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Bai D, Kim H, Wang P. Development of semisynthetic saponin immunostimulants. Med Chem Res 2024; 33:1292-1306. [PMID: 39132259 PMCID: PMC11315725 DOI: 10.1007/s00044-024-03227-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2024] [Accepted: 04/20/2024] [Indexed: 08/13/2024]
Abstract
Many natural saponins demonstrate immunostimulatory adjuvant activities, but they also have some inherent drawbacks that limit their clinical use. To overcome these limitations, extensive structure-activity-relationship (SAR) studies have been conducted. The SAR studies of QS-21 and related saponins reveal that their respective fatty side chains are crucial for potentiating a strong cellular immune response. Replacing the hydrolytically unstable ester side chain in the C28 oligosaccharide domain with an amide side chain in the same domain or in the C3 branched trisaccharide domain is a viable approach for generating robust semisynthetic saponin immunostimulants. Given the striking resemblance of natural momordica saponins (MS) I and II to the deacylated Quillaja Saponaria (QS) saponins (e.g., QS-17, QS-18, and QS-21), incorporating an amide side chain into the more sustainable MS, instead of deacylated QS saponins, led to the discovery of MS-derived semisynthetic immunostimulatory adjuvants VSA-1 and VSA-2. This review focuses on the authors' previous work on SAR studies of QS and MS saponins.
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Affiliation(s)
- Di Bai
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL AL35294 USA
| | - Hyunjung Kim
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL AL35294 USA
| | - Pengfei Wang
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL AL35294 USA
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2
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Kaur R, Gonzalez E, Pham M, Pichichero M. Naturally-induced serum antibody levels in children to pneumococcal polysaccharide 15B that correlate with protection from nasopharyngeal colonization but anti-serotype 15B antibody has low functional cross-reactivity with serotype 15C. Vaccine 2023; 41:7265-7273. [PMID: 37925318 DOI: 10.1016/j.vaccine.2023.10.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/19/2023] [Accepted: 10/20/2023] [Indexed: 11/06/2023]
Abstract
BACKGROUND Serotypes 15B and 15C have been added to new different pneumococcal-conjugate vaccines (PCV20 and V116, respectively). We determined a serum anti-15B antibody level that would be a correlate of protection (COP) against nasopharyngeal colonization and assessed functional cross-reactivity against serotype 15B and 15C in children following natural immunization. METHOD IgG-antibody to serotype 15B polysaccharide was measured by ELISA in 341 sera from 6 to 36 month old children collected before, at the time of, and after pneumococcal colonization caused by serotypes 15B and 15C. 155 age-matched controls who had no detected colonization caused by serotype 15B or 15C strains were used as controls. A two-step method was used for construction of COP models: a generalized estimating equation followed by logistic-regression. Opsonophagocytic (OPA) assays assessed functional cross-reactivity between serotypes 15B and 15C. RESULTS The derived COP for prevention of colonization was 1.18 µg/ml for serotype 15B and 0.63 µg/ml for serotype 15C, with a predictive probability of 80 %. Antibody levels did not correlate with OPA titers. 30 % of child samples, with moderate to high amounts of ELISA-measured antibody, showed no OPA titer against either serotype 15B or 15C. For remaining samples, very low or no functional cross-reactivity between serotypes 15B and 15C was measured. CONCLUSIONS A COP for prevention of colonization in young children based on naturally-induced antibody levels was derived for serotypes 15B and 15C that differed. Antibody levels correlated poorly with OPA titers and low functional cross-reactivity between serotypes 15B and 15C in child sera was observed.
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Affiliation(s)
- Ravinder Kaur
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester, NY, United States.
| | - Eduardo Gonzalez
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester, NY, United States
| | - Minh Pham
- San Francisco State University, 1600 Holloway Ave, San Francisco, CA, United States
| | - Michael Pichichero
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester, NY, United States
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Wong A, Kramer SC, Piccininni M, Rohmann JL, Kurth T, Escolano S, Grittner U, Domenech de Cellès M. Using LASSO Regression to Estimate the Population-Level Impact of Pneumococcal Conjugate Vaccines. Am J Epidemiol 2023; 192:1166-1180. [PMID: 36935107 PMCID: PMC10326487 DOI: 10.1093/aje/kwad061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 12/12/2022] [Accepted: 03/13/2023] [Indexed: 03/21/2023] Open
Abstract
Pneumococcal conjugate vaccines (PCVs) protect against diseases caused by Streptococcus pneumoniae, such as meningitis, bacteremia, and pneumonia. It is challenging to estimate their population-level impact due to the lack of a perfect control population and the subtleness of signals when the endpoint-such as all-cause pneumonia-is nonspecific. Here we present a new approach for estimating the impact of PCVs: using least absolute shrinkage and selection operator (LASSO) regression to select variables in a synthetic control model to predict the counterfactual outcome for vaccine impact inference. We first used a simulation study based on hospitalization data from Mexico (2000-2013) to test the performance of LASSO and established methods, including the synthetic control model with Bayesian variable selection (SC). We found that LASSO achieved accurate and precise estimation, even in complex simulation scenarios where the association between the outcome and all control variables was noncausal. We then applied LASSO to real-world hospitalization data from Chile (2001-2012), Ecuador (2001-2012), Mexico (2000-2013), and the United States (1996-2005), and found that it yielded estimates of vaccine impact similar to SC. The LASSO method is accurate and easily implementable and can be applied to study the impact of PCVs and other vaccines.
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Affiliation(s)
- Anabelle Wong
- Correspondence to Anabelle Wong, Infectious Disease Epidemiology Research Group, Max Planck Institute for Infection Biology, Charitéplatz 1, 10117 Berlin, Germany (e-mail: )
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Kim H, Yu J, Bai D, Nahm MH, Wang P. Potentiating pneumococcal glycoconjugate vaccine PCV13 with saponin adjuvant VSA-1. Front Immunol 2022; 13:1079047. [PMID: 36578488 PMCID: PMC9790987 DOI: 10.3389/fimmu.2022.1079047] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 11/21/2022] [Indexed: 12/14/2022] Open
Abstract
VSA-1 is a semisynthetic saponin adjuvant prepared from naturally occurring Momordica saponin and capable of stimulating antigen-specific humoral and cellular immune responses. Its immunostimulating activity in enhancing the immune responses induced by the clinical glycoconjugate pneumococcal vaccine PCV13 is compared with QS-21 in female BALB/c mice. Both VSA-1 and QS-21 boosted IgG and opsonic antibodies titers against seven selected serotypes, including serotypes 3, 14, and 19A that are involved in most PCV13 breakthroughs. Since VSA-1 is much more accessible and of lower toxicity than QS-21, it can be a practical saponin immunostimulant to be included in a new glycoconjugate pneumococcal vaccine formulation.
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Affiliation(s)
- Hyunjung Kim
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jigui Yu
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Di Bai
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Moon H. Nahm
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States,World Health Organization (WHO) Pneumococcal Serology Reference Laboratory, University of Alabama at Birmingham, Birmingham, AL, United States,*Correspondence: Moon H. Nahm, ; Pengfei Wang,
| | - Pengfei Wang
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, United States,*Correspondence: Moon H. Nahm, ; Pengfei Wang,
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Mokaddas E, Syed S, Albert MJ. The 13-valent pneumococcal conjugate vaccine (PCV13) does not appear to provide much protection on combined invasive disease due to the six PCV13 non-PCV7 serotypes 1, 3, 5, 6A, 7F, and 19A in Kuwait during 2010-2019. Hum Vaccin Immunother 2021; 17:4661-4666. [PMID: 34435932 DOI: 10.1080/21645515.2021.1968216] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Kuwait started immunizing children <2 y age with the 7-valent pneumococcal conjugate vaccine, PCV7 from August 2007. PCV7 was replaced by the 13-valent conjugate vaccine, PCV13 from August 2010. In a previous analysis of the results for the period, August 2010-July 2013 (period II), there was no evidence of serotype-specific protection for invasive disease against the additional six serotypes to PCV7 present in PCV13 (non-PCV7 serotypes) as evidenced by isolation from blood and cerebrospinal fluid in any of the age groups, <2 y, 2-5 y, 6-50 y, 51-65 y, and >65 y and all ages, compared to the pre-vaccination period, August 2003-July 2006 (period I). In the current study, we allowed additional time, August 2013-July 2019 (period III) for better vaccine effect and repeated the analysis. We did not find any significant decrease of invasive disease due to the non-PCV7 serotypes of PCV13 in period III and combined II and III periods compared to period I. However, these comparisons showed significant reductions for four of the six and total serotypes of PCV7, and total serotypes of PCV13. Reduction for total PCV13 serotypes was contributed by serotypes of PCV7. It appears that the six non-PCV7 serotypes in PCV13 do not offer much protection. Some contributory factors for the poor effect of the non-PCV7 serotypes may be related to few cases with underpowered statistical analysis, lack of vaccine coverage data, method of vaccine efficacy analysis based on vaccine serotypes relative to all serotypes and unusual rise in non-typeable isolates post vaccination that would have masked true serotypes.
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Affiliation(s)
- Eiman Mokaddas
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Shabeera Syed
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - M John Albert
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
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Nahm MH, Brissac T, Kilian M, Vlach J, Orihuela CJ, Saad JS, Ganaie F. Pneumococci Can Become Virulent by Acquiring a New Capsule From Oral Streptococci. J Infect Dis 2020; 222:372-380. [PMID: 31605125 PMCID: PMC7457184 DOI: 10.1093/infdis/jiz456] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 09/05/2019] [Indexed: 12/20/2022] Open
Abstract
Pneumococcal conjugate vaccines have been successful, but their use has increased infections by nonvaccine serotypes. Oral streptococci often harbor capsular polysaccharide (PS) synthesis loci (cps). Although this has not been observed in nature, if pneumococcus can replace its cps with oral streptococcal cps, it may increase its serotype repertoire. In the current study, we showed that oral Streptococcus strain SK95 and pneumococcal strain D39 both produce structurally identical capsular PS, and their genetic backgrounds influence the amount of capsule production and shielding from nonspecific killing. SK95 is avirulent in a well-established in vivo mouse model. When acapsular pneumococcus was transformed with SK95 cps, the transformant became virulent and killed all mice. Thus, cps from oral Streptococcus strains can make acapsular pneumococcus virulent, and interspecies cps transfer should be considered a potential mechanism of serotype replacement. Our findings, along with publications from the US Centers for Disease Control and Prevention, highlight potential limitations of the 2013 World Health Organization criterion for studying pneumococcal serotypes carried without isolating bacteria. We show that an oral streptococcal strain, SK95, and a pneumococcal strain, D39, both produce chemically identical capsular PS. We also show that transferring SK95 cps into noncapsulated, avirulent pneumococcus gave it the capacity for virulence in a mouse model.
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Affiliation(s)
- Moon H Nahm
- Department of Medicine, University of Alabama at Birmingham, Birmingham, USA
| | - Terry Brissac
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Mogens Kilian
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Jiri Vlach
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Carlos J Orihuela
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jamil S Saad
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Feroze Ganaie
- Department of Medicine, University of Alabama at Birmingham, Birmingham, USA
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López-Sanguos C, Rivero Calle I, Rodriguez Tenreiro C, Raguindin PF, Martinón-Torres F. Safety and immunogenicity of pneumococcal conjugate vaccines in preterm infants. Expert Opin Drug Saf 2019; 18:253-259. [PMID: 30907170 DOI: 10.1080/14740338.2019.1597849] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
INTRODUCTION The introduction of pneumococcal conjugate vaccines (PCVs) in the routine immunization program has resulted in a significant decline in invasive pneumococcal diseases (IPD) around the world. Preterm infants are a special group at a high risk of invasive infection by encapsulated bacteria. However, their slow growth accrual and prolonged hospital stay frequently lead to delays in immunization, which contributes to their risk for severe infections. Areas covered: Authors reviewed the published immunogenicity and safety of the use of PCVs in preterm infants. Expert opinion: PCVs are safe and effective for use in low birth weight and in-hospital preterm infants. Local and systemic reactions are similar for both term and preterm populations. Reports were inconsistent on the risk of apnea, therefore hospitalized extremely premature infants should be kept under observation for at least 48 h after immunization.
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Affiliation(s)
- Carolina López-Sanguos
- a Translational Paediatrics and Infectious Diseases, Department of Paediatrics , Hospital Clínico Universitario de Santiago de Compostela , Santiago de Compostela , Spain.,b Genetics, Vaccines and Infections Research Group (GENVIP) , Instituto de Investigación Sanitaria de Santiago , Santiago de Compostela , Spain
| | - Irene Rivero Calle
- a Translational Paediatrics and Infectious Diseases, Department of Paediatrics , Hospital Clínico Universitario de Santiago de Compostela , Santiago de Compostela , Spain.,b Genetics, Vaccines and Infections Research Group (GENVIP) , Instituto de Investigación Sanitaria de Santiago , Santiago de Compostela , Spain
| | - Carmen Rodriguez Tenreiro
- a Translational Paediatrics and Infectious Diseases, Department of Paediatrics , Hospital Clínico Universitario de Santiago de Compostela , Santiago de Compostela , Spain.,b Genetics, Vaccines and Infections Research Group (GENVIP) , Instituto de Investigación Sanitaria de Santiago , Santiago de Compostela , Spain
| | - Peter Francis Raguindin
- b Genetics, Vaccines and Infections Research Group (GENVIP) , Instituto de Investigación Sanitaria de Santiago , Santiago de Compostela , Spain
| | - Federico Martinón-Torres
- a Translational Paediatrics and Infectious Diseases, Department of Paediatrics , Hospital Clínico Universitario de Santiago de Compostela , Santiago de Compostela , Spain.,b Genetics, Vaccines and Infections Research Group (GENVIP) , Instituto de Investigación Sanitaria de Santiago , Santiago de Compostela , Spain
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González-Miró M, Radecker AM, Rodríguez-Noda LM, Fariñas-Medina M, Zayas-Vignier C, Hernández-Cedeño M, Serrano Y, Cardoso F, Santana-Mederos D, García-Rivera D, Valdés-Balbín Y, Vérez-Bencomo V, Rehm BHA. Design and Biological Assembly of Polyester Beads Displaying Pneumococcal Antigens as Particulate Vaccine. ACS Biomater Sci Eng 2018; 4:3413-3424. [DOI: 10.1021/acsbiomaterials.8b00579] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Majela González-Miró
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
- Institute of Fundamental Sciences, Massey University, Colombo Road, Palmerston North 4422, New Zealand
| | - Anna-Maria Radecker
- Institute of Fundamental Sciences, Massey University, Colombo Road, Palmerston North 4422, New Zealand
| | - Laura M. Rodríguez-Noda
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Mildrey Fariñas-Medina
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Caridad Zayas-Vignier
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Mabel Hernández-Cedeño
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Yohana Serrano
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Félix Cardoso
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Darielys Santana-Mederos
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Dagmar García-Rivera
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Yury Valdés-Balbín
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Vicente Vérez-Bencomo
- Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba
| | - Bernd H. A. Rehm
- Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Don Young Road, Nathan Campus, Nathan, Queensland 4111, Australia
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Brooks LRK, Mias GI. Streptococcus pneumoniae's Virulence and Host Immunity: Aging, Diagnostics, and Prevention. Front Immunol 2018; 9:1366. [PMID: 29988379 PMCID: PMC6023974 DOI: 10.3389/fimmu.2018.01366] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/01/2018] [Indexed: 12/14/2022] Open
Abstract
Streptococcus pneumoniae is an infectious pathogen responsible for millions of deaths worldwide. Diseases caused by this bacterium are classified as pneumococcal diseases. This pathogen colonizes the nasopharynx of its host asymptomatically, but overtime can migrate to sterile tissues and organs and cause infections. Pneumonia is currently the most common pneumococcal disease. Pneumococcal pneumonia is a global health concern and vastly affects children under the age of five as well as the elderly and individuals with pre-existing health conditions. S. pneumoniae has a large selection of virulence factors that promote adherence, invasion of host tissues, and allows it to escape host immune defenses. A clear understanding of S. pneumoniae's virulence factors, host immune responses, and examining the current techniques available for diagnosis, treatment, and disease prevention will allow for better regulation of the pathogen and its diseases. In terms of disease prevention, other considerations must include the effects of age on responses to vaccines and vaccine efficacy. Ongoing work aims to improve on current vaccination paradigms by including the use of serotype-independent vaccines, such as protein and whole cell vaccines. Extending our knowledge of the biology of, and associated host immune response to S. pneumoniae is paramount for our improvement of pneumococcal disease diagnosis, treatment, and improvement of patient outlook.
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Affiliation(s)
- Lavida R. K. Brooks
- Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
- Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, United States
| | - George I. Mias
- Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, United States
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, United States
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Abstract
BACKGROUND Data on pediatric HIV in Peru are limited. The National Institute of Child Health (Instituto Nacional de Salud del Niño: INSN) cares for the most HIV-infected children under the age of 18 years in the country. We describe the outcomes of children seen at INSN's HIV clinic over the 10 years when antiretroviral therapy and prevention of mother-to-child transmission (PMTCT) interventions became available in 2004. METHODS We conducted a retrospective review of INSN HIV clinic patients between 2003 and 2012. Deidentified data were collected and analyzed. RESULTS A total of 280 children were included: 50.0% (140/280) were male; 80.0% (224/280) lived in metropolitan Lima. Perinatal transmission was the mode of HIV infection in 91.4% (256/280) of children. Only 17% (32/191) of mothers were known to be HIV-infected at delivery; of these mothers, 41% (13/32) were receiving antiretroviral therapy at delivery, 72% (23/32) delivered by Cesarean section and 47% (15/32) of their infants received antiretroviral prophylaxis. Median age at HIV diagnosis for all children was 35.7 months (interquartile range 14.5-76.8 months), and 67% (143/213) had advanced disease (clinical stage C). After HIV diagnosis, the most frequent hospitalization discharge diagnoses were bacterial pneumonia, chronic malnutrition, diarrhea, anemia and tuberculosis. Twenty-four patients (8.6%) died at a median age of 77.4 months. CONCLUSIONS Most cases of pediatric HIV were acquired via perinatal transmission; few mothers were diagnosed before delivery; and among mothers with known HIV status, PMTCT was suboptimal even after national PMTCT policy was implemented. Most children were diagnosed with advanced disease. These findings underscore the need for improving early pediatric HIV diagnosis and treatment, as well as PMTCT strategies.
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Modeling Possible Inclusion of Pneumococcal Conjugate Vaccine into the National Immunization Program for Infants in India. Value Health Reg Issues 2018; 15:99-105. [DOI: 10.1016/j.vhri.2018.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 02/26/2018] [Accepted: 03/03/2018] [Indexed: 11/23/2022]
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The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017. [PMID: 28637806 DOI: 10.1128/cvi.00099-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acetyltransferase gene wciZ The coding sequence of wciZ contains eight consecutive TA repeats [(TA)8]. Replication slippage is thought to result in the addition or loss of TA repeats, subsequently causing frameshift and truncation of WciZ to yield a nonacetylated serotype, 15C. Using sensitive serological tools, we show that serotype 15C isolates whose wciZ contains seven or nine TA repeats retain partial O-acetylation, while serotype 15C isolates whose wciZ contains six TA repeats have barely detectable O-acetylation. We confirmed by inhibition enzyme-linked immunosorbent assay that (TA)7 serotype 15C is ∼0.1% as acetylated as serotype 15B, while serotype 15X is nonacetylated. To eliminate the impact of genetic background, we created isogenic serotype 15B, (TA)7 serotype 15C, and 15BΔwciZ (15X) strains and found that reduction or absence of WciZ-mediated O-acetylation did not affect capsular shielding from phagocytes, biofilm formation, adhesion to nasopharyngeal cells, desiccation tolerance, or murine colonization. Sera from PPV23-immunized persons opsonized serotype 15B significantly but only slightly better than serotypes 15C and 15X; thus, PPV23 may not result in expansion of serotype 15C.
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Navalkele P, Özgönenel B, McGrath E, Lephart P, Sarnaik S. Invasive Pneumococcal Disease in Patients With Sickle Cell Disease. J Pediatr Hematol Oncol 2017; 39:341-344. [PMID: 28538501 DOI: 10.1097/mph.0000000000000858] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Patients with sickle cell disease (SCD) are at risk of fatal sepsis with encapsulated bacteria, such as Streptococcus pneumoniae, because of the inherent autosplenectomy that occurs in SCD. This risk is thwarted with oral penicillin prophylaxis during the first 5 years of life, and with stringent vaccination against S. pneumoniae alongside routine childhood immunization. But compared with the general African American pediatric population, the rate of invasive pneumococcal disease (IPD) in patients with SCD still remains high, resulting in hospitalization and fatality. METHODS Patients with SCD who developed IPD from 2004 up to 2013 were identified using microbiology records. Descriptive analysis of presence of risk factors for IPD, type of SCD, pneumococcal vaccination and prophylaxis status, clinical presentation, microbiological data, and the outcome of IPD was performed. RESULTS Eight patients with SCD developed IPD (7 bacteremia and 1 respiratory tract infection). Three of the 8 isolates underwent serotype analysis (15 C in 2 and 15A in 1), none covered with the current vaccination program. One patient had fatal outcome (15A). CONCLUSIONS Breakthrough cases of IPD may involve nonvaccine isolates, and seem to occur after 5 years of age when oral penicillin prophylaxis has been terminated.
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Affiliation(s)
- Pournima Navalkele
- *The Carman and Ann Adams Department of Pediatrics, Wayne State University, Children's Hospital of Michigan, Detroit †Pediatric Hematology and Oncology §Pediatric Infectious Diseases, Detroit ∥Department of Microbiology, Detroit Medical Center University Laboratories, Detroit, MI ‡Department of Pediatrics, Saint Louis University, Cardinal Glennon Children's Hospital, Saint Louis, MO
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González-Miro M, Rodríguez-Noda L, Fariñas-Medina M, García-Rivera D, Vérez-Bencomo V, Rehm BH. Self-assembled particulate PsaA as vaccine against Streptococcus pneumoniae infection. Heliyon 2017; 3:e00291. [PMID: 28435909 PMCID: PMC5390691 DOI: 10.1016/j.heliyon.2017.e00291] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 03/31/2017] [Indexed: 12/19/2022] Open
Abstract
Streptococcus pneumoniae is a human pathogen responsible for the majority of childhood pneumonia and media otitis cases worldwide. The diversity of its capsular polysaccharides (CPS) results in more than 91 serotypes of which at least 23 are virulent. Various CPS conjugated to immunogenic carrier proteins are currently licensed and provide protection against the infection caused by the respective serotypes but not against new and emerging virulent serotypes. In this study, we considered the conserved protein antigen PsaA, the pneumococcal surface adhesin A, in order to overcome the limitations of CPS antigens. The PsaA was translationally fused to a polyhydroxybutyrate (PHB) synthase which mediated production of PsaA displayed on PHB inclusions in recombinant Escherichia coli. This suggested that the PsaA fusion to the PHB synthase did not interfere with PHB synthase activity and its ability to mediate formation of nano-sized inclusions composed of a PHB core surrounded by the PHB synthase fused to PsaA. Isolated PHB beads showed a negative surface charge. Transmission electron microscopy analysis suggested that the PsaA fusion to the PHB synthase reduced the size of PHB beads from about 500 nm to 100 nm. The integrity and antigenicity of the fusion protein attached to isolated PHB beads was confirmed by SDS-PAGE, tryptic peptide fingerprinting analysis using MALDI-TOF-MS/MS and immunoblotting using a monoclonal anti-PsaA antibody. Mice immunized with PsaA displaying PHB beads produced high and specific IgG levels dominated by IgG1 isotype. While IgG1 titer were similar between soluble and insoluble PsaA, the IgG2 titers were strongly increased upon vaccination with insoluble PsaA i.e. PsaA displayed on PHB beads. Particulate PsaA-PHB beads elicited IgG antibodies recognizing PsaA in whole cell lysates of seven different serotypes of S. pneumoniae. This study suggested that PHB beads are suitable carriers for PsaA in order to induce a significant and specific Th-2-type immune response.
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Affiliation(s)
- Majela González-Miro
- Finlay Institute, La Havana, Cuba
- Institute of Fundamental Sciences and MacDiarmid Institute of Advanced Materials and Nanotechnology, Massey University, Palmerston North, New Zealand
| | | | | | | | | | - Bernd H.A. Rehm
- Institute of Fundamental Sciences and MacDiarmid Institute of Advanced Materials and Nanotechnology, Massey University, Palmerston North, New Zealand
- Australian Institute of Innovative Materials, University of Wollongong, Australia
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Jonnalagadda S, Rodríguez O, Estrella B, Sabin LL, Sempértegui F, Hamer DH. Etiology of severe pneumonia in Ecuadorian children. PLoS One 2017; 12:e0171687. [PMID: 28182741 PMCID: PMC5300242 DOI: 10.1371/journal.pone.0171687] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 01/24/2017] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND In Latin America, community-acquired pneumonia remains a major cause of morbidity and mortality among children. Few studies have examined the etiology of pneumonia in Ecuador. METHODS This observational study was part of a randomized, double blind, placebo-controlled clinical trial conducted among children aged 2-59 months with severe pneumonia in Quito, Ecuador. Nasopharyngeal and blood samples were tested for bacterial and viral etiology by polymerase chain reaction. Risk factors for specific respiratory pathogens were also evaluated. RESULTS Among 406 children tested, 159 (39.2%) had respiratory syncytial virus (RSV), 71 (17.5%) had human metapneumovirus (hMPV), and 62 (15.3%) had adenovirus. Streptococcus pneumoniae was identified in 37 (9.2%) samples and Mycoplasma pneumoniae in three (0.74%) samples. The yearly circulation pattern of RSV (P = 0.0003) overlapped with S. pneumoniae, (P = 0.03) with most cases occurring in the rainy season. In multivariable analysis, risk factors for RSV included younger age (adjusted odds ratio [aOR] = 1.9, P = 0.01) and being underweight (aOR = 1.8, P = 0.04). Maternal education (aOR = 0.82, P = 0.003), pulse oximetry (aOR = 0.93, P = 0.005), and rales (aOR = 0.25, P = 0.007) were associated with influenza A. Younger age (aOR = 3.5, P = 0.007) and elevated baseline respiratory rate were associated with HPIV-3 infection (aOR = 0.94, P = 0.03). CONCLUSION These results indicate the importance of RSV and influenza, and potentially modifiable risk factors including undernutrition and future use of a RSV vaccine, when an effective vaccine becomes available. TRIAL REGISTRATION ClinicalTrials.gov NCT 00513929.
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Affiliation(s)
- Sivani Jonnalagadda
- Center for Global Health and Development, Boston University School of Public Health, Boston, Massachusetts, United States of America
| | | | - Bertha Estrella
- Corporación Ecuatoriana de Biotecnología, Quito, Ecuador
- Universidad Central del Ecuador, Escuela de Medicina, Quito, Ecuador
| | - Lora L. Sabin
- Center for Global Health and Development, Boston University School of Public Health, Boston, Massachusetts, United States of America
- Department of Global Health, Boston University School of Public Health, Boston, Massachusetts, United States of America
| | - Fernando Sempértegui
- Corporación Ecuatoriana de Biotecnología, Quito, Ecuador
- Universidad Central del Ecuador, Escuela de Medicina, Quito, Ecuador
| | - Davidson H. Hamer
- Center for Global Health and Development, Boston University School of Public Health, Boston, Massachusetts, United States of America
- Department of Global Health, Boston University School of Public Health, Boston, Massachusetts, United States of America
- Section of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States of America
- Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, United States of America
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Safety and Immunogenicity of Pneumococcal Conjugate Vaccine in Preterm Infants: A Meta-Analysis. Indian J Pediatr 2017; 84:101-110. [PMID: 27819116 DOI: 10.1007/s12098-016-2248-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Accepted: 10/17/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To assess the safety and immunogenicity of pneumococcal conjugate vaccine (PCVs) in preterm infants. METHODS In accordance with the PRISM (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement (as of May 2015), a meta-analysis was conducted to evaluate the safety and immunogenicity of PCVs in preterm infants. RESULTS Ten thousand nine hundred sixty full-term infants and 2131 preterm infants with 344 preterm infants of <2500 g birth weight [low-birth weight (LBW)] were included, and all the subjects were immunized with either PCV-7, PCV-10 or PCV-13 in this random-effects meta-analysis. For safety, the range of risk ratio (RRs) for local reaction was from 0.88 to 1.02 and from 0.94 to 1.24 for systematic reaction respectively. For immunogenicity, either post-primary or booster vaccination with PCV-7, PCV-10 or PCV-13, genomic mean concentration (GMC) of serotypes 4, 6B, 9 V, 19F and 23F was always less in preterm infants than in full-term infants, in which huge comparison of GMC was found in serotype 19F(SMD = -0.393, 95%CI:-0.612 ~ 0.175). After primary vaccination, the combined risk ratio (RRs) of immune response against seven common serotypes and additional serotype 1 was approximated to 1.00 with narrow 95 % confidence interval (CI) between preterm infants and full-term infants, and at least 91 % sero-conversion of two additional serotypes, 5 and 7F in two cohorts was observed. Furthermore, between very-low-birth-weight (VLBW) infants of <1500 g and 1501 ~ 2500 g, overall RRs of immune response to PCV-7 administration was 0.98 (95%CI: 0.96 ~ 1.00). CONCLUSIONS Preterm infants have a great tolerance to PCV-7, PCV-10 or PCV-13 vaccination. PCV-7 could elicit optimal immune response post vaccination in preterm infants, even in VLBW infants.
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Tashani M, Rashid H, Mulholland K, Booy R. Carrier priming to improve pneumococcal disease control and reduce the international program's cost in children. Pneumonia (Nathan) 2016; 8:16. [PMID: 28702295 PMCID: PMC5471833 DOI: 10.1186/s41479-016-0016-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/22/2016] [Indexed: 11/21/2022] Open
Abstract
Pneumococcal conjugate vaccine (PCV) has the potential to interact with other vaccines containing diphtheria toxin-like antigens (such as those found in the DTP vaccine) upon sequential administration. This is attributed to the similarity of the diphtheria toxoid antigen to the carrier protein used to make PCV, (known as cross reactive material [CRM]) to diphtheria toxin 197 or CRM197. The interaction could lead to enhanced immunogenicity of PCV as a result of a phenomenon called carrier priming, whereby DTP is given some weeks before the first dose of PCV. This phenomenon could be implemented in the immunisation schedule in developing countries and among vulnerable populations to enhance the immunogenicity of PCV, reduce the number of doses required, and produce a more cost-effective immunisation program in developing countries.
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Affiliation(s)
- Mohamed Tashani
- National Centre for Immunisation Research and Surveillance (NCIRS), The Children's Hospital at Westmead, Sydney, NSW Australia.,The Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NSW Australia.,NHMRC Centre for Research Excellence-Immunisation in understudied and special risk populations: closing the gap in knowledge through a multidisciplinary approach, School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Harunor Rashid
- National Centre for Immunisation Research and Surveillance (NCIRS), The Children's Hospital at Westmead, Sydney, NSW Australia.,The Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NSW Australia.,NHMRC Centre for Research Excellence-Immunisation in understudied and special risk populations: closing the gap in knowledge through a multidisciplinary approach, School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Sydney, Australia.,Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Biological Sciences and Sydney Medical School, University of Sydney, Sydney, Australia
| | - Kim Mulholland
- Murdoch Childrens Research Institute, Melbourne, VIC Australia.,London School of Hygiene and Tropical Medicine, London, UK
| | - Robert Booy
- National Centre for Immunisation Research and Surveillance (NCIRS), The Children's Hospital at Westmead, Sydney, NSW Australia.,The Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NSW Australia.,NHMRC Centre for Research Excellence-Immunisation in understudied and special risk populations: closing the gap in knowledge through a multidisciplinary approach, School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Sydney, Australia.,Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Biological Sciences and Sydney Medical School, University of Sydney, Sydney, Australia.,WHO Collaborating Centre for Mass Gatherings and High Consequence/High Visibility Events, Flinders University, Adelaide, 5001 Australia
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18
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Mokaddas E, Albert MJ. Serotype distribution and penicillin-non-susceptibility of Streptococcus pneumoniae causing invasive diseases in Kuwait: A 10-year study of impact of pneumococcal conjugate vaccines. Expert Rev Vaccines 2016; 15:1337-45. [PMID: 27267070 DOI: 10.1080/14760584.2016.1198698] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVES The impact of PCV7 and PCV13 on pneumococcal infections in Kuwait is not known. Therefore we evaluated the impact on pneumococcal serotype distribution and penicillin-non-susceptibility in invasive infections in Kuwait. METHODS Children < 2 y were given PCV7 from Aug 2006 to Jul 2010 (period I), and PCV13 from Aug 2010 to Jul 2013 (period II) with a pre-vaccination period from Aug 2003 to Jul 2006. Serotype and penicillin-non-susceptibility of blood and cerebrospinal fluid isolates from all ages were determined. RESULTS In <2 y old children, even with a small number of infections, a drop in PCV7 serotypes was evident after vaccination. For all age groups combined, in the pre-vaccination period, PCV7, PCV13, PCV13 non-PCV7 serotypes and penicillin-non-susceptibility constituted 53.2%, 72.6%, 19.4% and 6.5% of the isolates respectively. PCV7, PCV13 non-PCV7 serotypes and penicillin-non-susceptibility changed to 32.7%, 28.2% and 7.3% (period I) and 6.6%, 22.2% and 8.9% (period II). CONCLUSIONS Vaccines reduced invasive infections due to PCV7 serotypes.
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Affiliation(s)
- Eiman Mokaddas
- a Faculty of Medicine, Department of Microbiology , Kuwait University , Jabriya , Kuwait
| | - M John Albert
- a Faculty of Medicine, Department of Microbiology , Kuwait University , Jabriya , Kuwait
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19
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Ubukata K, Chiba N, Hanada S, Morozumi M, Wajima T, Shouji M, Iwata S. Serotype Changes and Drug Resistance in Invasive Pneumococcal Diseases in Adults after Vaccinations in Children, Japan, 2010-2013. Emerg Infect Dis 2016; 21:1956-65. [PMID: 26485679 PMCID: PMC4622236 DOI: 10.3201/eid2111.142029] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Pneumococcal conjugate vaccination of children is associated with penicillin-resistant Streptococcus pneumoniae in adults. After 7-valent pneumococcal conjugate vaccine (PCV) for children was introduced in Japan in November 2010, we examined changes in Streptococcus pneumoniae serotypes and in genetic antimicrobial drug resistance of isolates from adults with invasive pneumococcal diseases. During April 2010–March 2013, a total of 715 isolates were collected from adults with invasive pneumococcal diseases. Seven-valent PCV serotypes in adults decreased from 43.3% to 23.8%, most noticeably for serotype 6B. Concomitantly, 23-valent pneumococcal polysaccharide vaccine (PPSV23) serotypes decreased from 82.2% to 72.2%; non-PPSV23 serotypes increased from 13.8% to 25.1%. Parallel with serotype changes, genotypic penicillin-resistant S. pneumoniae decreased from 32.4% to 21.1%, and 6 non-PPSV23 serotypes emerged (6D, 15A, 15C, 16F, 23A, and 35B). Respective vaccine coverage rates for 13-valent PCV and PPSV23 differed by disease: 73.9% and 84.3% for patients with pneumonia, 56.4% and 69.2% for patients with bacteremia and sepsis, and 45.7% and 69.3% for patients with meningitis.
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20
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Ngo CC, Massa HM, Thornton RB, Cripps AW. Predominant Bacteria Detected from the Middle Ear Fluid of Children Experiencing Otitis Media: A Systematic Review. PLoS One 2016; 11:e0150949. [PMID: 26953891 PMCID: PMC4783106 DOI: 10.1371/journal.pone.0150949] [Citation(s) in RCA: 153] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 02/22/2016] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Otitis media (OM) is amongst the most common childhood diseases and is associated with multiple microbial pathogens within the middle ear. Global and temporal monitoring of predominant bacterial pathogens is important to inform new treatment strategies, vaccine development and to monitor the impact of vaccine implementation to improve progress toward global OM prevention. METHODS A systematic review of published reports of microbiology of acute otitis media (AOM) and otitis media with effusion (OME) from January, 1970 to August 2014, was performed using PubMed databases. RESULTS This review confirmed that Streptococcus pneumoniae and Haemophilus influenzae, remain the predominant bacterial pathogens, with S. pneumoniae the predominant bacterium in the majority reports from AOM patients. In contrast, H. influenzae was the predominant bacterium for patients experiencing chronic OME, recurrent AOM and AOM with treatment failure. This result was consistent, even where improved detection sensitivity from the use of polymerase chain reaction (PCR) rather than bacterial culture was conducted. On average, PCR analyses increased the frequency of detection of S. pneumoniae and H. influenzae 3.2 fold compared to culture, whilst Moraxella catarrhalis was 4.5 times more frequently identified by PCR. Molecular methods can also improve monitoring of regional changes in the serotypes and identification frequency of S. pneumoniae and H. influenzae over time or after vaccine implementation, such as after introduction of the 7-valent pneumococcal conjugate vaccine. CONCLUSIONS Globally, S. pneumoniae and H. influenzae remain the predominant otopathogens associated with OM as identified through bacterial culture; however, molecular methods continue to improve the frequency and accuracy of detection of individual serotypes. Ongoing monitoring with appropriate detection methods for OM pathogens can support development of improved vaccines to provide protection from the complex combination of otopathogens within the middle ear, ultimately aiming to reduce the risk of chronic and recurrent OM in vulnerable populations.
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Affiliation(s)
- Chinh C. Ngo
- School of Medical Science, Griffith University, Gold Coast, Queensland, Australia
- Molecular Basis of Disease, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Helen M. Massa
- School of Medical Science, Griffith University, Gold Coast, Queensland, Australia
- Molecular Basis of Disease, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
- * E-mail:
| | - Ruth B. Thornton
- School of Paediatrics and Child Health, University of Western Australia, Perth, Western Australia, Australia
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia, Australia
| | - Allan W. Cripps
- School of Medical Science, Griffith University, Gold Coast, Queensland, Australia
- Molecular Basis of Disease, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
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21
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Wu DBC, Chaiyakunapruk N, Chong HY, Beutels P. Choosing between 7-, 10- and 13-valent pneumococcal conjugate vaccines in childhood: a review of economic evaluations (2006-2014). Vaccine 2015; 33:1633-58. [PMID: 25681663 DOI: 10.1016/j.vaccine.2015.01.081] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 01/11/2015] [Accepted: 01/30/2015] [Indexed: 10/24/2022]
Abstract
BACKGROUND Seven-valent pneumococcal conjugate vaccines (PCV7) have been used in children for more than a decade. Given the observed increase in disease caused by pneumococcal serotypes not covered by PCV7, an increasing number of countries are switching from 7-valent to 10- and 13-valent PCVs ("PCV10" and "PCV13"). Economic evaluations are important tools to inform decisions and price negotiations to make such a switch. OBJECTIVE This review aims to provide a critical assessment of economic evaluations involving PCV10 or PCV13, published since 2006. METHODS We searched Scopus, ISI Web of Science (SCI and SSCI) and Pubmed to retrieve, select and review relevant studies, which were archived between 1st January 2006 and 31st January 2014. The review protocol involved standard extraction of assumptions, methods, results and sponsorships from the original studies. RESULTS Sixty-three economic evaluations on PCVs published since January 2006 were identified. About half of these evaluated PCV10 and/or PCV13, the subject of this review. At current prices, both PCV13 and PCV10 were likely judged preferable to PCV7. However, the combined uncertainty related to price differences, burden of disease, vaccine effectiveness, herd and serotype replacement effects determine the preference base for either PCV10 or PCV13. The pivotal assumptions and results of these analyses also depended on which manufacturer sponsored the study. CONCLUSION A more thorough exploration of uncertainty should be made in future analyses on this subject, as we lack understanding to adequately model herd and serotype replacement effects to reliably predict the population impact of PCVs. The introduction of further improved PCVs in an environment of evolving antibiotic resistance and under the continuing influence of previous PCVs implies that the complexity and data requirements for relevant analyses will further increase. Decision makers using these analyses should not just rely on an analysis from a single manufacturer.
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Affiliation(s)
| | - Nathorn Chaiyakunapruk
- School of Pharmacy, Monash University Malaysia, Malaysia; Department of Pharmacy Practice, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok, Thailand; School of Pharmacy, University of Wisconsin, Madison, USA; School of Population Health, University of Queensland, Brisbane, Australia.
| | - Huey-Yi Chong
- School of Pharmacy, Monash University Malaysia, Malaysia.
| | - Philippe Beutels
- Centre for Health Economics Research & Modelling Infectious Diseases, Vaccine & Infectious Disease Institute, WHO Collaborating Centre, Faculty of Medicine & Health Sciences, University of Antwerp, Belgium; School of Public Health and Community Medicine, The University of New South Wales, Sydney, Australia.
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Walls A, Pierce M, Krishnan N, Steehler M, Harley EH. Pediatric head and neck complications of Streptococcus pneumoniae before and after PCV7 vaccination. Otolaryngol Head Neck Surg 2014; 152:336-41. [PMID: 25385805 DOI: 10.1177/0194599814557777] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To discuss pediatric head and neck complications of pneumococcal infections before and after the introduction of the PCV7 vaccine. STUDY DESIGN Cross-sectional analysis of a national database. STUDY SETTING Kids National Inpatient Database. METHODS A retrospective review of the Kids National Inpatient Database yielded 31,738 pediatric reports involving complications of meningitis, mastoiditis, periorbital cellulitis, and Bezold abscesses due to Streptococcus pneumoniae diagnoses. Each report was analyzed for incidence, length of stay, mean hospital cost, and inpatient admittance from the emergency department. Finally, we calculated the expected annual incidence of each complication via variance-weighted analysis to determine the expected incidence if the vaccine was not administered. RESULTS We identified a significant decrease in the incidence of several complications after the introduction of the PCV7 vaccine and also when comparing these findings to our predicted incidence calculations if the vaccine was not administered. Inpatient admittance from the emergency department for Bezold abscess, periorbital cellulitis, mastoiditis, and meningitis was significantly increased in the pediatric age group (ages 1-4; P < .05). Furthermore, there was a significant increase in the cost to provide care for each of the described conditions (P < .05). CONCLUSIONS The PCV7 vaccine produced a measurable reduction in head and neck complications associated with S pneumoniae. However, our data suggest that these benefits were also met with increased inpatient admittance from the emergency department, hospital costs, and length of stay, each of which may be attributed to the selection of a more pathogenic subtype.
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Affiliation(s)
- Andrew Walls
- Georgetown University School of Medicine, Washington, DC
| | - Matthew Pierce
- Department of Otolaryngology-Head & Neck Surgery, Georgetown University Hospital, Washington, DC
| | | | - Matthew Steehler
- Ear, Nose, & Throat Associates of Corpus Christi, Otolaryngology-Head and Neck Surgery, Corpus Christi, Texas
| | - Earl H Harley
- Georgetown University School of Medicine, Washington, DC Department of Otolaryngology-Head & Neck Surgery and Pediatrics, Georgetown University Hospital, Washington, DC
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