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Sauboin C, Mihajlović J, Postma MJ, Geets R, Antic D, Standaert B. Informing decision makers seeking to improve vaccination programs: case-study Serbia. J Mark Access Health Policy 2021; 9:1938894. [PMID: 34367530 PMCID: PMC8317957 DOI: 10.1080/20016689.2021.1938894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 06/13/2023]
Abstract
Background:The optimisation of vaccine policies before their implementation is beholden upon public health decision makers, seeking to maximise population health. In this case study in Serbia, the childhood vaccines under consideration included pneumococcal conjugate vaccination (PCV), rotavirus (RV) vaccination and varicella zoster virus (VZV) vaccination. Objective: The objective of this study is to define the optimal order of introduction of vaccines to minimise deaths, quality adjusted life years (QALYs) lost, or hospitalisation days, under budget and vaccine coverage constraints. Methods: A constrained optimisation model was developed including a static multi-cohort decision-tree model for the three infectious diseases. Budget and vaccine coverage were constrained, and to rank the vaccines, the optimal solution to the linear programming problem was based upon the ratio of the outcome (deaths, QALYs or hospitalisation days) per unit of budget. A probabilistic decision analysis Monte Carlo simulation technique was used to test the robustness of the rankings. Results: PCV was the vaccine ranked first to minimise deaths, VZV vaccination for QALY loss minimisation and RV vaccination for hospitalisation day reduction. Sensitivity analysis demonstrated the most robust ranking was that for PCV minimizing deaths. Conclusion: Constrained optimisation modelling, whilst considering all potential interventions currently, provided a comprehensive and rational approach to decision making.
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Affiliation(s)
- Christophe Sauboin
- Health Economics Department, GSK, Wavre, Belgium
- Department of Health Sciences, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
- Department of Economics, Econometrics & Finance, Faculty of Economics & Business, University of Groningen, Groningen, The Netherlands
| | - Jovan Mihajlović
- Department of Health Sciences, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
- Mihajlović Health Analytics (Miha), Novi Sad, Serbia
| | - Maarten Jacobus Postma
- Department of Health Sciences, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
- Department of Economics, Econometrics & Finance, Faculty of Economics & Business, University of Groningen, Groningen, The Netherlands
| | - Regine Geets
- Health Economics Department, GSK, Wavre, Belgium
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Standaert B, Sauboin C, Leclerc QJ, Connolly MP. Comparing the Analysis and Results of a Modified Social Accounting Matrix Framework with Conventional Methods of Reporting Indirect Non-Medical Costs. Pharmacoeconomics 2021; 39:257-269. [PMID: 33236330 PMCID: PMC7867525 DOI: 10.1007/s40273-020-00978-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/31/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Assessing the societal perspective in economic evaluations of new interventions requires estimates of indirect non-medical costs caused by the disease. Different methods exist for measuring the labor input function as a surrogate for these costs. They rarely specify the effect of health on labor and who gains and who loses money. Social accounting matrix (SAM) is an established framework that evaluates public policies with multiple perspectives that could help. OBJECTIVES We evaluated the use of a modified SAM to assess money flows between different economic agents resulting in economic transactions following policy changes of medical interventions. METHODS We compared conventional methods of measuring indirect non-medical costs related to rotavirus vaccination in the Netherlands with a modified SAM framework. To compare the outcome of each method, we calculated returns on investment (ROI) as the net amount of money per euro invested in the vaccine. One-way and probabilistic sensitivity analyses were carried out for each method, focusing on critical variables with the largest impact on indirect cost estimates. RESULTS The ROI was higher for the modified SAM (1.33) than for the conventional methods assessing income calculations (range - 0.178 to 1.22). Probabilistic sensitivity analyses showed wide distributions in the ROI estimates, with variation in the variable impact on the indirect cost results per method selected. CONCLUSIONS In contrast to conventional methods, the SAM approach provides detailed and comprehensive assessments of the impact of new interventions on the indirect non-medical costs and the financial interactions between agents, disclosing useful information for different stakeholders.
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Affiliation(s)
| | - Christophe Sauboin
- The University Medical Center Groningen, Groningen, The Netherlands
- Boehringer Ingelheim, Global Market Access Excellence, Ingelheim am Rhein, Germany
| | - Quentin J. Leclerc
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Mark P. Connolly
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Department of Pharmacy, University of Groningen, Groningen, The Netherlands
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Standaert B, Sauboin C, DeAntonio R, Marijam A, Gomez J, Varghese L, Zhang S. How to assess for the full economic value of vaccines? From past to present, drawing lessons for the future. J Mark Access Health Policy 2020; 8:1719588. [PMID: 32128075 PMCID: PMC7034472 DOI: 10.1080/20016689.2020.1719588] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 12/20/2019] [Accepted: 01/15/2020] [Indexed: 06/10/2023]
Abstract
Background:Cost-effectiveness analysis (CEA) is the economic analysis method most commonly applied today in the context of replacing one treatment with a new one in a developed healthcare system to improve efficiency. CEA is often requested by local healthcare decision-makers to grant reimbursement. New preventative interventions, such as new vaccines, may however have much wider benefits inside and outside healthcare, when compared with treatment. These additional benefits include externalities on indirect clinical impact, reallocation of specific healthcare resources, improved quality of care, better productivity, better disease control, better fiscal revenues, and others. But these effects are sometimes difficult to integrate into a meaningful CEA result. They may appear as specific benefits for specific stakeholders, other than the stakeholders in healthcare. Objective: Based on a historical view about the application of economic assessments for vaccines our objective has been to make the inventory of who was/is interested in knowing the economic value of vaccines, in what those different stakeholders are likely to see the benefit from their perspective and how were/are we able to measure those benefits and to report them well. Results: The historical view disclosed a limited interest in the economic assessment of vaccines at start, more than 50 years ago, that was comparable to the assessment of looking for more efficiency in new industries through optimization exercises. Today, we are exposed to a very rich panoply of different stakeholders (n= 16). They have their specific interest in many different facets of the vaccine benefit of which some are well known in the conventional economic analysis (n=9), but most outcomes are hidden and not enough evaluated and reported (n=26). Meanwhile we discovered that many different methods of evaluation have been explored to facilitate the measurement and reporting of the benefits (n=18). Conclusion: Our recommendation for future economic evaluations of new vaccines is therefore to find the right combination among the three entities of stakeholder type selection, outcome measure of interest for each stakeholder, and the right method to apply. We present at the end examples that illustrate how successful this approach can be.
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Affiliation(s)
| | | | | | - Alen Marijam
- Value Evidence and Outcome, GSK, Collegeville, PA, USA
| | - Jorge Gomez
- R&D Health Outcomes, GSK, Buenos Aires, Argentina
| | | | - Sharon Zhang
- Regional Health Outcomes, GSK, Singapore, Singapore
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Sicuri E, Yaya Bocoum F, Nonvignon J, Alonso S, Fakih B, Bonsu G, Kariuki S, Leeuwenkamp O, Munguambe K, Mrisho M, Were V, Sauboin C. The Costs of Implementing Vaccination With the RTS,S Malaria Vaccine in Five Sub-Saharan African Countries. MDM Policy Pract 2019; 4:2381468319896280. [PMID: 31903424 PMCID: PMC6923697 DOI: 10.1177/2381468319896280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 11/21/2019] [Indexed: 11/17/2022] Open
Abstract
Background. The World Health Organization has recommended pilot implementation of a candidate vaccine against malaria (RTS,S/AS01) in selected sub-Saharan African countries. This exploratory study aimed to estimate the costs of implementing RTS,S in Burkina Faso, Ghana, Kenya, Mozambique, and Tanzania. Methods. Key informants of the expanded program on immunization at all levels in each country were interviewed on the resources required for implementing RTS,S for routine vaccination. Unit prices were derived from the same sources or from international price lists. Incremental costs in 2015 US dollars were aggregated per fully vaccinated child (FVC). It was assumed the four vaccine doses were either all delivered at health facilities or the fourth dose was delivered in an outreach setting. Results. The costs per FVC ranged from US$25 (Burkina Faso) to US$37 (Kenya) assuming a vaccine price of US$5 per dose. Across countries, recurrent costs represented the largest share dominated by vaccines (including wastage) and supply costs. Non-recurrent costs varied substantially across countries, mainly because of differences in needs for hiring personnel, in wages, in cold-room space, and equipment. Recent vaccine introductions in the countries may have had an impact on resource availability for a new vaccine implementation. Delivering the fourth dose in outreach settings raised the costs, mostly fuel, per FVC by less than US$1 regardless of the country. Conclusions. This study provides relevant information for donors and decision makers about the cost of implementing RTS,S. Variations within and across countries are important and the unknown future price per dose and wastage rate for this candidate vaccine adds substantially to the uncertainty about the actual costs of implementation.
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Affiliation(s)
- Elisa Sicuri
- ISGlobal, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain
| | | | | | - Sergi Alonso
- ISGlobal, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain
| | - Bakar Fakih
- Ifakara Health Institute (IHI), Dar es Salaam, Tanzania
| | - George Bonsu
- Expanded Programme on Immunization, Ghana Health Service, Accra, Ghana
| | - Simon Kariuki
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | | | - Khatia Munguambe
- Centro de Investigação em Saúde da Manhiça (CISM), Manhiça, Mozambique
| | | | - Vincent Were
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
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Yerushalmi E, Hunt P, Hoorens S, Sauboin C, Smith R. Exploring the Use of a General Equilibrium Method to Assess the Value of a Malaria Vaccine: An Application to Ghana. MDM Policy Pract 2019; 4:2381468319894345. [PMID: 31903422 PMCID: PMC6923699 DOI: 10.1177/2381468319894345] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 11/05/2019] [Indexed: 01/16/2023] Open
Abstract
Background. Malaria is an important health and economic burden in
sub-Saharan Africa. Conventional economic evaluations typically consider only
direct costs to the health care system and government budgets. This paper
quantifies the potential impact of malaria vaccination on the wider economy,
using Ghana as an example. Methods. We used a computable general
equilibrium model of the Ghanaian economy to estimate the macroeconomic impact
of malaria vaccination in children under the age of 5, with a vaccine efficacy
of 50% against clinical malaria and 20% against malaria mortality. The model
considered changes in demography and labor productivity, and projected gross
domestic product (GDP) over a time frame of 30 years. Vaccine coverage ranging
from 20% to 100% was compared with a baseline with no vaccination.
Results. Malaria vaccination with 100% coverage was projected
to increase the GDP of Ghana over 30 years by US$6.93 billion (in 2015 prices)
above the baseline without vaccination, equivalent to an increase in annual GDP
growth of 0.5%. Projected GDP per capita would increase in the first year due to
immediate reductions in time lost from work by adults caring for children with
malaria, then decrease for several years as reductions in child mortality
increase the number of dependent children, then show a sustained increase after
Year 11 due to long-term productivity improvements in adults resulting from
fewer malaria episodes in childhood. Conclusion. Investing in
improving childhood health by vaccinating against malaria could result in
substantial long-term macroeconomic benefits when these children enter the
workforce as adults. These macroeconomic benefits are not captured by
conventional economic evaluations and constitute an important potential benefit
of vaccination.
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Affiliation(s)
- Erez Yerushalmi
- Birmingham City Business School, Birmingham City University, Birmingham, UK
| | | | | | | | - Richard Smith
- College of Medicine and Health, University of Exeter, Exeter, UK
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Sauboin C, Van Vlaenderen I, Van Bellinghen LA, Standaert B. Reducing Malaria Mortality at the Lowest Budget: An Optimization Tool for Selecting Malaria Preventative Interventions Applied to Ghana. MDM Policy Pract 2019; 4:2381468319861346. [PMID: 31384668 PMCID: PMC6659186 DOI: 10.1177/2381468319861346] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 04/14/2019] [Indexed: 11/18/2022] Open
Abstract
Background. Preventative malaria interventions include
long-lasting insecticidal nets (LLINs), indoor residual spraying (IRS), and
seasonal malaria chemoprevention (SMC). The RTS,S vaccine candidate is now also
approved for pilot introduction. This analysis estimates the optimal approach
when combining current interventions with the vaccine to reduce under-five
malaria mortality in Ghana at the lowest cost. Methods. A
vector model was combined with a static human cohort model, using
country-specific unit costs. Current coverage of each intervention was used as
baseline. The base-case vaccine price was US$5/dose, with US$2 or US$10 tested
in sensitivity analysis. Model simulations used a goal for extra mortality
reduction in children aged <5 years, and identified the optimal combination
of interventions to reach that goal at the lowest cost. The time horizon was 5
years. Results. The optimal sequence of investments would be
the following: (1) introduce RTS,S; (2) introduce SMC; (3) increase LLINs and
IRS concurrently. RTS,S introduction was associated with mortality reduction of
16% for a budget increase of US$15.6 million. Adding SMC with a partial coverage
of 4% further reduced mortality by 1% at an additional budget of US$1.4 million.
Subsequently scaling-up IRS, LLINs, and SMC at their maximum achievable coverage
further reduced mortality by 82% (total reduction 98%) at an additional budget
of US$474 million. At an RTS,S price of US$10/dose, SMC was first in the optimal
sequence. A lower RTS,S price maintained the sequence but reduced the budget
need. Conclusions. In Ghana, RTS,S introduction in addition to
the existing measures would be the optimal first step for reducing under-five
malaria mortality at the lowest cost, followed by SMC in relevant areas, and
then further scaling-up of IRS and LLINs.
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Brew J, Sauboin C. A Systematic Review of the Incremental Costs of Implementing a New Vaccine in the Expanded Program of Immunization in Sub-Saharan Africa. MDM Policy Pract 2019; 4:2381468319894546. [PMID: 31903423 PMCID: PMC6923695 DOI: 10.1177/2381468319894546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 11/16/2019] [Indexed: 01/07/2023] Open
Abstract
Background. The World Health Organization is planning a pilot introduction of a new malaria vaccine in three sub-Saharan African countries. To inform considerations about including a new vaccine in the vaccination program of those and other countries, estimates from the scientific literature of the incremental costs of doing so are important. Methods. A systematic review of scientific studies reporting the costs of recent vaccine programs in sub-Saharan countries was performed. The focus was to obtain from each study an estimate of the cost per dose of vaccine administered excluding the acquisition cost of the vaccine and wastage. Studies published between 2000 and 2018 and indexed on PubMed could be included and results were standardized to 2015 US dollars (US$). Results. After successive screening of 2119 titles, and 941 abstracts, 58 studies with 80 data points (combinations of country, vaccine type, and vaccination approach-routine v. campaign) were retained. Most studies used the so-called ingredients approach as costing method combining field data collection with documented unit prices per cost item. The categorization of cost items and the extent of detailed reporting varied widely. Across the studies, the mean and median cost per dose administered was US$1.68 and US$0.88 with an interquartile range of US$0.54 to US$2.31. Routine vaccination was more costly than campaigns, with mean cost per dose of US$1.99 and US$0.88, respectively. Conclusion. Across the studies, there was huge variation in the cost per dose delivered, between and within countries, even in studies using consistent data collection tools and analysis methods, and including many health facilities. For planning purposes, the interquartile range of US$0.54 to US$2.31 may be a sufficiently precise estimate.
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Affiliation(s)
- Joe Brew
- ISGlobal, Barcelona Ctr. Int. Health Res.
(CRESIB), Hospital Clínic—Universitat de Barcelona, Barcelona, Spain
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El-Houderi A, Constantin J, Castelnuovo E, Sauboin C. Economic and Resource Use Associated With Management of Malaria in Children Aged <5 Years in Sub-Saharan Africa: A Systematic Literature Review. MDM Policy Pract 2019; 4:2381468319893986. [PMID: 31903421 PMCID: PMC6927205 DOI: 10.1177/2381468319893986] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 11/05/2019] [Indexed: 11/30/2022] Open
Abstract
Background. Malaria is a major health, economic, and social burden in sub-Saharan Africa. Purpose. The objective is to help understanding the economic impact of malaria and informing estimates of the potential economic impact of malaria prevention. To achieve this, we conducted a systematic review of published information on health system costs, health care resource use, and household costs for the management of malaria episodes in children aged <5 years in sub-Saharan Africa. Data Sources and Study Selection. We conducted searches in Medline, EMBASE, and Cochrane Library for studies reporting data on economic cost or resource use associated with management of malaria in children aged <5 years in sub-Saharan Africa. Searches were limited to articles published in English or French between January 1, 2006, and September 1, 2016. Conference abstracts from 2014 to 2016 were hand-searched. Data Extraction and Data Synthesis. We identified 1846 publications, of which 17 met the selection criteria. The studies covered nine countries: The Democratic Republic of Congo, Ghana, Kenya, Malawi, Mozambique, Nigeria, Tanzania, Uganda, and Zambia. All costs were standardized to 2016 US dollars (US$). Seven studies estimated the costs of a malaria episode to health systems, and 10 publications plus one abstract reported household costs. The cost to the health system was US$1.94 to US$31.53 for outpatient malaria cases to US$20 to US$136 for inpatient cases. Families bear a large share of the burden through out-of-pocket payments of medical care and lost income due to time off work. Limitations. Data were missing for many countries and few comparisons could be made. Conclusions. Severe malaria is associated with much higher costs than uncomplicated malaria, and families bear a large share of the cost burden.
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Sauboin C, Van Bellinghen LA, Van De Velde N, Van Vlaenderen I. Economic Impact of Introducing the RTS,S Malaria Vaccine: Cost-Effectiveness and Budget Impact Analysis in 41 Countries. MDM Policy Pract 2019; 4:2381468319873324. [PMID: 31853505 PMCID: PMC6906355 DOI: 10.1177/2381468319873324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/27/2019] [Indexed: 11/25/2022] Open
Abstract
Background. Malaria is a major public health burden in sub-Saharan Africa. This study estimated the cost-effectiveness and budget impact of adding four-dose malaria vaccination in infants or children to existing interventions in 41 endemic countries in sub-Saharan Africa. Methods. A static Markov cohort model followed a simulated 2017 birth cohort (36.5 million children) for 15 years in 5-day cycles, comparing three strategies: child vaccination (doses at ages 6, 7.5, 9, and 27 months); infant vaccination (doses at ages 6, 10, and 14 weeks and 21 months); no malaria vaccination. The base-case analysis was conducted from the health system perspective with vaccine price assumed at USD5/dose and annual discounting of 3% for costs and disability-adjusted life-years (DALYs). Efficacy was based on the Phase III RTS,S clinical trial. Results. The model projected that 24.6 million children, or 26.2 million infants, would be vaccinated. Compared with no vaccination, child (infant) vaccination was projected to avert 16.8 million (16 million) cases of malaria and 113,000 (107,000) malaria deaths in the birth cohort over the 15-year period. The incremental cost-effectiveness ratio was USD200/DALY averted (USD225/DALY averted) for child (infant) vaccination, which represents 14% (17%) of the gross domestic product (GDP) per capita threshold. The estimated budget impact was overall larger for infant vaccination but mixed situations occurred across countries. Vaccine price, discount rate, and parasite prevalence had the largest effect on cost-effectiveness. Conclusions. Child vaccination with RTS,S would be more cost-effective than infant vaccination across countries. Adding RTS,S malaria vaccination to existing interventions would be cost-effective assuming one GDP per capita threshold for both child and infant vaccination in all examined countries except for 6 countries with lower transmission.
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Sauboin C, Holl K, Bonanni P, Gershon AA, Benninghoff B, Carryn S, Burgess MA, Wutzler P. The impact of childhood varicella vaccination on the incidence of herpes zoster in the general population: modelling the effect of exogenous and endogenous varicella-zoster virus immunity boosting. BMC Infect Dis 2019; 19:126. [PMID: 30727971 PMCID: PMC6366068 DOI: 10.1186/s12879-019-3759-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 01/29/2019] [Indexed: 12/30/2022] Open
Abstract
Background A controversy exists about the potential effect of childhood varicella vaccination on Herpes Zoster (HZ) incidence. Mathematical models projected temporary HZ incidence increase after vaccine introduction that was not confirmed by real-world evidence. These models assume that absence of contacts with infected children would prevent exogenous boosting of Varicella-Zoster-Virus (VZV) immunity and they do not include an endogenous VZV immunity-boosting mechanism following asymptomatic VZV reactivation. This study aims to explore the effect of various assumptions on exogenous and endogenous VZV immunity-boosting on HZ incidence in the general population after introduction of routine childhood varicella vaccination. Methods An age-structured dynamic transmission model was adapted and fitted to the seroprevalence of varicella in France in absence of vaccination using the empirical contact matrix. A two-dose childhood varicella vaccination schedule was introduced at 12 and 18 months. Vaccine efficacy was assumed at 65%/95% (dose 1/dose 2), and coverage at 90%/80% (dose 1/dose 2). Exogenous boosting intensity was based on assumptions regarding HZ-immunity duration, age-dependent boosting effect, and HZ reactivation rates fitted to observed HZ incidence. Endogenous boosting was the same as pre-vaccination exogenous boosting but constant over time, whilst exogenous boosting depended on the force of infection. Five scenarios were tested with different weightings of exogenous (Exo) - endogenous (Endo) boosting: 100%Exo–0%Endo, 75%Exo–25%Endo, 50%Exo–50%Endo, 25%Exo–75%Endo, 0%Exo–100%Endo. Results HZ incidence before varicella vaccination, all ages combined, was estimated at 3.96 per 1000 person-years; it decreased by 64% by year 80 post vaccine introduction, for all boosting assumptions. The 100%Exo-0%Endo boosting scenario, predicted an increase in HZ incidence for the first 21 years post vaccine introduction with a maximum increase of 3.7% (4.1/1000) at year 9. However, with 0%Exo-100%Endo boosting scenario an immediate HZ decline was projected. The maximum HZ incidence increases at 10, 3, and 2 years post vaccination were 1.8% (75%Exo-25%Endo), 0.8% (50%Exo-50%Endo) and 0.2% (25%Exo-75%Endo), respectively. Conclusions Assuming modest levels of endogenous boosting, the increase in HZ incidence following childhood varicella vaccination was smaller and lasted for a shorter period compared with 100%Exo-0%Endo boosting assumption. Endogenous boosting mechanism could partly explain the divergence between previous HZ-incidence projections and real-world evidence. Electronic supplementary material The online version of this article (10.1186/s12879-019-3759-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Katsiaryna Holl
- GSK Vaccines, Value Evidence, Wavre, Belgium.,Present address: Bayer AG, Epidemiology, Medical Affairs and Pharmacovigilance, Berlin, Germany
| | - Paolo Bonanni
- University of Florence, Health Sciences, Florence, Italy
| | | | | | | | | | - Peter Wutzler
- Department of Experimental Virology, University Hospital Jena, Jena, Germany
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Holl K, Sauboin C, Amodio E, Bonanni P, Gabutti G. Coverage, efficacy or dosing interval: which factor predominantly influences the impact of routine childhood vaccination for the prevention of varicella? A model-based study for Italy. BMC Public Health 2016; 16:1103. [PMID: 27769206 PMCID: PMC5073465 DOI: 10.1186/s12889-016-3738-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 09/30/2016] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Varicella is a highly infectious disease with a significant public health and economic burden, which can be prevented with childhood routine varicella vaccination. Vaccination strategies differ by country. Some factors are known to play an important role (number of doses, coverage, dosing interval, efficacy and catch-up programmes), however, their relative impact on the reduction of varicella in the population remains unclear. This paper aims to help policy makers prioritise the critical factors to achieve the most successful vaccination programme with the available budget. METHODS Scenarios assessed the impact of different vaccination strategies on reduction of varicella disease in the population. A dynamic transmission model was used and adapted to fit Italian demographics and population mixing patterns. Inputs included coverage, number of doses, dosing intervals, first-dose efficacy and availability of catch-up programmes, based on strategies currently used or likely to be used in different countries. The time horizon was 30 years. RESULTS Both one- and two-dose routine varicella vaccination strategies prevented a comparable number of varicella cases with complications, but two-doses provided broader protection due to prevention of a higher number of milder varicella cases. A catch-up programme in susceptible adolescents aged 10-14 years old reduced varicella cases by 27-43 % in older children, which are often more severe than in younger children. Coverage, for all strategies, sustained at high levels achieved the largest reduction in varicella. In general, a 20 % increase in coverage resulted in a further 27-31 % reduction in varicella cases. When high coverage is reached, the impact of dosing interval and first-dose vaccine efficacy had a relatively lower impact on disease prevention in the population. Compared to the long (11 years) dosing interval, the short (5 months) and medium (5 years) interval schedules reduced varicella cases by a further 5-13 % and 2-5 %, respectively. Similarly, a 10 % increase in first-dose efficacy (from 65 to 75 % efficacy) prevented 2-5 % more varicella cases, suggesting it is the least influential factor when considering routine varicella vaccination. CONCLUSIONS Vaccination strategies can be implemented differently in each country depending on their needs, infrastructure and healthcare budget. However, ensuring high coverage remains the critical success factor for significant prevention of varicella when introducing varicella vaccination in the national immunisation programme.
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Affiliation(s)
| | | | - Emanuele Amodio
- University of Palermo, Via Del Vespro 133, 90127, Palermo, Italy.,Present Address: Unit of Epidemiology, ATS Brianza, Viale Elvezia 2, 20900, Monza, Italy
| | - Paolo Bonanni
- University of Florence, Viale GB Morgagni, 48, 50134, Florence, Italy
| | - Giovanni Gabutti
- University of Ferrara, Via Fossato di Mortara 64b, 44121, Ferrara, Italy
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Penny MA, Verity R, Bever CA, Sauboin C, Galactionova K, Flasche S, White MT, Wenger EA, Van de Velde N, Pemberton-Ross P, Griffin JT, Smith TA, Eckhoff PA, Muhib F, Jit M, Ghani AC. Public health impact and cost-effectiveness of the RTS,S/AS01 malaria vaccine: a systematic comparison of predictions from four mathematical models. Lancet 2016; 387:367-375. [PMID: 26549466 PMCID: PMC4723722 DOI: 10.1016/s0140-6736(15)00725-4] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND The phase 3 trial of the RTS,S/AS01 malaria vaccine candidate showed modest efficacy of the vaccine against Plasmodium falciparum malaria, but was not powered to assess mortality endpoints. Impact projections and cost-effectiveness estimates for longer timeframes than the trial follow-up and across a range of settings are needed to inform policy recommendations. We aimed to assess the public health impact and cost-effectiveness of routine use of the RTS,S/AS01 vaccine in African settings. METHODS We compared four malaria transmission models and their predictions to assess vaccine cost-effectiveness and impact. We used trial data for follow-up of 32 months or longer to parameterise vaccine protection in the group aged 5-17 months. Estimates of cases, deaths, and disability-adjusted life-years (DALYs) averted were calculated over a 15 year time horizon for a range of levels of Plasmodium falciparum parasite prevalence in 2-10 year olds (PfPR2-10; range 3-65%). We considered two vaccine schedules: three doses at ages 6, 7·5, and 9 months (three-dose schedule, 90% coverage) and including a fourth dose at age 27 months (four-dose schedule, 72% coverage). We estimated cost-effectiveness in the presence of existing malaria interventions for vaccine prices of US$2-10 per dose. FINDINGS In regions with a PfPR2-10 of 10-65%, RTS,S/AS01 is predicted to avert a median of 93,940 (range 20,490-126,540) clinical cases and 394 (127-708) deaths for the three-dose schedule, or 116,480 (31,450-160,410) clinical cases and 484 (189-859) deaths for the four-dose schedule, per 100,000 fully vaccinated children. A positive impact is also predicted at a PfPR2-10 of 5-10%, but there is little impact at a prevalence of lower than 3%. At $5 per dose and a PfPR2-10 of 10-65%, we estimated a median incremental cost-effectiveness ratio compared with current interventions of $30 (range 18-211) per clinical case averted and $80 (44-279) per DALY averted for the three-dose schedule, and of $25 (16-222) and $87 (48-244), respectively, for the four-dose schedule. Higher ICERs were estimated at low PfPR2-10 levels. INTERPRETATION We predict a significant public health impact and high cost-effectiveness of the RTS,S/AS01 vaccine across a wide range of settings. Decisions about implementation will need to consider levels of malaria burden, the cost-effectiveness and coverage of other malaria interventions, health priorities, financing, and the capacity of the health system to deliver the vaccine. FUNDING PATH Malaria Vaccine Initiative; Bill & Melinda Gates Foundation; Global Good Fund; Medical Research Council; UK Department for International Development; GAVI, the Vaccine Alliance; WHO.
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Affiliation(s)
- Melissa A Penny
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
| | - Robert Verity
- Medical Research Council Centre for Outbreak Analysis and Modelling, Imperial College London, London, UK
| | | | | | - Katya Galactionova
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Stefan Flasche
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Michael T White
- Medical Research Council Centre for Outbreak Analysis and Modelling, Imperial College London, London, UK
| | | | | | - Peter Pemberton-Ross
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Jamie T Griffin
- Medical Research Council Centre for Outbreak Analysis and Modelling, Imperial College London, London, UK
| | - Thomas A Smith
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | | | | | - Mark Jit
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK; Modelling and Economics Unit, Public Health England, London, UK
| | - Azra C Ghani
- Medical Research Council Centre for Outbreak Analysis and Modelling, Imperial College London, London, UK
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Ouwens MJNM, Littlewood KJ, Sauboin C, Téhard B, Denis F, Boëlle PY, Alain S. The impact of 2-dose routine measles, mumps, rubella, and varicella vaccination in France on the epidemiology of varicella and zoster using a dynamic model with an empirical contact matrix. Clin Ther 2015; 37:816-829.e10. [PMID: 25726457 DOI: 10.1016/j.clinthera.2014.12.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/08/2014] [Accepted: 12/16/2014] [Indexed: 11/29/2022]
Abstract
PURPOSE Varicella has a high incidence affecting the vast majority of the population in France and can lead to severe complications. Almost every individual infected by varicella becomes susceptible to herpes zoster later in life due to reactivation of the latent virus. Zoster is characterized by pain that can be long-lasting in some cases and has no satisfactory treatment. Routine varicella vaccination can prevent varicella. The vaccination strategy of replacing both doses of measles, mumps, and rubella (MMR) with a combined MMR and varicella (MMRV) vaccine is a means of reaching high vaccination coverage for varicella immunization. The objective of this analysis was to assess the impact of routine varicella vaccination, with MMRV in place of MMR, on the incidence of varicella and zoster diseases in France and to assess the impact of exogenous boosting of zoster incidence, age shift in varicella cases, and other possible indirect effects. METHODS A dynamic transmission population-based model was developed using epidemiological data for France to determine the force of infection, as well as an empirically derived contact matrix to reduce assumptions underlying these key drivers of dynamic models. Scenario analyses tested assumptions regarding exogenous boosting, vaccine waning, vaccination coverage, risk of complications, and contact matrices. FINDINGS The model provides a good estimate of the incidence before varicella vaccination implementation in France. When routine varicella vaccination is introduced with French current coverage levels, varicella incidence is predicted to decrease by 57%, and related complications are expected to decrease by 76% over time. After vaccination, it is observed that exogenous boosting is the main driver of change in zoster incidence. When exogenous boosting is assumed, there is a temporary increase in zoster incidence before it gradually decreases, whereas without exogenous boosting, varicella vaccination leads to a gradual decrease in zoster incidence. Changing vaccine efficacy waning levels and coverage assumptions are still predicted to result in overall benefits with varicella vaccination. IMPLICATIONS In conclusion, the model predicted that MMRV vaccination can significantly reduce varicella incidence. With suboptimal coverage, a limited age shift of varicella cases is predicted to occur post-vaccination with MMRV. However, it does not result in an increase in the number of complications. GSK study identifier: HO-12-6924.
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Affiliation(s)
| | | | | | - Bertrand Téhard
- Pharmaco Epidemiology Unit, GSK France, Marly-le-Roi, France
| | - François Denis
- CHU de Limoges, Service de Bactériologie Virologie-Hygiène, Limoges, France
| | - Pierre-Yves Boëlle
- Université Pierre et Marie Curie, Service de Biostatistique - INSERM U707, Paris, France
| | - Sophie Alain
- CHU de Limoges, Service de Bactériologie Virologie-Hygiène, Limoges, France; Université de Limoges, Faculté de Médecine, Service de Bactériologie, INSERM UMR 1092, Limoges, France
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Littlewood KJ, Ouwens MJNM, Sauboin C, Tehard B, Alain S, Denis F. Cost-effectiveness of routine varicella vaccination using the measles, mumps, rubella and varicella vaccine in France: an economic analysis based on a dynamic transmission model for varicella and herpes zoster. Clin Ther 2015; 37:830-841.e7. [PMID: 25721380 DOI: 10.1016/j.clinthera.2015.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/11/2014] [Accepted: 01/16/2015] [Indexed: 11/28/2022]
Abstract
PURPOSE Each year in France, varicella and zoster affect large numbers of children and adults, resulting in medical visits, hospitalizations for varicella- and zoster-related complications, and societal costs. Disease prevention by varicella vaccination is feasible, wherein a plausible option involves replacing the combined measles, mumps, and rubella (MMR) vaccine with the combined MMR and varicella (MMRV) vaccine. This study aimed to: (1) assess the cost-effectiveness of adding routine varicella vaccination through MMRV, using different vaccination strategies in France; and (2) address key uncertainties, such as the economic consequences of breakthrough varicella cases, the waning of vaccine-conferred protection, vaccination coverage, and indirect costs. METHODS Based on the outputs of a dynamic transmission model that used data on epidemiology and costs from France, a cost-effectiveness model was built. A conservative approach was taken regarding the impact of varicella vaccination on zoster incidence by assuming the validity of the hypothesis of an age-specific boosting of immunity against varicella. FINDINGS The model determined that routine MMRV vaccination is expected to be a cost-effective option, considering a cost-effectiveness threshold of €20,000 per quality-adjusted life-year saved; routine vaccination was cost-saving from the societal perspective. Results were driven by a large decrease in varicella incidence despite a temporary initial increase in the number of zoster cases due to the assumption of exogenous boosting. In the scenario analyses, despite moderate changes in assumptions about incidence and costs, varicella vaccination remained a cost-effective option for France. IMPLICATIONS Routine vaccination with MMRV was associated with high gains in quality-adjusted life-years, substantial reduction in the occurrences of varicella- and zoster-related complications, and few deaths due to varicella. Routine MMRV vaccination is also expected to provide reductions in costs related to hospitalizations, medication use, and general-practitioner visits, as well as indirect costs, and it is expected to be a cost-effective intervention in France (GSK study identifier: HO-12-6924).
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Affiliation(s)
| | | | | | - Bertrand Tehard
- Pharmaco Epidemiology Unit, GSK France, Marly-le-Roi, France
| | - Sophie Alain
- University of Limoges, Faculty of Medicine, Bacteriology-Virology Service, Limoges, France
| | - François Denis
- CHU of Limoges, Bacteriology-Virology Hygiene Service, Limoges, France
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Sauboin C, Holl K, Amodio E, Bonanni P, Gabutti G, Vitale F. Coverage or Efficacy: Which Factor is the Most Influential for Reducing Varicella with Routine Childhood Vaccination in Italy? Value Health 2014; 17:A683-A684. [PMID: 27202530 DOI: 10.1016/j.jval.2014.08.2554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- C Sauboin
- GlaxoSmithKline Vaccines, Wavre, Belgium
| | - K Holl
- GlaxoSmithKline Vaccines, Wavre, Belgium
| | - E Amodio
- University of Palermo, Palermo, Italy
| | - P Bonanni
- University of florence, Florence, Italy
| | - G Gabutti
- University of Ferrara, Ferrara, Italy
| | - F Vitale
- University of Palermo, Palermo, Italy
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Sicuri E, Vieta A, Lindner L, Constenla D, Sauboin C. The economic costs of malaria in children in three sub-Saharan countries: Ghana, Tanzania and Kenya. Malar J 2013; 12:307. [PMID: 24004482 PMCID: PMC3844618 DOI: 10.1186/1475-2875-12-307] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 08/21/2013] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Malaria causes significant mortality and morbidity in sub-Saharan Africa (SSA), especially among children less than five years of age (U5 children). Although the economic burden of malaria in this region has been assessed previously, the extent and variation of this burden remains unclear. This study aimed to estimate the economic costs of malaria in U5 children in three countries (Ghana, Tanzania and Kenya). METHODS Health system and household costs previously estimated were integrated with costs associated with co-morbidities, complications and productivity losses due to death. Several models were developed to estimate the expected treatment cost per episode per child, across different age groups, by level of severity and with or without controlling for treatment-seeking behaviour. Total annual costs (2009) were calculated by multiplying the treatment cost per episode according to severity by the number of episodes. Annual health system prevention costs were added to this estimate. RESULTS Household and health system costs per malaria episode ranged from approximately US$ 5 for non-complicated malaria in Tanzania to US$ 288 for cerebral malaria with neurological sequelae in Kenya. On average, up to 55% of these costs in Ghana and Tanzania and 70% in Kenya were assumed by the household, and of these costs 46% in Ghana and 85% in Tanzania and Kenya were indirect costs. Expected values of potential future earnings (in thousands) lost due to premature death of children aged 0-1 and 1-4 years were US$ 11.8 and US$ 13.8 in Ghana, US$ 6.9 and US$ 8.1 in Tanzania, and US$ 7.6 and US$ 8.9 in Kenya, respectively. The expected treatment costs per episode per child ranged from a minimum of US$ 1.29 for children aged 2-11 months in Tanzania to a maximum of US$ 22.9 for children aged 0-24 months in Kenya. The total annual costs (in millions) were estimated at US$ 37.8, US$ 131.9 and US$ 109.0 nationwide in Ghana, Tanzania and Kenya and included average treatment costs per case of US$ 11.99, US$ 6.79 and US$ 20.54, respectively. CONCLUSION This study provides important insight into the economic burden of malaria in SSA that may assist policy makers when designing future malaria control interventions.
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Affiliation(s)
- Elisa Sicuri
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - Ana Vieta
- Health Economics and Outcome Research - IMS Health, Barcelona, Spain
| | - Leandro Lindner
- Health Economics and Outcome Research - IMS Health, Barcelona, Spain
| | - Dagna Constenla
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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