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Malchrzak W, Babicki M, Pokorna-Kałwak D, Mastalerz-Migas A. The Influence of Introducing Free Vaccination against Streptococcus pneumoniae on the Uptake of Recommended Vaccination in Poland. Vaccines (Basel) 2023; 11:1838. [PMID: 38140242 PMCID: PMC10747999 DOI: 10.3390/vaccines11121838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/06/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023] Open
Abstract
Since 2017, pneumococcal vaccination has evolved from a recommended chargeable vaccination to a mandatory, and therefore free, vaccination for all children. While a 10-valent vaccine is commonly used, parents have the option to use a 13-valent vaccine for a fee. This study aimed to investigate whether and how the introduction of free pneumococcal vaccination affected the uptake of recommended vaccination and to assess the association of chargeable pneumococcal vaccination with recommended vaccination. Data from 1595 vaccination record cards kept by six primary care clinics in urban and rural areas of Poland were collected and analyzed for children born between 2015 and 2018. Belonging to the clinic and the year of birth were the only inclusion criteria. Following the introduction of free universal pneumococcal vaccination, more children were vaccinated with the recommended vaccination (61.2% vs. 66.6%, p = 0.026). The most significant change was in vaccination against rotavirus (48.5% vs. 54.4%, p = 0.018) and against meningococcal B bacteria (4.8% vs. 17.0%, p < 0.001). Children who received chargeable pneumococcal vaccination were also significantly more likely to be vaccinated with recommended vaccines (54.6% vs. 75.9%, p < 0.001). In particular, this was the case for multivalent vaccinations-against rotavirus, chickenpox, and meningococcal C bacteria. Reducing the impact of the economic factor, for example, by introducing free vaccinations, should have a positive impact on the uptake of other recommended vaccinations.
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Affiliation(s)
- Wojciech Malchrzak
- Department of Family Medicine, Faculty of Medicine, Wroclaw Medical University, 50-367 Wrocław, Poland; (M.B.); (D.P.-K.); (A.M.-M.)
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Sanchez CA, Rivera‐Lozada O, Lozada‐Urbano M, Best‐Bandenay P. Herd immunity in older adults from a middle-income country: A time-series trend analysis of community-acquired pneumonia mortality 2003-2017. Health Sci Rep 2023; 6:e1224. [PMID: 37152218 PMCID: PMC10155615 DOI: 10.1002/hsr2.1224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/20/2023] [Accepted: 04/03/2023] [Indexed: 05/09/2023] Open
Abstract
Background and Aims Community-acquired pneumonia is responsible for substantial mortality, and pneumococcus is commonly accepted as a major cause of pneumonia, regardless of laboratory confirmation. Child immunization programs have reported success in decreasing pneumonia mortality: directly in young children and indirectly (herd immunity) in unvaccinated adult populations in some countries. We assess changes in mortality trends for all-cause pneumonia in older adults associated with the introduction of pneumococcal vaccination for children in Peru. Methods This is a secondary analysis on administrative data collected periodically by the Peruvian Ministry of Health. An observational retrospective time series analysis was conducted using longitudinal population-based data from death certificates in Peru between 2003 and 2017. The time series includes 6 years before and 9 years after the introduction of the pneumococcal-conjugated vaccines in the national child immunization program in 2009. Monthly frequencies and annual rates for all-cause pneumonia deaths in children under 5 years of age and adults over 65 years of age are presented. Linear and quadratic trends are analyzed. Results Deaths among older adults accounted for 75.6% of all-cause pneumonia mortality in Peru, with 94.4% of these reporting "pneumonia due to unspecified organism" as the underlying cause of death. Comparing pre- and post-child immunization program periods, annual average mortality rates from unspecified pneumonia decreased by 22.7% in young children but increased by 19.6% in older adults. A linear trend model supports this overall tendency, but a quadratic curve explains the data better. Conclusion Pneumococcal-conjugated vaccines are developed using serotypes prevalent in selected countries from less common (invasive) pneumococcal disease and expected to prevent mortality worldwide from widespread (noninvasive) pneumonia. Our results do not support the presence of herd immunity from pneumococcal vaccination of children for community-acquired pneumonia in the increasingly ageing population of Peru. This should direct future research and could influence public health policy.
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Affiliation(s)
| | - Oriana Rivera‐Lozada
- South American Center for Education and Research in Public HealthUniversidad Norbert WienerLimaPeru
| | - Michelle Lozada‐Urbano
- South American Center for Education and Research in Public HealthUniversidad Norbert WienerLimaPeru
| | - Pablo Best‐Bandenay
- School of Public Health and AdministrationUniversidad Peruana Cayetano HerediaLimaPeru
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von Mollendorf C, Ulziibayar M, Gessner BD, Do LAH, Nguyen CD, Beavon R, Suuri B, Luvsantseren D, Narangerel D, Jenney A, Dunne EM, Satzke C, Darmaa B, Mungun T, Mulholland EK. Evaluation of the impact of childhood 13-valent pneumococcal conjugate vaccine introduction on adult pneumonia in Ulaanbaatar, Mongolia: study protocol for an observational study. BMC Public Health 2021; 21:1731. [PMID: 34556065 PMCID: PMC8460191 DOI: 10.1186/s12889-021-11776-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 09/13/2021] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Community-acquired pneumonia is an important cause of morbidity and mortality in adults. Approximately one-third of pneumonia cases can be attributed to the pneumococcus. Pneumococcal conjugate vaccines (PCVs) protect against colonisation with vaccine-type serotypes. The resulting decrease in transmission of vaccine serotypes leads to large indirect effects. There are limited data from developing countries demonstrating the impact of childhood PCV immunisation on adult pneumonia. There are also insufficient data available on the burden and severity of all-cause pneumonia and respiratory syncytial virus (RSV) in adults from low resource countries. There is currently no recommendation for adult pneumococcal vaccination with either pneumococcal polysaccharide vaccine or PCVs in Mongolia. We describe the protocol developed to evaluate the association between childhood 13-valent PCV (PCV13) vaccination and trends in adult pneumonia. METHODS PCV13 was introduced into the routine childhood immunisation schedule in Mongolia in a phased manner from 2016. In March 2019 we initiated active hospital-based surveillance for adult pneumonia, with the primary objective of evaluating trends in severe hospitalised clinical pneumonia incidence in adults 18 years and older in four districts of Ulaanbaatar. Secondary objectives include measuring the association between PCV13 introduction and trends in all clinically-defined pneumonia, radiologically-confirmed pneumonia, nasopharyngeal carriage of S. pneumoniae and pneumonia associated with RSV or influenza. Clinical questionnaires, nasopharyngeal swabs, urine samples and chest radiographs were collected from enrolled patients. Retrospective administrative and clinical data were collected for all respiratory disease-related admissions from January 2015 to February 2019. DISCUSSION Establishing a robust adult surveillance system may be an important component of monitoring the indirect impact of PCVs within a country. Monitoring indirect impact of childhood PCV13 vaccination on adult pneumonia provides additional data on the full public health impact of the vaccine, which has implications for vaccine efficiency and cost-effectiveness. Adult surveillance in Mongolia will contribute to the limited evidence available on the burden of pneumococcal pneumonia among adults in low- and middle-income countries, particularly in the Asia-Pacific region. In addition, it is one of the few examples of implementing prospective, population-based pneumonia surveillance to evaluate the indirect impact of PCVs in a resource-limited setting.
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Affiliation(s)
- Claire von Mollendorf
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia.
- Department of Paediatrics, The University of Melbourne, Parkville, Australia.
| | - Mukhchuluun Ulziibayar
- National Center for Communicable Diseases (NCCD), Ministry of Health, Ulaanbaatar, Mongolia
| | | | - Lien Anh Ha Do
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Australia
| | - Cattram D Nguyen
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Australia
| | | | - Bujinlkham Suuri
- National Center for Communicable Diseases (NCCD), Ministry of Health, Ulaanbaatar, Mongolia
| | | | | | - Adam Jenney
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia
- Department of Infectious Diseases, The Alfred Hospital, Monash University, Melbourne, Australia
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Eileen M Dunne
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Australia
- Pfizer Vaccines, Collegeville, PA, USA
| | - Catherine Satzke
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Australia
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Badarchiin Darmaa
- National Center for Communicable Diseases (NCCD), Ministry of Health, Ulaanbaatar, Mongolia
| | - Tuya Mungun
- National Center for Communicable Diseases (NCCD), Ministry of Health, Ulaanbaatar, Mongolia
| | - E Kim Mulholland
- Infection and Immunity, New Vaccines Research Group, Murdoch Children's Research Institute, Royal Children's Hospital, 50 Flemington Road, Parkville, VIC, 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Australia
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
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Wang BC, Chaiyakunapruk N, Zhu S, Babigumira JB, Furnback W, Chitale R, Gamil A, Zhao K, Wasserman M. A systematic literature review of economic evaluations of pneumococcal conjugate vaccines in east and southeast Asia (2006-2019). Expert Rev Vaccines 2021; 21:885-898. [PMID: 33682584 DOI: 10.1080/14760584.2021.1894933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Pneumococcal infections can lead to serious invasive diseases such as meningitis, septicemia and pneumonia, as well as milder but more common illnesses such as sinusitis and otitis media. The World Health Organization (WHO) recommends the inclusion of pneumococcal conjugate vaccines (PCVs) in infant National Immunization Program (NIP) programs worldwide. Decision-makers in Asian countries planning to introduce PCVs in their respective NIP will need a comprehensive evidence of effectiveness of PCVs at the population level and economic evidence including cost-effectiveness. AREAS COVERED A systematic literature review (from 1/1/2016 to 10/11/2019) of PCVs in East and Southeast Asia to understand (1) the contributing factors to cost-effectiveness results of PCVs and (2) whether gaps in evidence exist suggesting why the region may have yet to implement full NIPs. EXPERT OPINION In East and Southeast Asia, vaccination with PCVs was found to significantly reduce the mortality and morbidity of pneumococcal diseases and was cost-effective compared to no vaccination. Study assumptions, specifically vaccine local acquisition, the inclusion or exclusion of indirect effects (serotype replacement and herd effect), cross-protection, and protection against nontypeable haemophilus influenzae and serotype 3, were the main drivers of cost-effectiveness.
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Affiliation(s)
- Bruce Cm Wang
- Health Economics and Real World Evidence , Elysia Group, LLC, New York, NY, USA
| | | | - Shuiqing Zhu
- Health Economics and Outcomes Research, Pfizer Investment Co. Ltd, Shanghai, China
| | | | - Wesley Furnback
- Health Economics and Real World Evidence , Elysia Group, LLC, New York, NY, USA
| | - Ramaa Chitale
- Health Economics and Outcomes Research, Pfizer Inc, New York, NY, USA
| | - Amgad Gamil
- Medical and Scientific Affairs, Pfizer Inc, Singapore
| | - Kun Zhao
- Health Technology Assessment, China National Health Development Research Center, National Health Commission of the People's Republic of China
| | - Matt Wasserman
- Health Economics and Outcomes Research, Pfizer Inc, New York, NY, USA
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Bigogo GM, Audi A, Auko J, Aol GO, Ochieng BJ, Odiembo H, Odoyo A, Widdowson MA, Onyango C, Borgdorff MW, Feikin DR, Carvalho MDG, Whitney CG, Verani JR. Indirect Effects of 10-Valent Pneumococcal Conjugate Vaccine Against Adult Pneumococcal Pneumonia in Rural Western Kenya. Clin Infect Dis 2020; 69:2177-2184. [PMID: 30785189 DOI: 10.1093/cid/ciz139] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 02/11/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Data on pneumococcal conjugate vaccine (PCV) indirect effects in low-income countries with high human immunodeficiency virus (HIV) burden are limited. We examined adult pneumococcal pneumonia incidence before and after PCV introduction in Kenya in 2011. METHODS From 1 January 2008 to 31 December 2016, we conducted surveillance for acute respiratory infection (ARI) among ~12 000 adults (≥18 years) in western Kenya, where HIV prevalence is ~17%. ARI cases (cough or difficulty breathing or chest pain, plus temperature ≥38.0°C or oxygen saturation <90%) presenting to a clinic underwent blood culture and pneumococcal urine antigen testing (UAT). We calculated ARI incidence and adjusted for healthcare seeking. The proportion of ARI cases with pneumococcus detected among those with complete testing (blood culture and UAT) was multiplied by adjusted ARI incidence to estimate pneumococcal pneumonia incidence. RESULTS Pre-PCV (2008-2010) crude and adjusted ARI incidences were 3.14 and 5.30/100 person-years-observation (pyo), respectively. Among ARI cases, 39.0% (340/872) had both blood culture and UAT; 21.2% (72/340) had pneumococcus detected, yielding a baseline pneumococcal pneumonia incidence of 1.12/100 pyo (95% confidence interval [CI]: 1.0-1.3). In each post-PCV year (2012-2016), the incidence was significantly lower than baseline; with incidence rate ratios (IRRs) of 0.53 (95% CI: 0.31-0.61) in 2012 and 0.13 (95% CI: 0.09-0.17) in 2016. Similar declines were observed in HIV-infected (IRR: 0.13; 95% CI: 0.08-0.22) and HIV-uninfected (IRR: 0.10; 95% CI: 0.05-0.20) adults. CONCLUSIONS Adult pneumococcal pneumonia declined in western Kenya following PCV introduction, likely reflecting vaccine indirect effects. Evidence of herd protection is critical for guiding PCV policy decisions in resource-constrained areas.
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Affiliation(s)
- Godfrey M Bigogo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu.,Academic Medical Centre, University of Amsterdam, The Netherlands
| | - Allan Audi
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - Joshua Auko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - George O Aol
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - Benjamin J Ochieng
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - Herine Odiembo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - Arthur Odoyo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - Marc-Alain Widdowson
- Division of Global Health Protection, US Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Clayton Onyango
- Division of Global Health Protection, US Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Martien W Borgdorff
- Academic Medical Centre, University of Amsterdam, The Netherlands.,Division of Global Health Protection, US Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Daniel R Feikin
- US Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | | | - Jennifer R Verani
- Division of Global Health Protection, US Centers for Disease Control and Prevention, Nairobi, Kenya
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Root-Bernstein R. Age and Location in Severity of COVID-19 Pathology: Do Lactoferrin and Pneumococcal Vaccination Explain Low Infant Mortality and Regional Differences? Bioessays 2020; 42:e2000076. [PMID: 32869330 DOI: 10.1002/bies.202000076] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 07/17/2020] [Indexed: 12/21/2022]
Abstract
Two conundrums puzzle COVID-19 investigators: 1) morbidity and mortality is rare among infants and young children and 2) rates of morbidity and mortality exhibit large variances across nations, locales, and even within cities. It is found that the higher the rate of pneumococcal vaccination in a nation (or city) the lower the COVID-19 morbidity and mortality. Vaccination rates with Bacillus Calmette-Guerin, poliovirus, and other vaccines do not correlate with COVID-19 risks, nor do COVID-19 case or death rates correlate with number of people in the population with diabetes, obesity, or adults over 65. Infant protection may be due to maternal antibodies and antiviral proteins in milk such as lactoferrin that are known to protect against coronavirus infections. Subsequent protection might then be conferred (and correlate with) rates of Haemophilus influenzae type B (Hib) (universal in infants) and pneumococcal vaccination, the latter varying widely by geography among infants, at-risk adults, and the elderly. Also see the video abstract here https://youtu.be/GODBYRbPL00.
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Pirçon JY, Talarico CA, Bollaerts K, Hausdorff WP, Clarke CJ. The choice of analytical methodology can alter conclusions regarding herd effects of paediatric pneumococcal vaccination programmes. Vaccine 2018; 36:6933-6943. [DOI: 10.1016/j.vaccine.2018.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 09/25/2018] [Accepted: 10/02/2018] [Indexed: 10/28/2022]
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Drolet M, Bénard É, Jit M, Hutubessy R, Brisson M. Model Comparisons of the Effectiveness and Cost-Effectiveness of Vaccination: A Systematic Review of the Literature. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2018; 21:1250-1258. [PMID: 30314627 DOI: 10.1016/j.jval.2018.03.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/20/2018] [Accepted: 03/25/2018] [Indexed: 05/21/2023]
Abstract
OBJECTIVES To describe all published articles that have conducted comparisons of model-based effectiveness and cost-effectiveness results in the field of vaccination. Specific objectives were to 1) describe the methodologies used and 2) identify the strengths and limitations of the studies. METHODS We systematically searched MEDLINE and Embase databases for studies that compared predictions of effectiveness and cost-effectiveness of vaccination of two or more mathematical models. We categorized studies into two groups on the basis of their data source for comparison (previously published results or new simulation results) and performed a qualitative synthesis of study conclusions. RESULTS We identified 115 eligible articles (only 5% generated new simulations from the reviewed models) examining the effectiveness and cost-effectiveness of vaccination against 14 pathogens (69% of studies examined human papillomavirus, influenza, and/or pneumococcal vaccines). The goal of most of studies was to summarize evidence for vaccination policy decisions, and cost-effectiveness was the most frequent outcome examined. Only 33%, 25%, and 3% of studies followed a systematic approach to identify eligible studies, assessed the quality of studies, and performed a quantitative synthesis of results, respectively. A greater proportion of model comparisons using published studies followed a systematic approach to identify eligible studies and to assess their quality, whereas more studies using new simulations performed quantitative synthesis of results and identified drivers of model conclusions. Most comparative modeling studies concluded that vaccination was cost-effective. CONCLUSIONS Given the variability in methods used to conduct/report comparative modeling studies, guidelines are required to enhance their quality and transparency and to provide better tools for decision making.
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Affiliation(s)
- Mélanie Drolet
- Centre de recherche du CHU de Québec-Université Laval, Axe santé des populations et pratiques optimales en santé, Québec, Canada
| | - Élodie Bénard
- Centre de recherche du CHU de Québec-Université Laval, Axe santé des populations et pratiques optimales en santé, Québec, Canada
| | - Mark Jit
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK; Modelling and Economics Unit, Public Health England, London, UK
| | | | - Marc Brisson
- Centre de recherche du CHU de Québec-Université Laval, Axe santé des populations et pratiques optimales en santé, Québec, Canada; Université Laval, Québec, Canada; Department of Infectious Disease Epidemiology, Imperial College, London, UK.
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9
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Chan J, Nguyen CD, Lai JYR, Dunne EM, Andrews R, Blyth CC, Datta S, Fox K, Ford R, Hinds J, La Vincente S, Lehmann D, Lim R, Mungun T, Newton PN, Phetsouvanh R, Pomat WS, Xeuatvongsa A, von Mollendorf C, Dance DAB, Satzke C, Muholland K, Russell FM. Determining the pneumococcal conjugate vaccine coverage required for indirect protection against vaccine-type pneumococcal carriage in low and middle-income countries: a protocol for a prospective observational study. BMJ Open 2018; 8:e021512. [PMID: 29776921 PMCID: PMC5961565 DOI: 10.1136/bmjopen-2018-021512] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION Pneumococcal conjugate vaccines (PCVs) prevent disease through both direct protection of vaccinated individuals and indirect protection of unvaccinated individuals by reducing nasopharyngeal (NP) carriage and transmission of vaccine-type (VT) pneumococci. While the indirect effects of PCV vaccination are well described, the PCV coverage required to achieve the indirect effects is unknown. We will investigate the relationship between PCV coverage and VT carriage among undervaccinated children using hospital-based NP pneumococcal carriage surveillance at three sites in Asia and the Pacific. METHODS AND ANALYSIS We are recruiting cases, defined as children aged 2-59 months admitted to participating hospitals with acute respiratory infection in Lao People's Democratic Republic, Mongolia and Papua New Guinea. Thirteen-valent PCV status is obtained from written records. NP swabs are collected according to standard methods, screened using lytA qPCR and serotyped by microarray. Village-level vaccination coverage, for the resident communities of the recruited cases, is determined using administrative data or community survey. Our analysis will investigate the relationship between VT carriage among undervaccinated cases (indirect effects) and vaccine coverage using generalised estimating equations. ETHICS AND DISSEMINATION Ethical approval has been obtained from the relevant ethics committees at participating sites. The results are intended for publication in open-access peer-reviewed journals and will demonstrate methods suitable for low- and middle-income countries to monitor vaccine impact and inform vaccine policy makers about the PCV coverage required to achieve indirect protection.
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Affiliation(s)
- Jocelyn Chan
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Cattram D Nguyen
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jana Y R Lai
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
| | - Eileen M Dunne
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Ross Andrews
- Global & Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
- National Centre for Epidemiology & Population Health, Australian National University, Canberra, Australia
| | - Christopher C Blyth
- School of Medicine, University of Western Australia, Perth, Australia
- Department of Infectious Diseases, Princess Margaret Hospital, Perth, Australia
| | - Siddhartha Datta
- World Health Organization, Vientiane, Lao People’s Democratic Republic
| | - Kim Fox
- Regional Office for the Western Pacific, World Health Organization, Manila, Philippines
| | - Rebecca Ford
- Infection and Immunity Unit, Papua New Guinea Institute of Medical Research, Goroka, Eastern Highlands, Papua New Guinea
| | - Jason Hinds
- Institute for Infection and Immunity, St George’s, University of London, London, UK
- BUGS Bioscience, London Bioscience Innovation Centre, London, UK
| | - Sophie La Vincente
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
| | - Deborah Lehmann
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Ruth Lim
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
| | - Tuya Mungun
- National Center of Communicable Diseases (NCCD), Ministry of Health, Ulaanbaatar, Mongolia
| | - Paul N Newton
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMHWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
| | - Rattanaphone Phetsouvanh
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMHWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
| | - Willam S Pomat
- Infection and Immunity Unit, Papua New Guinea Institute of Medical Research, Goroka, Eastern Highlands, Papua New Guinea
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Anonh Xeuatvongsa
- National Immunization Programme, Ministry of Health, Vientiane, Lao People’s Democratic Republic
| | - Claire von Mollendorf
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - David A B Dance
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMHWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
| | - Catherine Satzke
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Kim Muholland
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Fiona M Russell
- Pneumococcal Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia
- Centre for International Child Health, Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
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10
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Holubar M, Stavroulakis MC, Maldonado Y, Ioannidis JPA, Contopoulos-Ioannidis D. Impact of vaccine herd-protection effects in cost-effectiveness analyses of childhood vaccinations. A quantitative comparative analysis. PLoS One 2017; 12:e0172414. [PMID: 28249046 PMCID: PMC5332092 DOI: 10.1371/journal.pone.0172414] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 01/20/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Inclusion of vaccine herd-protection effects in cost-effectiveness analyses (CEAs) can impact the CEAs-conclusions. However, empirical epidemiologic data on the size of herd-protection effects from original studies are limited. METHODS We performed a quantitative comparative analysis of the impact of herd-protection effects in CEAs for four childhood vaccinations (pneumococcal, meningococcal, rotavirus and influenza). We considered CEAs reporting incremental-cost-effectiveness-ratios (ICERs) (per quality-adjusted-life-years [QALY] gained; per life-years [LY] gained or per disability-adjusted-life-years [DALY] avoided), both with and without herd protection, while keeping all other model parameters stable. We calculated the size of the ICER-differences without vs with-herd-protection and estimated how often inclusion of herd-protection led to crossing of the cost-effectiveness threshold (of an assumed societal-willingness-to-pay) of $50,000 for more-developed countries or X3GDP/capita (WHO-threshold) for less-developed countries. RESULTS We identified 35 CEA studies (20 pneumococcal, 4 meningococcal, 8 rotavirus and 3 influenza vaccines) with 99 ICER-analyses (55 per-QALY, 27 per-LY and 17 per-DALY). The median ICER-absolute differences per QALY, LY and DALY (without minus with herd-protection) were $15,620 (IQR: $877 to $48,376); $54,871 (IQR: $787 to $115,026) and $49 (IQR: $15 to $1,636) respectively. When the target-vaccination strategy was not cost-saving without herd-protection, inclusion of herd-protection always resulted in more favorable results. In CEAs that had ICERs above the cost-effectiveness threshold without herd-protection, inclusion of herd-protection led to crossing of that threshold in 45% of the cases. This impacted only CEAs for more developed countries, as all but one CEAs for less developed countries had ICERs below the WHO-cost-effectiveness threshold even without herd-protection. In several analyses, recommendation for the adoption of the target vaccination strategy depended on the inclusion of the herd protection effect. CONCLUSIONS Inclusion of herd-protection effects in CEAs had a substantial impact in the estimated ICERs and made target-vaccination strategies more attractive options in almost half of the cases where ICERs were above the societal-willingness to pay threshold without herd-protection. More empirical epidemiologic data are needed to determine the size of herd-protection effects across diverse settings and also the size of negative vaccine effects, e.g. from serotype substitution.
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Affiliation(s)
- Marisa Holubar
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Maria Christina Stavroulakis
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai/ Elmhurst Hospital Center, New York, New York, United States of America
| | - Yvonne Maldonado
- Department of Pediatrics, Division of Pediatric Infectious Diseases and Department of Health Research and Policy, Senior Associate Dean for Faculty Development and Diversity, Stanford University School of Medicine, Stanford, California, United States of America
| | - John P. A. Ioannidis
- Stanford Prevention Research Center, Department of Medicine and Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California, United States of America
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, United States of America
| | - Despina Contopoulos-Ioannidis
- Department of Pediatrics, Division of Pediatric Infectious Diseases and Department of Health Research and Policy, Senior Associate Dean for Faculty Development and Diversity, Stanford University School of Medicine, Stanford, California, United States of America
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, United States of America
- * E-mail:
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Nieddu F, Moriondo M, De Vitis E, Ricci S, Indolfi G, Resti M, Vocale C, Landini MP, Sartor A, Azzari C. PCV13 serotype decrease in Italian adolescents and adults in the post-PCV13 era: Herd protection from children or secular trend? Vaccine 2017; 35:1544-1550. [DOI: 10.1016/j.vaccine.2017.01.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 10/20/2022]
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12
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Sartori AMC, Rozman LM, Decimoni TC, Leandro R, Novaes HMD, de Soárez PC. A systematic review of health economic evaluations of vaccines in Brazil. Hum Vaccin Immunother 2017; 13:1-12. [PMID: 28129026 DOI: 10.1080/21645515.2017.1282588] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND In Brazil, since 2005, the Ministry of Health requires Health Economic Evaluation (HEE) of vaccines for introduction into the National Immunization Program. OBJECTIVES To describe and analyze the full HEE on vaccines conducted in Brazil from 1980 to 2013. METHODS Systematic review of the literature. We searched multiple databases. Two researchers independently selected the studies and extracted the data. The methodological quality of individual studies was evaluated using CHEERS items. RESULTS Twenty studies were reviewed. The most evaluated vaccines were pneumococcal (25%) and HPV (15%). The most used types of HEE were cost-effectiveness analysis (45%) and cost-utility analysis (20%). The research question and compared strategies were stated in all 20 studies and the target population was clear in 95%. Nevertheless, many studies did not inform the perspective of analysis or data sources. CONCLUSIONS HEE of vaccines in Brazil has increased since 2008. However, the studies still have methodological deficiencies.
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Affiliation(s)
- Ana Marli Christovam Sartori
- a Departamento de Moléstias Infecciosas e Parasitárias , Faculdade de Medicina, Universidade de São Paulo , São Paulo , Brazil
| | - Luciana Martins Rozman
- b Departamento de Medicina Preventiva , Faculdade de Medicina, Universidade de São Paulo , São Paulo , Brazil
| | - Tassia Cristina Decimoni
- b Departamento de Medicina Preventiva , Faculdade de Medicina, Universidade de São Paulo , São Paulo , Brazil
| | - Roseli Leandro
- b Departamento de Medicina Preventiva , Faculdade de Medicina, Universidade de São Paulo , São Paulo , Brazil
| | | | - Patrícia Coelho de Soárez
- b Departamento de Medicina Preventiva , Faculdade de Medicina, Universidade de São Paulo , São Paulo , Brazil
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Sheppard C, Fry NK, Mushtaq S, Woodford N, Reynolds R, Janes R, Pike R, Hill R, Kimuli M, Staves P, Doumith M, Harrison T, Livermore DM. Rise of multidrug-resistant non-vaccine serotype 15A Streptococcus pneumoniae in the United Kingdom, 2001 to 2014. Euro Surveill 2016; 21:30423. [PMID: 28006650 PMCID: PMC5291132 DOI: 10.2807/1560-7917.es.2016.21.50.30423] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 08/17/2016] [Indexed: 11/20/2022] Open
Abstract
Conjugate vaccines have reduced pneumococcal disease in vaccinated children and unvaccinated adults, but non-vaccine serotypes are of concern, particularly if antibiotic resistant. We reviewed Streptococcus pneumoniae collected via: (i) the British Society for Antimicrobial Chemotherapy (BSAC) surveillances from 2001-2014; (ii) Public Health England's (PHE) invasive isolate surveillance from 2005-2014 and (iii) referral to PHE for resistance investigation from 2005-2014. Serotype 15A increased in all series, with many representatives showing triple resistance to macrolides, tetracyclines and penicillin. 15A was consistently among the 10 most prevalent serotypes from 2011 in PHE and BSAC invasive isolate/bacteraemia surveillance but never previously; 26-33% of these invasive 15A isolates had triple resistance. BSAC respiratory isolates were only serotyped in 2013/14 and 2014/15 (October to September); 15A was most prevalent serotype in both periods, comprising 9-11% of isolates, 38-48% of them with triple resistance. Serotype 15A represented 0-4% of S. pneumoniae referred to PHE for reference investigation annually until 2008 but rose to 29% (2013) and 32% (2014). Almost all multidrug-resistant 15A isolates were sequence type (ST) 63 variants, whereas susceptible 15A isolates were clonally diverse. The rise of serotype 15A suggests that pneumococcal conjugate vaccines will need ongoing adaptation.
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Affiliation(s)
- Carmen Sheppard
- Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, London, United Kingdom
| | - Norman K Fry
- Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, London, United Kingdom
| | - Shazad Mushtaq
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Neil Woodford
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Rosy Reynolds
- Southmead Hospital, Bristol, United Kingdom
- British Society for Antimicrobial Chemotherapy, Birmingham, United Kingdom
| | | | - Rachel Pike
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Robert Hill
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Maimuna Kimuli
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Peter Staves
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Michel Doumith
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - Timothy Harrison
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
| | - David M Livermore
- Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
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Azzari C, Cortimiglia M, Nieddu F, Moriondo M, Indolfi G, Mattei R, Zuliani M, Adriani B, Degl'Innocenti R, Consales G, Aquilini D, Bini G, Di Natale ME, Canessa C, Ricci S, de Vitis E, Mangone G, Bechini A, Bonanni P, Pasinato A, Resti M. Pneumococcal serotype distribution in adults with invasive disease and in carrier children in Italy: Should we expect herd protection of adults through infants' vaccination? Hum Vaccin Immunother 2016; 12:344-50. [PMID: 26647277 PMCID: PMC5049737 DOI: 10.1080/21645515.2015.1102811] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The 7-valent pneumococcal conjugate vaccine (PCV7) produced a significant herd protection in unvaccinated adult population mostly because of pneumococcus carriage decrease in vaccinated children. It is not known if the 13-valent pneumococcal vaccine can give similar effect on adults. Aims of the work were to evaluate whether the 6 additional serotypes are present in nasopharynx of children and serotype distribution in invasive pneumococcal infections (IPD) in adults. Realtime-PCR was used to evaluate pneumococcal serotypes in adults with confirmed IPD and in nasopharyngeal swabs (NP) from 629 children not vaccinated or vaccinated with PCV7 and resident in the same geographical areas. Two hundred twenty-one patients (116 males, median 67.9 years) with IPD were studied (pneumonia n = 103, meningitis n = 61 sepsis n = 50, other n = 7). Two hundred twelve were serotyped. The most frequent serotypes were 3, (31/212; 14.6%), 19A, (19/212; 9.0%), 12 (17/212; 8.0%), 7F, (14/212; 6.6%). In NP of children, the frequency of those serotypes causing over 50% of IPD in adults was very low, ranging from 0.48% for serotype 7F to 7.9% for serotype 19A. On the other side serotype 5, very frequent in NP (18.7%) caused <1% IPD. In conclusion serotypes causing IPD in adults are very rarely found in children NP. We suggest that herd protection obtainable with the additional 6 serotypes included in PCV13 may be more limited than that demonstrated with PCV7 in the past. In order to reduce the burden of disease in adults, adults should be offered a specific vaccination program with highly immunogenic PCV.
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Affiliation(s)
- Chiara Azzari
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Martina Cortimiglia
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Francesco Nieddu
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Maria Moriondo
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Giuseppe Indolfi
- b Pediatric Division; Anna Meyer Children's Hospital ; Florence , Italy
| | - Romano Mattei
- c Operative Unit of Chemical-Clinical and Microbiological Analysis; Campo di Marte Hospital; ASL2 Lucca , Italy
| | - Massimo Zuliani
- d Division of Hygiene and Public Health; Invasive Disease Prevention and Surveillance; Prevention Department; ASS5 Friuli , Italy
| | | | | | | | | | - Giancarlo Bini
- h Division of General Medicine 1; New Hospital ; Prato , Italy
| | | | - Clementina Canessa
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Silvia Ricci
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Elisa de Vitis
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Giusi Mangone
- a Division of Immunology; Section of Pediatrics ; Department of Health Sciences; University of Florence and Anna Meyer Children's Hospital ; Florence , Italy
| | - Angela Bechini
- j Department of Health Sciences ; University of Florence ; Florence , Italy
| | - Paolo Bonanni
- j Department of Health Sciences ; University of Florence ; Florence , Italy
| | - Angela Pasinato
- k Center for Research and Education of Family Pediatricians (CESPER) ; Padova , Italy
| | - Massimo Resti
- b Pediatric Division; Anna Meyer Children's Hospital ; Florence , Italy
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McNeil HC, Jefferies JMC, Clarke SC. Vaccine preventable meningitis in Malaysia: epidemiology and management. Expert Rev Anti Infect Ther 2016; 13:705-14. [PMID: 25962101 DOI: 10.1586/14787210.2015.1033401] [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: 01/13/2023]
Abstract
Worldwide bacterial meningitis accounts for more than one million cases and 135,000 deaths annually. Profound, lasting neurological complications occur in 9-25% of cases. This review confirms the greatest risk from bacterial meningitis is in early life in Malaysia. Much of the disease burden can be avoided by immunization, particularly against Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae. Despite inclusion of the Hib vaccine in the National Immunisation Programme and the licensure of pneumococcal vaccines, these two species are the main contributors to bacterial meningitis in Malaysia, with Neisseria meningitidis and Mycobacterium tuberculosis, causing a smaller proportion of disease. The high Hib prevalence may partly be due to dated, small-scale studies limiting the understanding of the current epidemiological situation. This highlights the need for larger, better quality surveillance from Malaysia to evaluate the success of Hib immunization and to help guide immunization policy for vaccines against S. pneumoniae and N. meningitidis.
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Affiliation(s)
- Hannah C McNeil
- University of Southampton Malaysia Campus, No.3, Persiaran Canselor 1, Kota Ilmu, Educity, Iskandar, 79200 Nusajaya, Johor, Malaysia
| | - Johanna M C Jefferies
- Faculty of Medicine and Institute of Life Sciences, University of Southampton, Southampton, UK
| | - Stuart C Clarke
- University of Southampton Malaysia Campus, No.3, Persiaran Canselor 1, Kota Ilmu, Educity, Iskandar, 79200 Nusajaya, Johor, Malaysia.,Faculty of Medicine and Institute of Life Sciences, University of Southampton, Southampton, UK
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16
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Scarbrough Lefebvre CD, Terlinden A, Standaert B. Dissecting the indirect effects caused by vaccines into the basic elements. Hum Vaccin Immunother 2015; 11:2142-57. [PMID: 26186100 PMCID: PMC4635729 DOI: 10.1080/21645515.2015.1052196] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Vaccination directly protects vaccinated individuals, but it also has the potential for indirectly protecting the unvaccinated in a population (herd protection). Unintended negative consequences such as the re-manifestation of infection, mainly expressed as age shifts, result from vaccination programs as well. We discuss the necessary conditions for achieving optimal herd protection (i.e., high quality vaccine-induced immunity, substantial effect on the force of infection, and appropriate vaccine coverage and distribution), as well as the conditions under which age shifts are likely to occur. We show examples to illustrate these effects. Substantial ambiguity in observing and quantifying these indirect vaccine effects makes accurate evaluation troublesome even though the nature of these outcomes may be critical for accurate assessment of the economic value when decision makers are evaluating a novel vaccine for introduction into a particular region or population group. More investigation is needed to identify and develop successful assessment methodologies for precisely analyzing these outcomes.
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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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Che D, Zhou H, He J, Wu B. Modeling the impact of the 7-valent pneumococcal conjugate vaccine in Chinese infants: an economic analysis of a compulsory vaccination. BMC Health Serv Res 2014; 14:56. [PMID: 24507480 PMCID: PMC3918139 DOI: 10.1186/1472-6963-14-56] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 01/28/2014] [Indexed: 11/10/2022] Open
Abstract
Background The purpose of this study was to compare, from a Chinese societal perspective, the projected health benefits, costs, and cost-effectiveness of adding pneumococcal conjugate heptavalent vaccine (PCV-7) to the routine compulsory child immunization schedule. Methods A decision-tree model, with data and assumptions adapted for relevance to China, was developed to project the health outcomes of PCV-7 vaccination (compared with no vaccination) over a 5-year period as well as a lifetime. The vaccinated birth cohort included 16,000,000 children in China. A 2 + 1 dose schedule at US$136.51 per vaccine dose was used in the base-case analysis. One-way sensitivity analysis was used to test the robustness of the model. The impact of a net indirect effect (herd immunity) was evaluated. Outcomes are presented in terms of the saved disease burden, costs, quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio. Results In a Chinese birth cohort, a PCV-7 vaccination program would reduce the number of pneumococcus-related infections by at least 32% and would prevent 2,682 deaths in the first 5 years of life, saving $1,190 million in total costs and gaining an additional 9,895 QALYs (discounted by 3%). The incremental cost per QALY was estimated to be $530,354. When herd immunity was taken into account, the cost per QALY was estimated to be $95,319. The robustness of the model was influenced mainly by the PCV-7 cost per dose, effectiveness herd immunity and incidence of pneumococcal diseases. With and without herd immunity, the break-even costs in China were $29.05 and $25.87, respectively. Conclusions Compulsory routine infant vaccination with PCV-7 is projected to substantially reduce pneumococcal disease morbidity, mortality, and related costs in China. However, a universal vaccination program with PCV-7 is not cost-effective at the willingness-to-pay threshold that is currently recommended for China by the World Health Organization.
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Affiliation(s)
| | | | | | - Bin Wu
- Medical Decision and Economic Group, Department of Pharmacy, Renji Hospital, affiliated with the School of Medicine, Shanghai Jiaotong University, Shanghai, China.
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The Health Economic Impact of Universal Infant Vaccination with the 10-Valent Pneumococcal Nontypeable Haemophilus influenzae Protein D Conjugate Vaccine as Compared with 13-Valent Pneumococcal Conjugate Vaccine in Hong Kong. Value Health Reg Issues 2013; 2:64-74. [DOI: 10.1016/j.vhri.2013.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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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: 113] [Impact Index Per Article: 9.4] [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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Licciardi PV, Toh ZQ, Dunne E, Wong SS, Mulholland EK, Tang M, Robins-Browne RM, Satzke C. Protecting against pneumococcal disease: critical interactions between probiotics and the airway microbiome. PLoS Pathog 2012; 8:e1002652. [PMID: 22685396 PMCID: PMC3369940 DOI: 10.1371/journal.ppat.1002652] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Paul V Licciardi
- Pneumococcal Research, Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Australia.
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Blank PR, Szucs TD. Cost-effectiveness of 13-valent pneumococcal conjugate vaccine in Switzerland. Vaccine 2012; 30:4267-75. [DOI: 10.1016/j.vaccine.2012.04.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 03/15/2012] [Accepted: 04/03/2012] [Indexed: 12/15/2022]
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23
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Hoshi SL, Kondo M, Okubo I. Economic evaluation of vaccination programme of 7-valent pneumococcal conjugate vaccine to the birth cohort in Japan. Vaccine 2012; 30:3320-8. [DOI: 10.1016/j.vaccine.2012.02.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 02/13/2012] [Accepted: 02/13/2012] [Indexed: 11/16/2022]
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Ibuka Y, Paltiel AD, Galvani AP. Impact of program scale and indirect effects on the cost-effectiveness of vaccination programs. Med Decis Making 2012; 32:442-6. [PMID: 22472916 DOI: 10.1177/0272989x12441397] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Yoko Ibuka
- Yale University School of Medicine, New Haven, CT, USA (YI, ADP, APG),Hitotsubashi University, Tokyo, Japan (YI)
| | - A David Paltiel
- Yale University School of Medicine, New Haven, CT, USA (YI, ADP, APG)
| | - Alison P Galvani
- Yale University School of Medicine, New Haven, CT, USA (YI, ADP, APG)
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25
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Wu DBC, Chang CJ, Huang YC, Wen YW, Wu CL, Fann CSJ. Cost-effectiveness analysis of pneumococcal conjugate vaccine in Taiwan: a transmission dynamic modeling approach. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2012; 15:S15-9. [PMID: 22265061 DOI: 10.1016/j.jval.2011.11.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
OBJECTIVES Streptococcus pneumoniae causes significant morbidity and mortality worldwide. Static pharmacoeconomic models have been used to conduct pharmacoeconomic analyses of pediatric pneumococcal conjugate vaccination programs. The objective of this study was to develop a transmission dynamic model to evaluate the cost-effectiveness of a 13-valent pneumococcal conjugate vaccine (PCV13) in Taiwan. METHODS An age-structured transmission dynamic model was populated with parameters from the Taiwanese National Health Insurance Research Database and publicly available sources to evaluate the clinical and economic impact of PCV13. Sensitivity analyses were performed to explore model uncertainties. RESULTS In the base-case analysis, four-dose scheduled universal infant PCV13 vaccination will prevent 5112 cases of invasive pneumococcal diseases, 535,607 cases of all-cause hospitalized pneumonia, 726,986 cases of acute otitis media, and 420 deaths over a 10-year time horizon since 2009. The four-dose vaccination program is estimated to yield an incremental cost-effectiveness ratio of US$38,045 and US$18,299 from payer and societal perspectives. One-way sensitivity analyses indicated that the incremental cost-effectiveness ratio is most sensitive to vaccine price. The 95% confidence interval of the incremental cost-effectiveness ratio was US$10,186 to US$34,563 by multivariate probabilistic sensitivity analyses in the societal perspective. CONCLUSIONS With a World Health Organization-recommended cost-effectiveness threshold, the PCV13 vaccination program would be cost-effective in Taiwan. To circumvent the lack of long-term real data, a transmission dynamic model is informative to decision makers on evaluating the long-term cost-effectiveness of PCV13.
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Affiliation(s)
- David Bin-Chia Wu
- Division of Biostatistics, Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
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26
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Robberstad B, Frostad CR, Akselsen PE, Kværner KJ, Berstad AK. Economic evaluation of second generation pneumococcal conjugate vaccines in Norway. Vaccine 2011; 29:8564-74. [DOI: 10.1016/j.vaccine.2011.09.025] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 08/31/2011] [Accepted: 09/08/2011] [Indexed: 10/17/2022]
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Díez-Domingo J, Ridao-López M, Gutiérrez-Gimeno MV, Puig-Barberá J, Lluch-Rodrigo JA, Pastor-Villalba E. Pharmacoeconomic assessment of implementing a universal PCV-13 vaccination programme in the Valencian public health system (Spain). Vaccine 2011; 29:9640-8. [PMID: 22027484 DOI: 10.1016/j.vaccine.2011.10.038] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 10/03/2011] [Accepted: 10/17/2011] [Indexed: 12/01/2022]
Abstract
BACKGROUND Heptavalent pneumococcal conjugate vaccine (PCV-7) was licensed to provide immunity against pneumococcal disease caused by seven serotypes of S. pneumoniae. Thirteen-valent pneumococcal conjugate vaccine (PCV-13) includes 6 additional serotypes for preventing invasive pneumococcal disease. OBJECTIVE The objective of this study was to estimate the potential health benefits, costs, and cost-effectiveness of vaccination with PCV-13 in the Community of Valencia and to generate valuable information for policy makers at regional and country levels. METHODS A decision tree was designed to determine the health and economic outcomes in hypothetical cohorts of vaccinated and unvaccinated children followed over their lifetime. Information about disease incidence and serotype distribution were gathered from local databases and from published and unpublished local records. PCV-13 effectiveness was extrapolated from PCV-7 efficacy data. A 5% of herd effect and a serotype replacement of 25% were considered for the base case scenario. Only direct costs were taken into account and results were expressed in terms of life-years gained (LYG) and quality adjusted life years (QALY). RESULTS Implementing a universal PCV-13 vaccination program in the Community of Valencia would decrease the number of hospital admitted pneumonia to less than 4571 cases while avoiding 310 cases of IPD and 82,596 cases of AOM throughout the cohort lifetime. A total of 190 S. pneumoniae related deaths would be averted over the same period. Total medical costs of non-vaccinating the cohort of newborns would reach up to 403,850.859€ compared to 438,762.712€ that would represent vaccinating the cohort. The incremental cost of vaccinating the children was estimated in 12,794€/LYG and 10,407€/QALY, respectively. CONCLUSIONS A universal PCV-13 vaccination program in the Community of Valencia would be a cost-effective intervention from the payer perspective after preventing for pneumococcal infections and for decreasing its associated mortality and morbidity.
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28
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Reply to Strutton et al.: Response to “Outcomes and costs associated with PHiD-CV, a new protein D conjugate pneumococcal vaccine, in four countries”. Vaccine 2011. [DOI: 10.1016/j.vaccine.2011.06.117] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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29
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Aljunid S, Abuduxike G, Ahmed Z, Sulong S, Nur AM, Goh A. Impact of routine PCV7 (Prevenar) vaccination of infants on the clinical and economic burden of pneumococcal disease in Malaysia. BMC Infect Dis 2011; 11:248. [PMID: 21936928 PMCID: PMC3189895 DOI: 10.1186/1471-2334-11-248] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 09/21/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pneumococcal disease is the leading cause of vaccine-preventable death in children younger than 5 years of age worldwide. The World Health Organization recommends pneumococcal conjugate vaccine as a priority for inclusion into national childhood immunization programmes. Pneumococcal vaccine has yet to be included as part of the national vaccination programme in Malaysia although it has been available in the country since 2005. This study sought to estimate the disease burden of pneumococcal disease in Malaysia and to assess the cost effectiveness of routine infant vaccination with PCV7. METHODS A decision model was adapted taking into consideration prevalence, disease burden, treatment costs and outcomes for pneumococcal disease severe enough to result in a hospital admission. Disease burden were estimated from the medical records of 6 hospitals. Where local data was unavailable, model inputs were obtained from international and regional studies and from focus group discussions. The model incorporated the effects of herd protection on the unvaccinated adult population. RESULTS At current vaccine prices, PCV7 vaccination of 90% of a hypothetical 550,000 birth cohort would incur costs of RM 439.6 million (US$128 million). Over a 10 year time horizon, vaccination would reduce episodes of pneumococcal hospitalisation by 9,585 cases to 73,845 hospitalisations with cost savings of RM 37.5 million (US$10.9 million) to the health system with 11,422.5 life years saved at a cost effectiveness ratio of RM 35,196 (US$10,261) per life year gained. CONCLUSIONS PCV7 vaccination of infants is expected to be cost-effective for Malaysia with an incremental cost per life year gained of RM 35,196 (US$10,261). This is well below the WHO's threshold for cost effectiveness of public health interventions in Malaysia of RM 71,761 (US$20,922).
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Affiliation(s)
- Syed Aljunid
- United Nations University-International Institute For Global Health, Kuala Lumpur, Malaysia.
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Abstract
Vaccine informatics is an emerging research area that focuses on development and applications of bioinformatics methods that can be used to facilitate every aspect of the preclinical, clinical, and postlicensure vaccine enterprises. Many immunoinformatics algorithms and resources have been developed to predict T- and B-cell immune epitopes for epitope vaccine development and protective immunity analysis. Vaccine protein candidates are predictable in silico from genome sequences using reverse vaccinology. Systematic transcriptomics and proteomics gene expression analyses facilitate rational vaccine design and identification of gene responses that are correlates of protection in vivo. Mathematical simulations have been used to model host-pathogen interactions and improve vaccine production and vaccination protocols. Computational methods have also been used for development of immunization registries or immunization information systems, assessment of vaccine safety and efficacy, and immunization modeling. Computational literature mining and databases effectively process, mine, and store large amounts of vaccine literature and data. Vaccine Ontology (VO) has been initiated to integrate various vaccine data and support automated reasoning.
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31
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Anonychuk A, Krahn M. Health economic and infectious disease modelling: a guide to merging streams. PHARMACOECONOMICS 2011; 29:367-9. [PMID: 21504238 DOI: 10.2165/11589240-000000000-00000] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Affiliation(s)
- Andrea Anonychuk
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
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32
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Outcomes and costs associated with PHiD-CV, a new protein D conjugate pneumococcal vaccine, in four countries. Vaccine 2010; 28 Suppl 6:G23-9. [DOI: 10.1016/j.vaccine.2010.06.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Coste-utilidad de la incorporación de las nuevas vacunas antineumocócicas conjugadas al programa de vacunación de la comunidad de Madrid. Impacto sobre la enfermedad neumocócica invasora. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/s1576-9887(10)70021-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Human communities defend themselves against specific infectious agents in a way that extends beyond the simple sum of the immune status of its individuals. By analogy with individual immunity to specific agents, the community level of immunity may vary from complete susceptibility to full protection. Herd immunity has been used to name this community property, which is the result of evolution through natural selection, leading to relationships between two species, typical of prey-predator systems. Varying uses of the term herd immunity led to the use of other expressions, such as herd protection, herd effect and community immunity. Knowledge derived from observational studies and models on herd immunity has supported decisions on the choice of vaccines and vaccination strategies for the benefit of populations. This knowledge is most likely to be extended in the future, with far-reaching effects.
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Affiliation(s)
- Guilherme Gonçalves
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University Porto, Largo Prof. Abel Salazar, n2, 4099-003 Porto, Portugal.
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