Moscow, Russia
| | - Bulent Taysi
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Istanbul, Turkey
| | - Betsy Hilton
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Heinz-Josef Schmitt
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Bradford D. Gessner
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Luis Jodar
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
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Briles DE, Paton JC, Mukerji R, Swiatlo E, Crain MJ. Pneumococcal Vaccines. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0028-2018. [PMID: 31858954 PMCID: PMC10921951 DOI: 10.1128/microbiolspec.gpp3-0028-2018] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Indexed: 01/14/2023] Open
Abstract
Streptococcus pneumoniae is a Gram-Positive pathogen that is a major causative agent of pneumonia, otitis media, sepsis and meningitis across the world. The World Health Organization estimates that globally over 500,000 children are killed each year by this pathogen. Vaccines offer the best protection against S. pneumoniae infections. The current polysaccharide conjugate vaccines have been very effective in reducing rates of invasive pneumococcal disease caused by vaccine type strains. However, the effectiveness of these vaccines have been somewhat diminished by the increasing numbers of cases of invasive disease caused by non-vaccine type strains, a phenomenon known as serotype replacement. Since, there are currently at least 98 known serotypes of S. pneumoniae, it may become cumbersome and expensive to add many additional serotypes to the current 13-valent vaccine, to circumvent the effect of serotype replacement. Hence, alternative serotype independent strategies, such as vaccination with highly cross-reactive pneumococcal protein antigens, should continue to be investigated to address this problem. This chapter provides a comprehensive discussion of pneumococcal vaccines past and present, protein antigens that are currently under investigation as vaccine candidates, and other alternatives, such as the pneumococcal whole cell vaccine, that may be successful in reducing current rates of disease caused by S. pneumoniae.
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Affiliation(s)
- D E Briles
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - J C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide, 5005, Australia
| | - R Mukerji
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - E Swiatlo
- Section of Infectious Diseases, Southeast Louisiana Veterans Health Care System, New Orleans, LA
| | - M J Crain
- Department of Pediatrics and Microbiology, University of Alabama at Birmingham
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Coughtrie AL, Jefferies JM, Cleary DW, Doncaster CP, Faust SN, Kraaijeveld AR, Moore MV, Mullee MA, Roderick PJ, Webb JS, Yuen HM, Clarke SC. Microbial epidemiology and carriage studies for the evaluation of vaccines. J Med Microbiol 2019; 68:1408-1418. [DOI: 10.1099/jmm.0.001046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Affiliation(s)
- Abigail L. Coughtrie
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Johanna M. Jefferies
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - David W. Cleary
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | | | - Saul N. Faust
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Clinical Research Facility, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | | | - Michael V. Moore
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Mark A. Mullee
- NIHR Research Design Service South Central, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Paul J. Roderick
- Global Health Research Institute, University of Southampton, Southampton, UK
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Jeremy S. Webb
- Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Ho Ming Yuen
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Stuart C. Clarke
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- Global Health Research Institute, University of Southampton, Southampton, UK
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10
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Lee YJ, Huang YT, Kim SJ, Kerpelev M, Gonzalez V, Kaltsas A, Papanicolaou G. Trends in Invasive Pneumococcal Disease in Cancer Patients After the Introduction of 7-valent Pneumococcal Conjugate Vaccine: A 20-year Longitudinal Study at a Major Urban Cancer Center. Clin Infect Dis 2019; 66:244-253. [PMID: 29020313 DOI: 10.1093/cid/cix739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 08/11/2017] [Indexed: 12/11/2022] Open
Abstract
Background Rates of invasive pneumococcal disease (IPD) declined since routine childhood immunization with the 7-valent pneumococcal conjugate vaccine (PCV7) in 2000. We studied the impact of PCV7 on the incidence of IPD in cancer patients. Methods This was a retrospective analysis of adult and pediatric patients treated at Memorial Sloan Kettering Cancer Center from 1992 to 2012. Recovery of Streptococcus pneumoniae from a sterile site defined IPD. IPD incidence was calculated as cases per 1,000 unique patient-visits per year (UPV). IPD incidence was calculated for the periods: "before PCV7" (1992-2000), "after PCV7" (2001-2010) and "after PCV13" (2011-2012). Results Of 343 IPD cases, 165, 155, and 23 cases occurred "before PCV7," "after PCV7" and "after PCV13" respectively. The IPD incidence declined from 0.43 "before PCV7" to 0.17 "after PCV7" (95% confidence interval [CI]: 0.33-0.46, P < .001) and 0.11 "after PCV13" (95% CI: 0.42-0.96, P = .004). Adults with hematologic malignancies and children had the highest incidence. In patients 1-4 years old, the incidence declined from 11.2 "before PCV7" to 2.38 "after PCV7" (79% decrease, 95% CI: 0.1-0.4, P < .001). In patients with hematologic malignancies, the incidence declined from 2.55 "before PCV7" to 0.92 "after PCV7" (64% decrease, 95% CI: 0.27-0.47, P < .001). Conclusions The incidence of IPD among cancer patients sharply declined after introduction of PCV7; especially in high risk groups. The decline in adults suggests an indirect effect from PCV7 childhood vaccination.
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Affiliation(s)
- Yeon Joo Lee
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York.,Department of Medicine, Weill Cornell Medical College, Cornell University, New York
| | - Yao-Ting Huang
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York
| | - Seong Jin Kim
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York
| | - Marina Kerpelev
- Information Systems, Memorial Sloan Kettering Cancer Center, New York
| | - Victoria Gonzalez
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York
| | - Anna Kaltsas
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York.,Department of Medicine, Weill Cornell Medical College, Cornell University, New York
| | - Genovefa Papanicolaou
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York.,Department of Medicine, Weill Cornell Medical College, Cornell University, New York
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Dagan R. Relationship between immune response to pneumococcal conjugate vaccines in infants and indirect protection after vaccine implementation. Expert Rev Vaccines 2019; 18:641-661. [PMID: 31230486 DOI: 10.1080/14760584.2019.1627207] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Introduction: Streptococcus pneumoniae is a leading cause of morbidity and mortality worldwide. Widespread infant vaccination with pneumococcal conjugate vaccines (PCVs) substantially reduced vaccine-serotype pneumococcal disease by direct protection of immunized children and indirect protection of the community via decreased nasopharyngeal carriage and transmission. Essential to grasping the public health implications of pediatric PCV immunization is an understanding of how PCV formulations impact carriage. Areas covered: Using clinical evidence, this review examines how the immune response to PCVs is associated with subsequent nasopharyngeal carriage reduction in vaccinated infants and toddlers. By combining direct and indirect protection, carriage reduction results in a reduced spread of vaccine serotypes, and eventually, a decrease in vaccine serotype disease incidence in community members of all ages. Expert opinion: The current review presents some of the aspects that influence the overall impact of PCVs on vaccine-serotype carriage, and thus, spread. The link between reduction of vaccine-serotype carriage and the eventual reduction of vaccine-serotype disease in the wider community is described by comparing data from current PCVs, specifically with respect to their ability to reduce carriage of some cross-reacting serotypes (i.e. 6A versus 6B and 19A versus 19F).
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Affiliation(s)
- Ron Dagan
- a The Faculty of Health Sciences , Ben-Gurion University of the Negev , Beer-Sheva , Israel
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12
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Marshall HS, McMillan M, Koehler A, Lawrence A, MacLennan J, Maiden M, Ramsay M, Ladhani SN, Trotter C, Borrow R, Finn A, Sullivan T, Richmond P, Kahler C, Whelan J, Vadivelu K. B Part of It School Leaver protocol: an observational repeat cross-sectional study to assess the impact of a meningococcal serogroup B (4CMenB) vaccine programme on carriage of Neisseria meningitidis. BMJ Open 2019; 9:e027233. [PMID: 31064808 PMCID: PMC6528050 DOI: 10.1136/bmjopen-2018-027233] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Invasive meningococcal disease is uncommon but associated with a high-case fatality rate. Carriage prevalence of the causative bacteria, Neisseria meningitidis, is high in adolescents. A large (n=34 500) cluster randomised controlled trial (RCT) to assess the impact of a meningococcal B (MenB) vaccine on meningococcal carriage was implemented in the state of South Australia (SA) for year 10, 11 and 12 senior school students in 2017-2018. This study will assess the impact of MenB vaccine (4CMenB) on carriage prevalence in school leavers in SA, 1 and 2 years after implementation of the cluster RCT in adolescents. Measuring the impact of population programmes on carriage can assist in informing future meningococcal immunisation programmes such as targeted age groups and use of catch-up campaigns. METHODS AND ANALYSIS This repeat cross-sectional study will assess carriage prevalence in 2018 and 2019. All school leavers who attended year 12 in any school in SA in 2018 or 2019 will be invited to participate in this study. An oropharyngeal swab will be taken from each participating student and a risk factor questionnaire completed by the student following informed consent. Students will attend clinics at SA universities, technical colleges, and metropolitan, rural and remote government council clinics. Confirmed vaccination history will allow a comparison in carriage prevalence between vaccinated and unvaccinated school leavers. A sample size of 4096 students per year will provide 80% power to detect a 20% difference in carriage prevalence of disease-causing meningococci (defined as genogroup A, B, C, W, X or Y) between years. ETHICS AND DISSEMINATION The study was approved by the Women's and Children's Health Network Human Research Ethics Committee. Results will be published in international peer review journals and presented at national and international conferences. TRIAL REGISTRATION NUMBER NCT03419533; Pre-results.
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Affiliation(s)
- Helen S Marshall
- Vaccinology and Immunology Research Trials Unit, Women's and Children's Health Network, North Adelaide, South Australia, Australia
- Robinson Research Institute and Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Mark McMillan
- Vaccinology and Immunology Research Trials Unit, Women's and Children's Health Network, North Adelaide, South Australia, Australia
- Robinson Research Institute and Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Ann Koehler
- Communicable Disease Control Branch, SA Health, Adelaide, South Australia, Australia
| | - Andrew Lawrence
- Microbiology Department, SA Pathology, Adelaide, South Australia, Australia
| | | | - Martin Maiden
- Department of Zoology, University of Oxford, Oxford, UK
| | - Mary Ramsay
- Immunisation Department, Public Health England, London, UK
| | | | - Caroline Trotter
- Immunisation Department, Public Health England, London, UK
- Department of Veterinary Medicine, University of Cambridge, Bristol, UK
| | - Ray Borrow
- Meningococcal Reference Unit, Public Health England, Manchester, UK
| | - Adam Finn
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Thomas Sullivan
- School of Public Health, The University of Adelaide, Adelaide, South Australia, Australia
| | - Peter Richmond
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Institute for Child Health Research, University of Western Australia, Perth, Western Australia, Australia
| | - Charlene Kahler
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Science, University of Western Australia, Perth, Western Australia, Australia
| | - Jane Whelan
- GlaxoSmithKline Vaccines, Amsterdam, Netherlands
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13
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Weinberger DM, Pitzer VE, Regev-Yochay G, Givon-Lavi N, Dagan R. Association Between the Decline in Pneumococcal Disease in Unimmunized Adults and Vaccine-Derived Protection Against Colonization in Toddlers and Preschool-Aged Children. Am J Epidemiol 2019; 188:160-168. [PMID: 30462150 PMCID: PMC6321804 DOI: 10.1093/aje/kwy219] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 09/21/2018] [Indexed: 01/01/2023] Open
Abstract
Vaccinating children with pneumococcal conjugate vaccine (PCV) disrupts transmission, reducing disease rates in unvaccinated adults. When considering changes in vaccine dosing strategies (e.g., removing doses), it is critical to understand which groups of children contribute most to transmission to adults. We used data from Israel (2009–2016) to evaluate how the buildup of vaccine-associated immunity in children was associated with declines in invasive pneumococcal disease (IPD) due to vaccine-targeted serotypes in unimmunized adults. Data on vaccine uptake and prevalence of colonization with PCV-targeted serotypes were obtained from children visiting an emergency department in southern Israel and from surveys of colonization from central Israel. Data on IPD in adults were obtained from a nationwide surveillance study carried out in Israel. We compared the trajectory of decline of IPD due to PCV-targeted serotypes in adults with the decline of colonization prevalence and increase in vaccine-derived protection against pneumococcal carriage among different age groupings of children. The declines in IPD in adults were most closely associated with the declines in colonization and increased vaccination coverage among children in the age range of 36–59 months. This suggests that preschool-aged children, rather than infants, are responsible for maintaining the indirect benefits of PCVs.
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Affiliation(s)
- Daniel M Weinberger
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut
| | - Virginia E Pitzer
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut
| | - Gili Regev-Yochay
- Infection Prevention and Control Unit, Sheba Medical Center, Ramat Gan, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Noga Givon-Lavi
- Pediatric Infectious Diseases Unit, Soroka University Medical Center, Be’er Sheva, Israel
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Be’er Sheva, Israel
| | - Ron Dagan
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Be’er Sheva, Israel
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14
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Croucher NJ, Løchen A, Bentley SD. Pneumococcal Vaccines: Host Interactions, Population Dynamics, and Design Principles. Annu Rev Microbiol 2018; 72:521-549. [DOI: 10.1146/annurev-micro-090817-062338] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Streptococcus pneumoniae (the pneumococcus) is a nasopharyngeal commensal and respiratory pathogen. Most isolates express a capsule, the species-wide diversity of which has been immunologically classified into ∼100 serotypes. Capsule polysaccharides have been combined into multivalent vaccines widely used in adults, but the T cell independence of the antibody response means they are not protective in infants. Polysaccharide conjugate vaccines (PCVs) trigger a T cell–dependent response through attaching a carrier protein to capsular polysaccharides. The immune response stimulated by PCVs in infants inhibits carriage of vaccine serotypes (VTs), resulting in population-wide herd immunity. These were replaced in carriage by non-VTs. Nevertheless, PCVs drove reductions in infant pneumococcal disease, due to the lower mean invasiveness of the postvaccination bacterial population; age-varying serotype invasiveness resulted in a smaller reduction in adult disease. Alternative vaccines being tested in trials are designed to provide species-wide protection through stimulating innate and cellular immune responses, alongside antibodies to conserved antigens.
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Affiliation(s)
- Nicholas J. Croucher
- Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, United Kingdom
| | - Alessandra Løchen
- Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, United Kingdom
| | - Stephen D. Bentley
- Infection Genomics Programme, Wellcome Sanger Institute, Hinxton, Cambridge CB10 1SA, United Kingdom
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15
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Balasubramanian R, Im J, Lee JS, Jeon HJ, Mogeni OD, Kim JH, Rakotozandrindrainy R, Baker S, Marks F. The global burden and epidemiology of invasive non-typhoidal Salmonella infections. Hum Vaccin Immunother 2018; 15:1421-1426. [PMID: 30081708 PMCID: PMC6663144 DOI: 10.1080/21645515.2018.1504717] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Invasive non-typhoidal Salmonella (iNTS) disease has emerged as a major public health concern. Yet, understanding of the global burden is incomplete, limited particularly by the breadth of blood culture-based surveillance systems that are able to accurately diagnose the etiology of bacteremia. The accessibility of whole genome sequencing has allowed for genetic characterization of pathogens, shedding light on its evolutionary history and sounding alerts for its future progression. iNTS disease is observed to be a particular threat in sub-Saharan Africa, with a case fatality rate greatly exceeding that of typhoid fever, and commonly affecting infants, young children and immunocompromised adults. While iNTS disease might also be a threat in Asia and Latin America, its burden is not well characterized, primarily owing to the lack of comprehensive reporting in these regions. Drug-resistant Salmonella enterica (S. enterica) serovars (e.g. Typhimurium sequence type 313 (ST313)) have emerged as a potential consequence of sustained antibiotic pressure. Genetic analyses have identified distinguished iNTS disease-causing strains that are particularly virulent in certain human host populations. Effective treatment strategies, including vaccination, are necessary; iNTS vaccines targeting the most common S. enterica serovars, Typhimurium, Enteritidis and Dublin, are currently in early developmental stages. Funding and political support is needed to promote vaccine development and implementation programs to ultimately reduce the threat of iNTS disease in high risk areas.
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Affiliation(s)
| | - Justin Im
- b International Vaccine Institute , Seoul , Republic of Korea
| | - Jung-Seok Lee
- b International Vaccine Institute , Seoul , Republic of Korea
| | - Hyon Jin Jeon
- b International Vaccine Institute , Seoul , Republic of Korea
| | - Ondari D Mogeni
- b International Vaccine Institute , Seoul , Republic of Korea
| | - Jerome H Kim
- b International Vaccine Institute , Seoul , Republic of Korea
| | | | - Stephen Baker
- d The Department of Medicine , University of Cambridge , Cambridge , United Kingdom.,e Oxford University Clinical Research Unit , Ho Chi Minh City , Vietnam
| | - Florian Marks
- b International Vaccine Institute , Seoul , Republic of Korea.,d The Department of Medicine , University of Cambridge , Cambridge , United Kingdom
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16
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Li J, Shao Z, Liu G, Bai X, Borrow R, Chen M, Guo Q, Han Y, Li Y, Taha MK, Xu X, Xu X, Zheng H. Meningococcal disease and control in China: Findings and updates from the Global Meningococcal Initiative (GMI). J Infect 2018; 76:429-437. [PMID: 29406154 DOI: 10.1016/j.jinf.2018.01.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/22/2017] [Accepted: 01/03/2018] [Indexed: 10/18/2022]
Abstract
The Global Meningococcal Initiative (GMI) is a global expert group, including scientists, clinicians and public health officials from a wide range of specialities. The goal of the GMI is to prevent meningococcal disease worldwide through education, research, and co-operation. The Chinese GMI roundtable meeting was held in June 2017. The GMI met with local experts to gain insight into the meningococcal disease burden in China and current prevention and vaccination strategies in place. China experienced five epidemics of serogroup A meningococcal disease (MenA) between 1938 and 1977, with peak incidence of 403/100,000 recorded in 1967. MenA incidence rates have significantly declined following the universal introduction of the MenA polysaccharide vaccine in China in the 1980s. Further, surveillance data indicates changing meningococcal epidemiology in China with the emergence of new clones of serogroup B from serogroup C clonal complex (cc) 4821 due to capsular switching, and the international spread of serogroup W cc11. The importance of carriage and herd protection for controlling meningococcal disease was highlighted with the view to introduce conjugate vaccines and serogroup B vaccines into the national immunization schedule. Improved disease surveillance and standardized laboratory techniques across and within provinces will ensure optimal epidemiological monitoring.
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Affiliation(s)
- Junhong Li
- National Immunisation Programme Department, Chinese Center for Disease Control and Prevention, Beijing, China.
| | - Zhujun Shao
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
| | - Gang Liu
- Department of Infectious Disease, Beijing Children's Hospital, Beijing, China.
| | - Xilian Bai
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, UK.
| | - Ray Borrow
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, UK.
| | - Min Chen
- Department of Microbiology, Center for Disease Control and Prevention, Shanghai, China.
| | - Qinglan Guo
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China.
| | - Yue Han
- Department of Immunology, Center for Disease Control and Prevention, Liaoning, China.
| | - Yixing Li
- National Immunisation Programme Department, Chinese Center for Disease Control and Prevention, Beijing, China.
| | - Muhamed-Kheir Taha
- National Reference Centre for Meningococci, Institute Pasteur, Paris, France.
| | - Xihai Xu
- Department of Infectious Diseases, the First Affiliated Hospital of Anhui Medical University, China.
| | - Xin Xu
- Department of Immunization Programme, Center for Disease Control and Prevention, Guangdong, China.
| | - Huizhen Zheng
- Department of Immunization Programme, Center for Disease Control and Prevention, Guangdong, China.
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17
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Breakwell L, Whaley M, Khan UI, Bandy U, Alexander-Scott N, Dupont L, Vanner C, Chang HY, Vuong JT, Martin S, MacNeil JR, Wang X, Meyer SA. Meningococcal carriage among a university student population - United States, 2015. Vaccine 2017; 36:29-35. [PMID: 29183735 DOI: 10.1016/j.vaccine.2017.11.040] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 11/06/2017] [Accepted: 11/15/2017] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Several outbreaks of serogroup B meningococcal disease have occurred among university students in recent years. In the setting of high coverage of the quadrivalent meningococcal conjugate vaccine and prior to widespread use of serogroup B meningococcal vaccines among adolescents, we conducted surveys to characterize the prevalence and molecular characteristics of meningococcal carriage among university students. METHODS Two cross-sectional oropharyngeal carriage surveys were conducted among undergraduates at a Rhode Island university. Isolates were characterized using slide agglutination, real-time polymerase chain reaction (rt-PCR), and whole genome sequencing. Adjusted prevalence ratios and 95% confidence intervals were calculated using Poisson regression to determine risk factors for carriage. RESULTS A total of 1837 oropharyngeal specimens were obtained from 1478 unique participants. Overall carriage prevalence was 12.7-14.6% during the two survey rounds, with 1.8-2.6% for capsular genotype B, 0.9-1.0% for capsular genotypes C, W, or Y, and 9.9-10.8% for nongroupable strains by rt-PCR. Meningococcal carriage was associated with being male, smoking, party or club attendance, recent antibiotic use (inverse correlation), and recent respiratory infections. CONCLUSIONS In this university setting, the majority of meningococcal carriage was due to nongroupable strains, followed by serogroup B. Further evaluation is needed to understand the dynamics of serogroup B carriage and disease among university students.
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Affiliation(s)
- Lucy Breakwell
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States; Epidemic Intelligence Service, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30329, United States
| | - Melissa Whaley
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States
| | - Unab I Khan
- University Health Services, Brown University, 13 Brown Street, Providence, RI 02906, United States
| | - Utpala Bandy
- Rhode Island Department of Health, 3 Capitol Hill, Providence, RI 02908, United States
| | | | - Lynn Dupont
- University Health Services, Brown University, 13 Brown Street, Providence, RI 02906, United States
| | - Cindy Vanner
- Rhode Island Department of Health, 3 Capitol Hill, Providence, RI 02908, United States
| | - How-Yi Chang
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States
| | - Jeni T Vuong
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States
| | - Stacey Martin
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States
| | - Jessica R MacNeil
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States
| | - Xin Wang
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States
| | - Sarah A Meyer
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329, United States.
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18
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Thapa S, Gokhale S, Sharma AL, Sapkota LB, Ansari S, Gautam R, Shrestha S, Neopane P. Burden of bacterial upper respiratory tract pathogens in school children of Nepal. BMJ Open Respir Res 2017; 4:e000203. [PMID: 29071076 PMCID: PMC5652512 DOI: 10.1136/bmjresp-2017-000203] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/20/2017] [Accepted: 09/30/2017] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION Respiratory tract infections are one of the most common human infections in all age group and important cause of mortality and morbidity worldwide. Most bacterial upper respiratory tract infections are vaccine preventable. This study aimed to determine the prevalence of carrier state of bacterial upper respiratory tract pathogens among school children. It also aimed to study their antibiograms. METHODS The specimen from posterior pharyngeal wall and tonsils were collected from 204 participants on calcium alginate coated swabs (HiMedia). Isolates were identified by standard microbiological methods and tested for in vitro antibiotic susceptibility testing by modified Kirby-Bauer disc diffusion method. RESULTS In this study, Streptococcus pneumoniae (16.6%) was the most common bacterial pathogen recovered, followed by Staphylococcus aureus (14.7%), β-haemolytic streptococci (non-Group A) (8.8%), Streptococcus pyogenes (5.3%) and Corynebacterium diphtheriae (3.4%). The Gram negative bacteria were Klebsiella pneumoniae (4.9%), Haemophilus influenzae (3.4%) and Neisseria meningitidis (1.4%). Important findings in antibiogram include high resistance of Streptococcus pneumoniae to penicillin (91.17%) and resistance of S. aureus to oxacillin (23.3%). CONCLUSION Pharyngeal colonisation by S. pneumoniae was found high among school children and this calls for an urgent need to include pneumococcal vaccine in routine national immunisation schedule of Nepal given the high burden of invasive pneumococcal disease. Despite expected universal vaccination, pharyngeal colonisation by C. diphtheriae is possible and there is possibility of transmission of these respiratory pathogens to other healthy children.
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Affiliation(s)
- Sangita Thapa
- Department of Clinical Microbiology and Immunology, Chitwan Medical College, Bharatpur, Chitwan, Nepal
| | - Shishir Gokhale
- Department of Clinical Microbiology and Immunology, Manipal College of Medical Sciences, Pokhara, Nepal
| | | | | | - Shamshul Ansari
- Department of Clinical Microbiology and Immunology, Chitwan Medical College, Bharatpur, Chitwan, Nepal
| | - Rajendra Gautam
- Department of Clinical Microbiology and Immunology, Chitwan Medical College, Bharatpur, Chitwan, Nepal
| | - Sony Shrestha
- Department of Clinical Microbiology and Immunology, Chitwan Medical College, Bharatpur, Chitwan, Nepal
| | - Puja Neopane
- Department of Clinical Microbiology and Immunology, Chitwan Medical College, Bharatpur, Chitwan, Nepal
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19
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Allen RC, Engelstädter J, Bonhoeffer S, McDonald BA, Hall AR. Reversing resistance: different routes and common themes across pathogens. Proc Biol Sci 2017; 284:20171619. [PMID: 28954914 PMCID: PMC5627214 DOI: 10.1098/rspb.2017.1619] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 08/23/2017] [Indexed: 11/12/2022] Open
Abstract
Resistance spreads rapidly in pathogen or pest populations exposed to biocides, such as fungicides and antibiotics, and in many cases new biocides are in short supply. How can resistance be reversed in order to prolong the effectiveness of available treatments? Some key parameters affecting reversion of resistance are well known, such as the fitness cost of resistance. However, the population biological processes that actually cause resistance to persist or decline remain poorly characterized, and consequently our ability to manage reversion of resistance is limited. Where do susceptible genotypes that replace resistant lineages come from? What is the epidemiological scale of reversion? What information do we need to predict the mechanisms or likelihood of reversion? Here, we define some of the population biological processes that can drive reversion, using examples from a wide range of taxa and biocides. These processes differ primarily in the origin of revertant genotypes, but also in their sensitivity to factors such as coselection and compensatory evolution that can alter the rate of reversion, and the likelihood that resistance will re-emerge upon re-exposure to biocides. We therefore argue that discriminating among different types of reversion allows for better prediction of where resistance is most likely to persist.
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Affiliation(s)
- Richard C Allen
- Institute of Integrative Biology, ETH Zürich, CH-8092 Zurich, Switzerland
| | - Jan Engelstädter
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia
| | | | - Bruce A McDonald
- Institute of Integrative Biology, ETH Zürich, CH-8092 Zurich, Switzerland
| | - Alex R Hall
- Institute of Integrative Biology, ETH Zürich, CH-8092 Zurich, Switzerland
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20
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Pneumococcal Capsular Polysaccharide Immunity in the Elderly. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00004-17. [PMID: 28424198 DOI: 10.1128/cvi.00004-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Immunity to pneumococcal infections is impaired in older people, and current vaccines are poorly protective against pneumococcal disease in this population. Naturally acquired immunity to pneumococcal capsular polysaccharides develops during childhood and is robust in young adults but deteriorates with advanced age. In particular, antibody levels and function are reduced in older people. Pneumococcal vaccines are recommended for people >65 years old. However, the benefits of polysaccharide and protein-conjugated vaccines in this population are small, because of both serotype replacement and incomplete protection against vaccine serotype pneumococcal disease. In this review, we overview the immune mechanisms by which naturally acquired and vaccine-induced pneumococcal capsular polysaccharide immunity declines with age, including altered colonization dynamics, reduced opsonic activity of antibodies (particularly IgM), and impaired mucosal immunity.
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21
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Kobayashi M, Conklin LM, Bigogo G, Jagero G, Hampton L, Fleming-Dutra KE, Junghae M, Carvalho MDG, Pimenta F, Beall B, Taylor T, Laserson KF, Vulule J, Van Beneden C, Kim L, Feikin DR, Whitney CG, Breiman RF. Pneumococcal carriage and antibiotic susceptibility patterns from two cross-sectional colonization surveys among children aged <5 years prior to the introduction of 10-valent pneumococcal conjugate vaccine - Kenya, 2009-2010. BMC Infect Dis 2017; 17:25. [PMID: 28056828 PMCID: PMC5217209 DOI: 10.1186/s12879-016-2103-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Accepted: 12/08/2016] [Indexed: 12/12/2022] Open
Abstract
Background Pneumococci are spread by persons with nasopharyngeal colonization, a necessary precursor to invasive disease. Pneumococcal conjugate vaccines can prevent colonization with vaccine serotype strains. In 2011, Kenya became one of the first African countries to introduce the 10-valent pneumococcal conjugate vaccine (PCV10) into its national immunization program. Serial cross-sectional colonization surveys were conducted to assess baseline pneumococcal colonization, antibiotic resistance patterns, and factors associated with resistance. Methods Annual surveys were conducted in one urban and one rural site during 2009 and 2010 among children aged <5 years. To reflect differences in vaccine target population, recruitment was age-stratified in Kibera, whereas a simple random sample of children was drawn in Lwak. Nasopharyngeal swabs were collected from eligible children. Pneumococci were isolated and serotyped. Antibiotic susceptibility testing was performed using the 2009 isolates. Antibiotic nonsusceptibility was defined as intermediate susceptibility or resistance to ≥1 antibiotics (i.e., penicillin, chloramphenicol, levofloxacin, erythromycin, tetracycline, cotrimoxazole, and clindamycin); multidrug resistance (MDR) was defined as nonsusceptibility to ≥3 antibiotics. Weighted analysis was conducted when appropriate. Modified Poisson regression was used to calculate factors associated with antibiotic nonsusceptibility. Results Of 1,087 enrolled (Kibera: 740, Lwak: 347), 90.0% of these were colonized with pneumococci, and 37.3% were colonized with PCV10 serotypes. There were no differences by survey site or year. Of 657 (of 730; 90%) isolates tested for antibiotic susceptibility, nonsusceptibility to cotrimoxazole and penicillin was found in 98.6 and 81.9% of isolates, respectively. MDR was found in 15.9% of isolates and most often involved nonsusceptibility to cotrimoxazole and penicillin; 40.4% of MDR isolates were PCV10 serotypes. In the multivariable model, PCV10 serotypes were independently associated with penicillin nonsusceptibility (Prevalence Ratio: 1.2, 95% CI 1.1–1.3), but not with MDR. Conclusions Before PCV10 introduction, nearly all Kenyan children aged <5 years were colonized with pneumococci, and PCV10 serotype colonization was common. PCV10 serotypes were associated with penicillin nonsusceptibility. Given that colonization with PCV10 serotypes is associated with greater risk for invasive disease than colonization with other serotypes, successful PCV10 introduction in Kenya is likely to have a substantial impact in reducing vaccine-type pneumococcal disease and drug-resistant pneumococcal infection. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-2103-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Miwako Kobayashi
- Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA, USA. .,Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA.
| | - Laura M Conklin
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Godfrey Bigogo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.,International Emerging Infections Program, Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Geofrey Jagero
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.,International Emerging Infections Program, Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Lee Hampton
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Katherine E Fleming-Dutra
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Muthoni Junghae
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.,International Emerging Infections Program, Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Maria da Gloria Carvalho
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Fabiana Pimenta
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Bernard Beall
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Thomas Taylor
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Kayla F Laserson
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.,Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - John Vulule
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Chris Van Beneden
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Lindsay Kim
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Daniel R Feikin
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.,International Emerging Infections Program, Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Cynthia G Whitney
- Division of Bacterial Diseases, Centers for Diseases Control and Prevention, 1600 Clifton Road NE, MS C-25, Atlanta, GA, 30329-4027, USA
| | - Robert F Breiman
- International Emerging Infections Program, Centers for Disease Control and Prevention, Nairobi, Kenya.,Emory Global Health Institute, Emory University, Atlanta, GA, USA
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22
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Park C, Kwon EY, Choi SM, Cho SY, Byun JH, Park JY, Lee DG, Kang JH, Shin J, Kim H. Comparative evaluation of a newly developed 13-valent pneumococcal conjugate vaccine in a mouse model. Hum Vaccin Immunother 2016; 13:1169-1176. [PMID: 27960627 PMCID: PMC5443391 DOI: 10.1080/21645515.2016.1261772] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Animal models facilitate evaluation of vaccine efficacy at relatively low cost. This study was a comparative evaluation of the immunogenicity and protective efficacy of a new 13-valent pneumococcal conjugate vaccine (PCV13) with a control vaccine in a mouse model. After vaccination, anti-capsular antibody levels were evaluated by pneumococcal polysaccharide (PnP) enzyme-linked immunosorbent assay (ELISA) and opsonophagocytic killing assay (OPA). Also, mice were challenged intraperitoneally with 100-fold of the 50% lethal dose of Streptococcus pneumoniae. The anti-capsular IgG levels against serotypes 1, 4, 7F, 14, 18C, 19A, and 19F were high (quartile 2 >1,600), while those against the other serotypes were low (Q2 ≤ 800). Also, the OPA titres were similar to those determined by PnP ELISA. Comparative analysis between new PCV13 and control vaccination group in a mouse model exhibited significant differences in serological immunity of a few serotypes and the range of anti-capsular IgG in the population. Challenge of wild-type or neutropenic mice with serotypes 3, 5, 6A, 6B, and 9V showed protective immunity despite of induced relatively low levels of anti-capsular antibodies. With comparison analysis, a mouse model should be adequate for evaluating serological efficacy and difference in the population level as preclinical trial.
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Affiliation(s)
- Chulmin Park
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Eun-Young Kwon
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Su-Mi Choi
- b Division of Infectious Diseases , Department of Internal Medicine, College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Sung-Yeon Cho
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea.,b Division of Infectious Diseases , Department of Internal Medicine, College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Ji-Hyun Byun
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Jung Yeon Park
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Dong-Gun Lee
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea.,b Division of Infectious Diseases , Department of Internal Medicine, College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Jin Han Kang
- a Vaccine Bio Research Institute , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea.,c Department of Pediatrics , College of Medicine, The Catholic University of Korea , Seoul , the Republic of Korea
| | - Jinhwan Shin
- d School of Pharmacy , Sungkyunkwan University , Suwon , the Republic of Korea.,e SK Chemicals Co. Ltd ., Seongnam , Gynuggi-do , the Republic of Korea
| | - Hun Kim
- e SK Chemicals Co. Ltd ., Seongnam , Gynuggi-do , the Republic of Korea
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Kim CJ, Song JS, Choi SJ, Song KH, Choe PG, Park WB, Bang JH, Kim ES, Park SW, Kim HB, Kim NJ, Kim EC, Oh MD. Serotype Distribution and Antimicrobial Susceptibilities of Invasive Streptococcus pneumoniae Isolates from Adults in Korea from 1997 to 2012. J Korean Med Sci 2016; 31:715-23. [PMID: 27134492 PMCID: PMC4835596 DOI: 10.3346/jkms.2016.31.5.715] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 02/17/2016] [Indexed: 11/20/2022] Open
Abstract
In Republic of Korea, a 7-valent pneumococcal conjugated vaccine (PCV7) was licensed for use in infants in 2003, and 13-valent PCV (PCV13) replaced it since 2010. We investigated trends in serotype distribution and antibiotic susceptibility of pneumococcal isolates from adult patients with invasive pneumococcal diseases (IPD). Invasive pneumococcal isolates from adult patients of ≥ 16 years of age were collected from 1997 to 2012. Serotypes of the isolates were determined by the Quellung reaction. Distribution of serotypes was analyzed according to the vaccine types. Antibiotic susceptibility was tested by using E-test strips. A total of 272 invasive pneumococcal isolates were included. The most common serotypes were serotype 19F (8.5%, 23/272), and serotype 3 (8.1%, 22/272), and 24.6% (67/272) of the isolates were of non-vaccine serotypes. Of the 272 isolates, 2.6% (7/272) were penicillin MICs of ≥ 4 µg/mL. The proportion of the PCV13 serotypes decreased from 63.3% (50/79) in 1997-2003 to 48.6% (17/35) in 2011-2012, whereas that of non-vaccine serotypes was 26.6% (21/79) and 25.7% (9/35), respectively, for the same periods. The proportion of the PCV13 serotypes showed a decreasing trend among adult patients with IPD over the study period.
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Affiliation(s)
- Chung Jong Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Jin-Su Song
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Su-Jin Choi
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Kyoung Ho Song
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Pyeong Gyun Choe
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Wan Beom Park
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Ji Hwan Bang
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Eu Suk Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Sang Won Park
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Hong Bin Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Nam-Joong Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Eui-Chong Kim
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Myoung-don Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
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Pneumococcal Colonization Rates in Patients Admitted to a United Kingdom Hospital with Lower Respiratory Tract Infection: a Prospective Case-Control Study. J Clin Microbiol 2016; 54:944-9. [PMID: 26791364 PMCID: PMC4809940 DOI: 10.1128/jcm.02008-15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 12/29/2015] [Indexed: 11/20/2022] Open
Abstract
Current diagnostic tests are ineffective for identifying the etiological pathogen in hospitalized adults with lower respiratory tract infections (LRTIs). The association of pneumococcal colonization with disease has been suggested as a means to increase the diagnostic precision. We compared the pneumococcal colonization rates and the densities of nasal pneumococcal colonization by (i) classical culture and (ii) quantitative real-time PCR (qPCR) targetinglytAin patients with LRTIs admitted to a hospital in the United Kingdom and control patients. A total of 826 patients were screened for inclusion in this prospective case-control study. Of these, 38 patients were recruited, 19 with confirmed LRTIs and 19 controls with other diagnoses. Nasal wash (NW) samples were collected at the time of recruitment. Pneumococcal colonization was detected in 1 patient with LRTI and 3 controls (P= 0.6) by classical culture. By qPCR, pneumococcal colonization was detected in 10 LRTI patients and 8 controls (P= 0.5). Antibiotic usage prior to sampling was significantly higher in the LRTI group than in the control group (19 versus 3;P< 0.001). With a clinically relevant cutoff of >8,000 copies/ml on qPCR, pneumococcal colonization was found in 3 LRTI patients and 4 controls (P> 0.05). We conclude that neither the prevalence nor the density of nasal pneumococcal colonization (by culture and qPCR) can be used as a method of microbiological diagnosis in hospitalized adults with LRTI in the United Kingdom. A community-based study recruiting patients prior to antibiotic therapy may be a useful future step.
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Sanchez JL, Cooper MJ, Myers CA, Cummings JF, Vest KG, Russell KL, Sanchez JL, Hiser MJ, Gaydos CA. Respiratory Infections in the U.S. Military: Recent Experience and Control. Clin Microbiol Rev 2015; 28:743-800. [PMID: 26085551 PMCID: PMC4475643 DOI: 10.1128/cmr.00039-14] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
This comprehensive review outlines the impact of military-relevant respiratory infections, with special attention to recruit training environments, influenza pandemics in 1918 to 1919 and 2009 to 2010, and peacetime operations and conflicts in the past 25 years. Outbreaks and epidemiologic investigations of viral and bacterial infections among high-risk groups are presented, including (i) experience by recruits at training centers, (ii) impact on advanced trainees in special settings, (iii) morbidity sustained by shipboard personnel at sea, and (iv) experience of deployed personnel. Utilizing a pathogen-by-pathogen approach, we examine (i) epidemiology, (ii) impact in terms of morbidity and operational readiness, (iii) clinical presentation and outbreak potential, (iv) diagnostic modalities, (v) treatment approaches, and (vi) vaccine and other control measures. We also outline military-specific initiatives in (i) surveillance, (ii) vaccine development and policy, (iii) novel influenza and coronavirus diagnostic test development and surveillance methods, (iv) influenza virus transmission and severity prediction modeling efforts, and (v) evaluation and implementation of nonvaccine, nonpharmacologic interventions.
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Affiliation(s)
- Jose L Sanchez
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Michael J Cooper
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | | | - James F Cummings
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Kelly G Vest
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Kevin L Russell
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Joyce L Sanchez
- Mayo Clinic, Division of General Internal Medicine, Rochester, Minnesota, USA
| | - Michelle J Hiser
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA Oak Ridge Institute for Science and Education, Postgraduate Research Participation Program, U.S. Army Public Health Command, Aberdeen Proving Ground, Aberdeen, Maryland, USA
| | - Charlotte A Gaydos
- International STD, Respiratory, and Biothreat Research Laboratory, Division of Infectious Diseases, Johns Hopkins University, Baltimore, Maryland, USA
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Sensing of interleukin-1 cytokines during Streptococcus pneumoniae colonization contributes to macrophage recruitment and bacterial clearance. Infect Immun 2015; 83:3204-12. [PMID: 26034210 DOI: 10.1128/iai.00224-15] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 05/22/2015] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae (the pneumococcus), a leading cause of bacterial disease, is most commonly carried in the human nasopharynx. Colonization induces inflammation that promotes the organism's growth and transmission. This inflammatory response is dependent on intracellular sensing of bacterial components that access the cytosolic compartment via the pneumococcal pore-forming toxin pneumolysin. In vitro, cytosolic access results in cell death that includes release of the proinflammatory cytokine interleukin-1β (IL-1β). IL-1 family cytokines, including IL-1β, are secreted upon activation of inflammasomes, although the role of this activation in the host immune response to pneumococcal carriage is unknown. Using a murine model of pneumococcal nasopharyngeal colonization, we show that mice deficient in the interleukin-1 receptor type 1 (Il1r1(-/-)) have reduced numbers of neutrophils early after infection, fewer macrophages later in carriage, and prolonged bacterial colonization. Moreover, intranasal administration of Il-1β promoted clearance. Macrophages are the effectors of clearance, and characterization of macrophage chemokines in colonized mice revealed that Il1r1(-/-) mice have lower expression of the C-C motif chemokine ligand 6 (CCL6), correlating with reduced macrophage recruitment to the nasopharynx. IL-1 family cytokines are known to promote adaptive immunity; however, we observed no difference in the development of humoral or cellular immunity to pneumococcal colonization between wild-type and Il1r1(-/-) mice. Our findings show that sensing of IL-1 cytokines during colonization promotes inflammation without immunity, which may ultimately benefit the pneumococcus.
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Méndez-Lage S, Losada-Castillo I, Agulla-Budiño A. [Streptococcus pneumoniae: serotype distribution, antimicrobial susceptibility, risk factors and mortality in Galicia over a two year-period]. Enferm Infecc Microbiol Clin 2015; 33:579-84. [PMID: 25726037 DOI: 10.1016/j.eimc.2015.01.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 01/13/2015] [Accepted: 01/15/2015] [Indexed: 11/25/2022]
Abstract
INTRODUCTION To examine the epidemiology of pneumococcal infection in Galicia (Spain) after the incorporation of the pneumococcal conjugate vaccine, and to determine serotype distribution, antibiotic susceptibility, risk factors and associated mortality in cases of invasive pneumococcal disease (IPD) during 2011 and 2012. METHODS All strains causing IPD in Galicia were studied. Serotyping was performed by agglutination and Quellung reaction. Antibiotic sensitivity to penicillin, cefotaxime, erythromycin, vancomycin, and levofloxacin was determined. The risk factors considered were chronic respiratory disease, heart disease, liver disease, kidney disease, diabetes mellitus, and HIV and non-HIV immunodeficiency. RESULTS A total of 555 strains were collected, with 43 different serotypes being found. The most frequently isolated ones were: serotype3 (17.5%), serotype7F (12.6%), serotype19A (9.4%), serotype14 (4.1%), serotype6C (4.1%), serotype11A (4%) and serotype22F (3.8%). 57.1% of isolates were serotypes included in VNC-13V. Two non-penicillin-sensitive strains and two others were not sensitive to cefotaxime, and 24.7% of the strains were not susceptible to erythromycin (26.9% in 2011 and 22.5% in 2012). The case fatality rate was 16.5%, reaching 23.3% in patients over 75years. Diseases with a statistically significant risk of mortality were: liver, kidney and immunodeficiency without HIV. CONCLUSIONS Serotype3 was the most frequent in Galicia. Very few strains were not susceptible to penicillin. Erythromycin resistance decreased from 2011 to 2012. It is highlighted that mortality increases with age. Liver disease, renal disease and non-HIV immunodeficiency increases the mortality risk.
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Affiliation(s)
- Susana Méndez-Lage
- Servicio de Microbiología, Complexo Hospitalario de Ferrol, Ferrol, A Coruña, España
| | - Isabel Losada-Castillo
- Servicio de Epidemioloxía, Dirección Xeral de Innovación e Xestión da Saúde Pública, Santiago de Compostela, A Coruña, España
| | - Andrés Agulla-Budiño
- Servicio de Microbiología, Complexo Hospitalario de Ferrol, Ferrol, A Coruña, España.
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Mameli C, Fabiano V, Daprai L, Bedogni G, Faccini M, Garlaschi ML, Penagini F, Dilillo D, Torresani E, Gramegna M, Zuccotti GV. A longitudinal study of streptococcus pneumoniae carriage in healthy children in the 13-valent pneumococcal conjugate vaccine era. Hum Vaccin Immunother 2015; 11:811-7. [PMID: 25751237 PMCID: PMC4514434 DOI: 10.1080/21645515.2015.1010945] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 12/29/2014] [Accepted: 01/11/2015] [Indexed: 01/27/2023] Open
Abstract
Few epidemiological data are available after the introduction of the 13-valent pneumococcal vaccine (PCV13) in 2010. We performed repeat nasopharyngeal swabs and evaluated the serotype distribution of Streptococcus pneumoniae (SP) and its association with PCV13 vaccine status in healthy Italian children aged 3-59 months. SP serotypes were assessed by the Quellung reaction. 618 children appropriately (28%) or incompletely (72%) vaccinated for age with PCV13 were available at baseline (T0). 515 were re-evaluated at 6 months from baseline (T6) and 436 at 12 months from baseline (T12). The percentage of appropriately vaccinated subjects at T0, T6 and T12 was 28%, 67% and 92%, respectively. Random effects logistic regression models with robust 95% confidence intervals was used to estimate the time-related changes in SP and PCV13 carriage and marginal probabilities were obtained from such models. The age-corrected probability of SP carriage was 0.31 (95% CI 0.22 - 0.41) at T0, 0.32 (0.24 - 0.40) at T6 and 0.28 (0.20 - 0.35) at T12. The probability of PCV13 serotypes carriage was 0.025 (0.001 - 0.050) at T0, 0.018 (0.001 - 0.039) at T6 and 0.010 (0.001 - 0.023) at T12. A decrease in PCV13 serotypes and a shift in non-PCV13 serotypes colonization was observed. In particular, the 15A serotype accounted for 4%, 8% and 23% of SP isolates at T0, T6 and T12, respectively. In conclusion, the benefits of the PCV13 vaccination on SP carriage increase with increasing coverage rates. The shift of SP isolates toward non-PCV13 serotypes needs to be studied further.
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Affiliation(s)
- Chiara Mameli
- Department of Pediatrics; Children's Hospital “V. Buzzi"; University of Milan; Milan, Italy
| | - Valentina Fabiano
- Department of Pediatrics; Children's Hospital “V. Buzzi"; University of Milan; Milan, Italy
| | - Laura Daprai
- Microbiology Laboratory; IRCCS Cà Granda Ospedale Maggiore Policlinico Foundation; Milan, Italy
| | - Giorgio Bedogni
- Clinical Epidemiology Unit; Liver Research Center; Basovizza, Trieste, Italy
| | - Marino Faccini
- Prevention Department; Local Health Authority; Milan, Italy
| | - Maria Laura Garlaschi
- Microbiology Laboratory; IRCCS Cà Granda Ospedale Maggiore Policlinico Foundation; Milan, Italy
| | - Francesca Penagini
- Department of Pediatrics; Children's Hospital “V. Buzzi"; University of Milan; Milan, Italy
| | - Dario Dilillo
- Department of Pediatrics; Children's Hospital “V. Buzzi"; University of Milan; Milan, Italy
| | - Erminio Torresani
- Microbiology Laboratory; IRCCS Cà Granda Ospedale Maggiore Policlinico Foundation; Milan, Italy
| | - Maria Gramegna
- Unità Organizzativa Governo della Prevenzione e Tutela sanitaria; Direzione Generale Sanità; Milan, Italy
| | - Gian Vincenzo Zuccotti
- Department of Pediatrics; Children's Hospital “V. Buzzi"; University of Milan; Milan, Italy
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30
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Read RC, Baxter D, Chadwick DR, Faust SN, Finn A, Gordon SB, Heath PT, Lewis DJM, Pollard AJ, Turner DPJ, Bazaz R, Ganguli A, Havelock T, Neal KR, Okike IO, Morales-Aza B, Patel K, Snape MD, Williams J, Gilchrist S, Gray SJ, Maiden MCJ, Toneatto D, Wang H, McCarthy M, Dull PM, Borrow R. Effect of a quadrivalent meningococcal ACWY glycoconjugate or a serogroup B meningococcal vaccine on meningococcal carriage: an observer-blind, phase 3 randomised clinical trial. Lancet 2014; 384:2123-31. [PMID: 25145775 DOI: 10.1016/s0140-6736(14)60842-4] [Citation(s) in RCA: 216] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND Meningococcal conjugate vaccines protect individuals directly, but can also confer herd protection by interrupting carriage transmission. We assessed the effects of meningococcal quadrivalent glycoconjugate (MenACWY-CRM) or serogroup B (4CMenB) vaccination on meningococcal carriage rates in 18-24-year-olds. METHODS In this phase 3, observer-blind, randomised controlled trial, university students aged 18-24 years from ten sites in England were randomly assigned (1:1:1, block size of three) to receive two doses 1 month apart of Japanese Encephalitis vaccine (controls), 4CMenB, or one dose of MenACWY-CRM then placebo. Participants were randomised with a validated computer-generated random allocation list. Participants and outcome-assessors were masked to the treatment group. Meningococci were isolated from oropharyngeal swabs collected before vaccination and at five scheduled intervals over 1 year. Primary outcomes were cross-sectional carriage 1 month after each vaccine course. Secondary outcomes included comparisons of carriage at any timepoint after primary analysis until study termination. Reactogenicity and adverse events were monitored throughout the study. Analysis was done on the modified intention-to-treat population, which included all enrolled participants who received a study vaccination and provided at least one assessable swab after baseline. This trial is registered with ClinicalTrials.gov, registration number NCT01214850. FINDINGS Between Sept 21 and Dec 21, 2010, 2954 participants were randomly assigned (987 assigned to control [984 analysed], 979 assigned to 4CMenB [974 analysed], 988 assigned to MenACWY-CRM [983 analysed]); 33% of the 4CMenB group, 34% of the MenACWY-CRM group, and 31% of the control group were positive for meningococcal carriage at study entry. By 1 month, there was no significant difference in carriage between controls and 4CMenB (odds ratio 1·2, 95% CI 0·8-1·7) or MenACWY-CRM (0·9, [0·6-1·3]) groups. From 3 months after dose two, 4CMenB vaccination resulted in significantly lower carriage of any meningococcal strain (18·2% [95% CI 3·4-30·8] carriage reduction), capsular groups BCWY (26·6% [10·5-39·9] carriage reduction), capsular groups CWY (29·6% [8·1-46·0] carriage reduction), and serogroups CWY (28·5% [2·8-47·5] carriage reduction) compared with control vaccination. Significantly lower carriage rates were also noted in the MenACWY-CRM group compared with controls: 39·0% (95% CI 17·3-55·0) carriage reduction for serogroup Y and 36·2% (15·6-51·7) carriage reduction for serogroup CWY. Study vaccines were generally well tolerated, with increased rates of transient local injection pain and myalgia in the 4CMenB group. No safety concerns were identified. INTERPRETATION Although we detected no significant difference between groups at 1 month after vaccine course, MenACWY-CRM and 4CMenB vaccines reduced meningococcal carriage rates during 12 months after vaccination and therefore might affect transmission when widely implemented. FUNDING Novartis Vaccines.
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Affiliation(s)
- Robert C Read
- Academic Unit of Clinical Experimental Sciences and NIHR Southampton Respiratory Biomedical Research Unit, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
| | - David Baxter
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | | | - Saul N Faust
- Academic Unit of Clinical Experimental Sciences and NIHR Southampton Respiratory Biomedical Research Unit, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK; Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Adam Finn
- Schools of Clinical Science and Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Stephen B Gordon
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Paul T Heath
- Division of Clinical Sciences, St George's, University of London, London, UK
| | - David J M Lewis
- Surrey Clinical Research Centre, University of Surrey, Guildford, UK
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Centre, Oxford, UK
| | - David P J Turner
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Rohit Bazaz
- Department of Infection and Immunity, University of Sheffield, Sheffield, UK
| | - Amitava Ganguli
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Tom Havelock
- Academic Unit of Clinical Experimental Sciences and NIHR Southampton Respiratory Biomedical Research Unit, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK; Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Keith R Neal
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | | | - Begonia Morales-Aza
- Schools of Clinical Science and Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Kamlesh Patel
- NIHR Wellcome Trust Clinical Research Facility, Manchester Royal Infirmary, Manchester, UK
| | - Matthew D Snape
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Centre, Oxford, UK
| | - John Williams
- The James Cook University Hospital, Middlesborough, UK
| | | | - Steve J Gray
- Public Health England, Manchester Royal Infirmary, Manchester, UK
| | | | | | - Huajun Wang
- Novartis Vaccines and Diagnostics, Cambridge, MA, USA
| | | | - Peter M Dull
- Novartis Vaccines and Diagnostics, Cambridge, MA, USA
| | - Ray Borrow
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Public Health England, Manchester Royal Infirmary, Manchester, UK
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Hausdorff WP, Hoet B, Adegbola RA. Predicting the impact of new pneumococcal conjugate vaccines: serotype composition is not enough. Expert Rev Vaccines 2014; 14:413-28. [PMID: 25266168 DOI: 10.1586/14760584.2015.965160] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Streptococcus pneumoniae is a major cause of childhood morbidity and mortality worldwide. A heptavalent polysaccharide-protein conjugate vaccine (PCV) has proven highly effective in preventing pneumococcal disease in industrialized countries. Two higher-valent pneumococcal conjugate vaccines are now widely available, even in the poorest countries. These differ from each other in the number of serotypes and carrier proteins used for their conjugation. Some have assumed that the only meaningful clinical difference between PCV formulations is a function of the number of serotypes each contains. A careful review of recent clinical data with these and several unlicensed PCV formulations points to important similarities but also that some key properties of each vaccine likely differ from one another.
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A bivalent vaccine based on a replication-incompetent influenza virus protects against Streptococcus pneumoniae and influenza virus infection. J Virol 2014; 88:13410-7. [PMID: 25210171 DOI: 10.1128/jvi.01205-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
UNLABELLED Streptococcus pneumoniae is a major causative pathogen in community-acquired pneumonia; together with influenza virus, it represents an important public health burden. Although vaccination is the most effective prophylaxis against these infectious agents, no single vaccine simultaneously provides protective immunity against both S. pneumoniae and influenza virus. Previously, we demonstrated that several replication-incompetent influenza viruses efficiently elicit IgG in serum and IgA in the upper and lower respiratory tracts. Here, we generated a replication-incompetent hemagglutinin knockout (HA-KO) influenza virus possessing the sequence for the antigenic region of pneumococcal surface protein A (PspA). Although this virus (HA-KO/PspA virus) could replicate only in an HA-expressing cell line, it infected wild-type cells and expressed both viral proteins and PspA. PspA- and influenza virus-specific antibodies were detected in nasal wash and bronchoalveolar lavage fluids and in sera from mice intranasally inoculated with HA-KO/PspA virus, and mice inoculated with HA-KO/PspA virus were completely protected from lethal challenge with either S. pneumoniae or influenza virus. Further, bacterial colonization of the nasopharynx was prevented in mice immunized with HA-KO/PspA virus. These results indicate that HA-KO/PspA virus is a promising bivalent vaccine candidate that simultaneously confers protective immunity against both S. pneumoniae and influenza virus. We believe that this strategy offers a platform for the development of bivalent vaccines, based on replication-incompetent influenza virus, against pathogens that cause respiratory infectious diseases. IMPORTANCE Streptococcus pneumoniae and influenza viruses cause contagious diseases, but no single vaccine can simultaneously provide protective immunity against both pathogens. Here, we used reverse genetics to generate a replication-incompetent influenza virus carrying the sequence for the antigenic region of pneumococcal surface protein A and demonstrated that mice immunized with this virus were completely protected from lethal doses of infection with either influenza virus or Streptococcus pneumoniae. We believe that this strategy, which is based on a replication-incompetent influenza virus possessing the antigenic region of other respiratory pathogens, offers a platform for the development of bivalent vaccines.
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Oishi K, Tamura K, Akeda Y. Global control of pneumococcal infections by pneumococcal vaccines. Trop Med Health 2014; 42:83-6. [PMID: 25425955 PMCID: PMC4204060 DOI: 10.2149/tmh.2014-s11] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Streptococcus pneumoniae is a major worldwide cause of morbidity and mortality. Pneumococcal carriage is considered to be an important source of horizontal spread of this pathogen within the community. Pneumococcal conjugate vaccine (PCV) is capable of inducing serotype-specific antibodies in sera of infants, and has been suggested to reduce nasopharyngeal carriage of vaccine-type pneumococci in children. PCV is generally immunogenic for pediatric patients with invasive pneumococcal disease, with an exception for the infecting serotypes. Based on evidences from the clinical trials of PCV, the health impact of childhood pneumococcal pneumonia appears to be high in developing countries where most of global childhood pneumonia deaths occur. PCV vaccination may prevent hundreds of deaths per 100,000 children vaccinated in developing countries, while PCV vaccination is expected to prevent less than 10 deaths per 100,000 children vaccinated in the developed countries. Therefore, the WHO has proposed a strategy to reduce the incidence of severe pneumonia by 75% in child less than 5 years of age compared to 2010 levels by 2025.
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Affiliation(s)
- Kazunori Oishi
- Infectious Disease Surveillance Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjyuku, Tokyo162-8640, Japan
| | - Kazuyo Tamura
- Laboratory for Clinical Research on Infectious Disease, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka
| | - Yukihiro Akeda
- Laboratory for Clinical Research on Infectious Disease, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka
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Rivera-Olivero IA, del Nogal B, Fuentes M, Cortez R, Bogaert D, Hermans PW, Waard JHD. Immunogenicity of a 7-valent pneumococcal conjugate vaccine (PCV7) and impact on carriage in Venezuelan children at risk of invasive pneumococcal diseases. Vaccine 2014; 32:4006-11. [DOI: 10.1016/j.vaccine.2014.04.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 03/06/2014] [Accepted: 04/14/2014] [Indexed: 10/25/2022]
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De Cao E, Melegaro A, Klok R, Postma M. Optimising assessments of the epidemiological impact in The Netherlands of paediatric immunisation with 13-valent pneumococcal conjugate vaccine using dynamic transmission modelling. PLoS One 2014; 9:e89415. [PMID: 24694656 PMCID: PMC3973563 DOI: 10.1371/journal.pone.0089415] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/21/2014] [Indexed: 11/26/2022] Open
Abstract
This work is the first attempt to quantify the overall effects of a 13-valent pneumococcal conjugate vaccine (PCV13) vaccination programme in the Dutch population taking into account all the direct and indirect effects of the vaccine on invasive pneumococcal disease. Using available Dutch data, a dynamic transmission model for the spread of pneumococci and potential subsequent invasive pneumococcal disease has been adapted to the Dutch setting. Overall, invasive pneumococcal disease cases in the Netherlands are predicted to decrease from a pre-vaccination level of 2623 cases annually to 2475, 2289, 2185, 2179, and 2178 cases annually 5-, 10-, 20-, 30-, and 40-years, respectively, post-vaccination. Therefore, vaccination with PCV13 in the Netherlands is predicted to lower invasive pneumococcal disease cases per year by up to 445 cases in the medium- to long-term. The results are quite robust for the sensitivity analyses performed on the parameters that regulate herd immunity and competition between vaccine and non-vaccine types.
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Affiliation(s)
- Elisabetta De Cao
- Department of Pharmacy, University of Groningen, Groningen, Netherlands
- Department of Economics, Econometrics and Finance, University of Groningen, Groningen, Netherlands
| | - Alessia Melegaro
- Policy Analysis and Public Management Department and Dondena Centre for Research on Social Dynamics, Bocconi University, Milan, Italy
| | - Rogier Klok
- Pfizer bv, Specialty Care Business Unit, Capelle a/d IJssel, Netherlands
| | - Maarten Postma
- Department of Pharmacy, University of Groningen, Groningen, Netherlands
- * E-mail:
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A Poly-N-acetylglucosamine-Shiga toxin broad-spectrum conjugate vaccine for Shiga toxin-producing Escherichia coli. mBio 2014; 5:e00974-14. [PMID: 24667709 PMCID: PMC3977355 DOI: 10.1128/mbio.00974-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Many pathogens produce the β-(1-6)-linked poly-N-acetylglucosamine (PNAG) surface polysaccharide that is being developed as a broadly protective antimicrobial vaccine. However, it is unknown whether systemically injected PNAG vaccines or antibodies would provide protective immunity against pathogens confined to the gastrointestinal tract such as Shiga toxin (Stx)-producing Escherichia coli (STEC), an important group of gastrointestinal (GI) pathogens for which effective immunotherapeutics are lacking. To ascertain whether systemic IgG antibody to PNAG impacts this infectious situation, a vaccine consisting of a synthetic nonamer of nonacetylated PNAG, 9GlcNH2, conjugated to the Shiga toxin 1b subunit (9GlcNH2-Stx1b) was produced. Rabbit antibodies raised to the conjugate vaccine were tested for bacterial killing and toxin neutralization in vitro and protection against infection in infant mice. Cell surface PNAG was detected on all 9 STEC isolates tested, representing 6 STEC serogroups, including E. coli O157:H7. Antibody to the 9GlcNH2-Stx1b conjugate neutralized Stx1 potently and Stx2 modestly. For O157:H7 and O104:H4 STEC strains, antibodies elicited by the 9GlcNH2-Stx1b conjugate possessed opsonic killing and bactericidal activity. Following intraperitoneal injection, antibodies to both PNAG and Stx were needed for infant mouse protection against O157 STEC. These antibodies also mediated protection against the Stx2-producing O104:H4 strain that was the cause of a recent outbreak in Germany, although sufficient doses of antibody to PNAG alone were protective against this strain in infant mice. Our observations suggest that vaccination against both PNAG and Stx, using a construct such as the 9GlcNH2-Stx1b conjugate vaccine, would be protective against a broad range of STEC serogroups. IMPORTANCE The presence of poly-N-acetylglucosamine (PNAG) on many pathogens presents an opportunity to target this one structure with a multispecies vaccine. Whether antibodies to PNAG can protect against pathogens confined to the gastrointestinal tract is not known. As Shiga toxin (Stx)-producing Escherichia coli (STEC) bacteria are serious causes of infection whose virulence is dependent on elaboration of Stx, we prepared a vaccine containing a synthetic nonamer of PNAG (9GlcNH2) conjugated to Shiga toxin 1b subunit (9GlcNH2-Stx1b) to evaluate bacterial killing, toxin neutralization, and protective efficacy in infant mice. All nine (100%) clinical strains of STEC from different serogroups expressed PNAG. Vaccine-induced antibody mediated in vitro killing of STEC and neutralization of both Stx1 and Stx2. Passive administration of antibody to the conjugate showed protection requiring immunity to both PNAG and Stx for O157 strains, although for an O104 strain, antibody to PNAG alone was protective. Immunity to PNAG may contribute to protection against STEC infections.
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Secular trends in invasive meningococcal disease, Massachusetts, 1988–2011: what happened to invasive disease? Epidemiol Infect 2014; 142:2483-90. [DOI: 10.1017/s0950268814000259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
SUMMARYInvasive meningococcal disease (IMD) reported to the Massachusetts Department of Public Health from 1988 to 2011 was reviewed. The average annual incidence of IMD/100 000 decreased from 1·57 [95% confidence interval (CI) 1·42–1·73] for 1988–1991 to 0·22 (95% CI 0·17–0·29) for 2008–2011. The pattern of decreasing incidence over time differed by age group. There was a decrease in IMD/100 000 in the 0–4 years age group after 1991 from 10·92 (95% CI 8·08–14·70) in 1991 to 5·76 (95% CI 3·78–8·72) in 1992. Incidence in the 0–4 years age group remained below 5/100 000 per year on average thereafter. A substantial reduction in incidence in all age groups was observed between 2000 and 2009, which began before the introduction of conjugate meningococcal vaccine in 2005. Marked reductions in incidence of IMD in Massachusetts, and elsewhere, deserve further investigation with respect to potential factors that go beyond the introduction and deployment of improved meningococcal vaccines.
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Poolman JT, Peeters CCAM, van den Dobbelsteen GPJM. The history of pneumococcal conjugate vaccine development: dose selection. Expert Rev Vaccines 2014; 12:1379-94. [DOI: 10.1586/14760584.2013.852475] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
Otitis media is a major cause of morbidity in 80% of all children less than 3 years of age and often goes undiagnosed in the general population. There is evidence to suggest that the incidence of otitis media is increasing. The major cause of otitis media is infection of the middle ear with microbes from the nasopharynx. The anatomical orientation of the eustachian tube, in association with a number of risk factors, predisposes infants and young children to the infection. Bacteria are responsible for approximately 70% of cases of acute otitis media, with Streptococcus pneumoniae, nontypeable Haemophilus influenzae and Moraxella catarrhalis predominating as the causative agents. The respiratory viruses, respiratory syncytial virus, rhinovirus, parainfluenza and influenza, account for 30% of acute otitis media cases. Over the past decade, there has been a profound increase in the reported resistance to antibiotics, which, with increased disease burden, has focussed attention on vaccine development for otitis media. A polymicrobial formulation containing antigens from all major pathogens would have the greatest potential to deliver a sustained reduction in the disease burden globally. The disappointing outcomes for otitis media seen with the polysaccharide pneumococcal conjugate vaccine have raised major challenges for the vaccination strategy. Clearly, more knowledge is required concerning immune mechanisms in the middle ear, as well as vaccine formulations containing antigens that are more representative of the polymicrobial nature of the disease. Antigens that have been extensively tested in animal models are now available for testing in human subjects.
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Affiliation(s)
- Allan W Cripps
- Griffith University, School of Medicine, Gold Coast Campus, PMB 50, Gold Coast, MC, QLD, 9726, Australia.
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Flasche S, Edmunds WJ, Miller E, Goldblatt D, Robertson C, Choi YH. The impact of specific and non-specific immunity on the ecology of Streptococcus pneumoniae and the implications for vaccination. Proc Biol Sci 2013; 280:20131939. [PMID: 24089337 PMCID: PMC3790488 DOI: 10.1098/rspb.2013.1939] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/11/2013] [Indexed: 01/24/2023] Open
Abstract
More than 90 capsular serotypes of Streptococcus pneumoniae coexist despite competing for nasopharyngeal carriage and a gradient in fitness. The underlying mechanisms for this are poorly understood and make assessment of the likely population impact of vaccination challenging. We use an individual-based simulation model to generalize widely used deterministic models for pneumococcal competition and show that in these models short-term serotype-specific and serotype non-specific immunity could constitute the mechanism governing between-host competition and coexistence. We find that non-specific immunity induces between-host competition and that serotype-specific immunity limits a type's competitive advantage and allows stable coexistence of multiple serotypes. Serotypes carried at low prevalence show high variance in carriage levels, which would result in apparent outbreaks if they were highly pathogenic. Vaccination against few serotypes can lead to elimination of the vaccine types and induces replacement by others. However, in simulations where the elimination of the targeted types is achieved only by a combination of vaccine effects and the competitive pressure of the non-vaccine types, a universal vaccine with similar-type-specific effectiveness can fail to eliminate pneumococcal carriage and offers limited herd immunity. Hence, if vaccine effects are insufficient to control the majority of serotypes at the same time, then exploiting the competitive pressure by selective vaccination can help control the most pathogenic serotypes.
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Affiliation(s)
- Stefan Flasche
- Immunisation, Hepatitis and Blood Safety Department, Public Health England, 61 Colindale Avenue, Colindale, London NW9 5EQ, UK
- Department of Mathematics and Statistics, Strathclyde University, 26 Richmond Street, Glasgow G1 1XH, UK
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - W. John Edmunds
- Immunisation, Hepatitis and Blood Safety Department, Public Health England, 61 Colindale Avenue, Colindale, London NW9 5EQ, UK
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Elizabeth Miller
- Immunisation, Hepatitis and Blood Safety Department, Public Health England, 61 Colindale Avenue, Colindale, London NW9 5EQ, UK
| | - David Goldblatt
- Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Chris Robertson
- Department of Mathematics and Statistics, Strathclyde University, 26 Richmond Street, Glasgow G1 1XH, UK
- Health Protection Scotland, 5 Cadogan Street, Glasgow G2 6QE, UK
- International Prevention Research Institute, 95 Cours Lafayette, Lyon 69006, France
| | - Yoon Hong Choi
- Immunisation, Hepatitis and Blood Safety Department, Public Health England, 61 Colindale Avenue, Colindale, London NW9 5EQ, UK
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Hackel M, Lascols C, Bouchillon S, Hilton B, Morgenstern D, Purdy J. Serotype prevalence and antibiotic resistance in Streptococcus pneumoniae clinical isolates among global populations. Vaccine 2013; 31:4881-7. [DOI: 10.1016/j.vaccine.2013.07.054] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 01/18/2013] [Accepted: 07/18/2013] [Indexed: 11/26/2022]
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Pichichero ME. Protein carriers of conjugate vaccines: characteristics, development, and clinical trials. Hum Vaccin Immunother 2013; 9:2505-23. [PMID: 23955057 DOI: 10.4161/hv.26109] [Citation(s) in RCA: 161] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The immunogenicity of polysaccharides as human vaccines was enhanced by coupling to protein carriers. Conjugation transformed the T cell-independent polysaccharide vaccines of the past to T cell-dependent antigenic vaccines that were much more immunogenic and launched a renaissance in vaccinology. This review discusses the conjugate vaccines for prevention of infections caused by Hemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis. Specifically, the characteristics of the proteins used in the construction of the vaccines including CRM, tetanus toxoid, diphtheria toxoid, Neisseria meningitidis outer membrane complex, and Hemophilus influenzae protein D are discussed. The studies that established differences among and key features of conjugate vaccines including immunologic memory induction, reduction of nasopharyngeal colonization and herd immunity, and antibody avidity and avidity maturation are presented. Studies of dose, schedule, response to boosters, of single protein carriers with single and multiple polysaccharides, of multiple protein carriers with multiple polysaccharides and conjugate vaccines administered concurrently with other vaccines are discussed along with undesirable consequences of conjugate vaccines. The clear benefits of conjugate vaccines in improving the protective responses of the immature immune systems of young infants and the senescent immune systems of the elderly have been made clear and opened the way to development of additional vaccines using this technology for future vaccine products.
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Weil Olivier C. Ten years of experience with the pneumococcal conjugate 7-valent vaccine in children. Med Mal Infect 2013; 43:309-21. [DOI: 10.1016/j.medmal.2013.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Revised: 03/11/2013] [Accepted: 04/25/2013] [Indexed: 11/30/2022]
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Choe YJ, Choi EH, Lee HJ. The changing epidemiology of childhood pneumococcal disease in Korea. Infect Chemother 2013; 45:145-58. [PMID: 24265963 PMCID: PMC3780948 DOI: 10.3947/ic.2013.45.2.145] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Indexed: 11/30/2022] Open
Abstract
The wide use of antimicrobial agents and 7-valent pneumococcal conjugate vaccine (PCV7) has led to major changes in the epidemiology of childhood pneumococcal diseases. In Korea, data on the population-based incidence of childhood invasive pneumococcal diseases (IPD) are not available; however, institution-based surveillance data suggest a substantial burden of childhood IPD. Following the introduction of the PCV7 in Korea in 2003, the proportion of IPD caused by vaccine-type pneumococci has decreased, while non-PCV7 serotypes, especially serotypes 19A and 6A, whose proportions had been increasing before the introduction of the vaccine, became predominant among childhood IPD isolates. This article reviews the overall impact of PCV7 utilization and summarizes the results obtained so far. Continuous monitoring and gathering of scientific evidence for the epidemiological transition of pneumococcal carriage and IPD will be important for the management of pneumococcal infections in Korea.
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Affiliation(s)
- Young June Choe
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul, Korea
| | - Eun Hwa Choi
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul, Korea
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
| | - Hoan Jong Lee
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul, Korea
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
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Abstract
Healthy infants and toddlers who attend day care centers are at increased risk for contracting common childhood illnesses such as viral upper and lower respiratory illnesses, viral gastrointestinal infections, and acute and chronic otitis media. The author proposes that this high frequency of common infections be termed daycaritis. Daycaritis imposes significant social and economic burdens on both the family and the health care system. This review describes the most common infections seen in day care attendees, preventative measures to decrease the rates of illness, and a practical approach to diagnosis and management in the emergency department.
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Affiliation(s)
- Pamela Bailey
- Section of Emergency Medicine, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
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Rudolph K, Bruce M, Bruden D, Zulz T, Wenger J, Reasonover A, Harker-Jones M, Hurlburt D, Hennessy T. Epidemiology of pneumococcal serotype 6A and 6C among invasive and carriage isolates from Alaska, 1986-2009. Diagn Microbiol Infect Dis 2012; 75:271-6. [PMID: 23276772 DOI: 10.1016/j.diagmicrobio.2012.11.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 10/19/2012] [Accepted: 11/21/2012] [Indexed: 11/19/2022]
Abstract
We investigated serotype 6A/6C invasive pneumococcal disease (IPD) incidence, genetic diversity, and carriage before and after 7-valent pneumococcal conjugate vaccine (PCV7) introduction in Alaska. IPD cases (1986-2009) were identified through population-based laboratory surveillance. Isolates were initially serotyped by conventional methods, and 6C isolates were differentiated from 6A by polymerase chain reaction. Among invasive and carriage isolates initially typed as 6A, 35% and 50% were identified as 6C, respectively. IPD rates caused by serotype 6A or 6C among children <5 years did not change from the pre- to post-PCV7 period (P = 0.71 and P = 0.09, respectively). Multilocus sequence typing of IPD isolates revealed 28 sequence types. The proportion of serotype 6A carriage isolates decreased from 7.4% pre-PCV7 to 1.8% (P < 0.001) during 2008-2009; the proportion of serotype 6C carriage isolates increased from 3.0% to 8.4% (P = 0.004) among children <5 years. Continued surveillance is warranted to monitor changes in serotype distribution and prevalence.
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Affiliation(s)
- Karen Rudolph
- Arctic Investigations Program, Centers for Disease Control and Prevention, Anchorage, AK 99508, USA
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Simell B, Auranen K, Käyhty H, Goldblatt D, Dagan R, O'Brien KL. The fundamental link between pneumococcal carriage and disease. Expert Rev Vaccines 2012; 11:841-55. [PMID: 22913260 DOI: 10.1586/erv.12.53] [Citation(s) in RCA: 445] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Streptococcus pneumoniae (pneumococcus) is a major cause of worldwide mortality and morbidity, and to a large extent is vaccine-preventable. Nasopharyngeal carriage of pneumococcus precedes disease and is the source of pneumococcal spread between people. The use of vaccine effect on carriage as part of the vaccine licensure and post-vaccine introduction evaluation could facilitate and expand the licensure of new, life-saving pneumococcal vaccines and enable a comprehensive estimate of population effects after vaccine introduction. The authors provide a review of the evidence supporting pneumococcal carriage at the individual level as an immediate and necessary precursor to pneumococcal disease. Based on such a causal link between carriage and disease, the authors emphasize the role of information on pneumococcal carriage in vaccine trials and in public health decision-making.
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Affiliation(s)
- Birgit Simell
- Department of Vaccination and Immune Protection, National Institute for Health and Welfare, Helsinki, Finland
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Weil-Olivier C, van der Linden M, de Schutter I, Dagan R, Mantovani L. Prevention of pneumococcal diseases in the post-seven valent vaccine era: a European perspective. BMC Infect Dis 2012; 12:207. [PMID: 22954038 PMCID: PMC3462147 DOI: 10.1186/1471-2334-12-207] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 08/31/2012] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND The burden of invasive pneumococcal disease in young children decreased dramatically following introduction of the 7-valent pneumococcal conjugate vaccine (PCV7). The epidemiology of S. pneumoniae now reflects infections caused by serotypes not included in PCV7. Recently introduced higher valency pneumococcal vaccines target the residual burden of invasive and non-invasive infections, including those caused by serotypes not included in PCV7. This review is based on presentations made at the European Society of Pediatric Infectious Diseases in June 2011. DISCUSSION Surveillance data show increased circulation of the non-PCV7 vaccine serotypes 1, 3, 6A, 6C, 7 F and 19A in countries with routine vaccination. Preliminary evidence suggests that broadened serotype coverage offered by higher valency vaccines may be having an effect on invasive disease caused by some of those serotypes, including 19A, 7 F and 6C. Aetiology of community acquired pneumonia remains a difficult clinical diagnosis. However, recent reports indicate that pneumococcal vaccination has reduced hospitalisations of children for vaccine serotype pneumonia. Variations in serotype circulation and occurrence of complicated and non-complicated pneumonia caused by non-PCV7 serotypes highlight the potential of higher valency vaccines to decrease the remaining burden. PCVs reduce nasopharyngeal carriage and acute otitis media (AOM) caused by vaccine serotypes. Recent investigations of the interaction between S. pneumoniae and non-typeable H. influenzae suggest that considerable reduction in severe, complicated AOM infections may be achieved by prevention of early pneumococcal carriage and AOM infections. Extension of the vaccine serotype spectrum beyond PCV7 may provide additional benefit in preventing the evolution of AOM. The direct and indirect costs associated with pneumococcal disease are high, thus herd protection and infections caused by non-vaccine serotypes both have strong effects on the cost effectiveness of pneumococcal vaccination. Recent evaluations highlight the public health significance of indirect benefits, prevention of pneumonia and AOM and coverage of non-PCV7 serotypes by higher valency vaccines. SUMMARY Routine vaccination has greatly reduced the burden of pneumococcal diseases in children. The pneumococcal serotypes present in the 7-valent vaccine have greatly diminished among disease isolates. The prevalence of some non-vaccine serotypes (e.g. 1, 7 F and 19A) has increased. Pneumococcal vaccines with broadened serotype coverage are likely to continue decreasing the burden of invasive disease, and community acquired pneumonia in children. Further reductions in pneumococcal carriage and increased prevention of early AOM infections may prevent the evolution of severe, complicated AOM. Evaluation of the public health benefits of pneumococcal conjugate vaccines should include consideration of non-invasive pneumococcal infections, indirect effects of vaccination and broadened serotype coverage.
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Affiliation(s)
| | - Mark van der Linden
- Department of Medical Microbiology, National Reference Center for Streptococci, University Hospital RWTH Aachen, Aachen, Germany
| | - Iris de Schutter
- Department. of Pediatric Pneumology, Cystic Fibrosis Clinic and Pediatric Infectious Diseases, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Ron Dagan
- Pediatric Infectious Disease Unit, Soroka University Medical Center and Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, Israel
| | - Lorenzo Mantovani
- CIRFF/Center of Pharmacoeconomics, Faculty of Pharmacy, University of Naples, Naples, Italy
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Ota MOC, Roca A, Bottomley C, Hill PC, Egere U, Greenwood B, Adegbola RA. Pneumococcal antibody concentrations of subjects in communities fully or partially vaccinated with a seven-valent pneumococcal conjugate vaccine. PLoS One 2012; 7:e42997. [PMID: 22916192 PMCID: PMC3419246 DOI: 10.1371/journal.pone.0042997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 07/16/2012] [Indexed: 11/19/2022] Open
Abstract
Background A recent trial with PCV-7 in a rural Gambian community showed reduced vaccine-type pneumococcal carriage in fully vaccinated compared with control communities. We measured pneumococcal polysaccharide antibody concentrations in this trial to understand further the mechanisms underlying the observed changes. Methods A single-blind, cluster-randomized (by village) trial was conducted in 21 Gambian villages. In 11 villages, all residents received PCV-7 (Vaccine group); in 10 control villages only children <30 months old or those born during the study received PCV-7. Subjects over the age of 30 months resident in vaccine villages received a single dose of PCV-7 whilst those in control villages received a single dose of a serogroup C meningococcal conjugate vaccine. Serum antibody concentrations against specific pneumococcal polysaccharides were measured in approximately 200 age-stratified subjects before, 4–6, 12 and 24 months following vaccination. Results Baseline pneumococcal antibody concentrations were generally high and increased with age up to 10 years. One dose of PCV-7 increased geometric mean antibody concentrations (GMC) in vaccinated versus control villages for vaccine serotypes 6B and 18C, and 4 and 18C, in the young (under 5 years) and older age groups (5+ years) respectively. There were significantly higher proportions of subjects in the vaccinated than in the control communities with an antibody concentration believed to protect against carriage (>5.0 µg/mL) for all but serotype 9V of the PCV-7 serotypes in the older group, but not in the younger age group. Conclusion Higher antibodies in vaccinated communities provide an explanation for the lower pneumococcal carriage rates in fully vaccinated compared to control communities. Trial Registration Controlled-Trials.com ISRCTN51695599 51695599.
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Thoon KC, Chong CY, Tee NWS. Early impact of pneumococcal conjugate vaccine on invasive pneumococcal disease in Singapore children, 2005 through 2010. Int J Infect Dis 2012; 16:e209-15. [DOI: 10.1016/j.ijid.2011.11.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 07/01/2011] [Accepted: 11/30/2011] [Indexed: 12/01/2022] Open
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