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Examining decentralization and managerial decision making for child immunization program performance in India. Soc Sci Med 2023; 317:115457. [PMID: 36493499 PMCID: PMC9870749 DOI: 10.1016/j.socscimed.2022.115457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 09/03/2022] [Accepted: 10/09/2022] [Indexed: 11/05/2022]
Abstract
Despite widespread adoption of decentralization reforms, the impact of decentralization on health system attributes, such as access to health services, responsiveness to population health needs, and effectiveness in affecting health outcomes, remains unclear. This study examines how decision space, institutional capacities, and accountability mechanisms of the Intensified Mission Indradhanush (IMI) in India relate to measurable performance of the immunization program. Data on decision space and its related dimensions of institutional capacity and accountability were collected by conducting structured interviews with managers based in 24 districts, 61 blocks, and 279 subcenters. Two measures by which to assess performance were selected: (1) proportion reduction in the DTP3 coverage gap (i.e., effectiveness), and (2) total IMI doses delivered per incremental USD spent on program implementation (i.e., efficiency). Descriptive statistics on decision space, institutional capacity, and accountability for IMI managers were generated. Structural equation models (SEM) were specified to detect any potential associations between decision space dimensions and performance measures. The majority of districts and blocks indicated low levels of decision space. Institutional capacity and accountability were similar across areas. Increases in decision space were associated with less progress towards closing the immunization coverage gap in the IMI context. Initiatives to support health workers and managers based on their specific contextual challenges could further improve outcomes of the program. Similar to previous studies, results revealed strong associations between each of the three decentralization dimensions. Health systems should consider the impact that management structures have on the efficiency and effectiveness of health services delivery. Future research could provide greater evidence for directionality of direct and indirect effects, interaction effects, and/or mediators of relationships.
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Utilization patterns, outcomes and costs of a simplified acute malnutrition treatment programme in Burkina Faso. MATERNAL & CHILD NUTRITION 2022; 18:e13291. [PMID: 34957682 PMCID: PMC8932691 DOI: 10.1111/mcn.13291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 10/11/2021] [Accepted: 10/12/2021] [Indexed: 12/01/2022]
Abstract
Access to treatment for acute malnutrition remains a challenge, in part due to the fragmentation of treatment programmes based on case severity. This paper evaluates utilization patterns, outcomes and associated costs for treating acute malnutrition cases among a cohort of children in Burkina Faso. This study is a secondary analysis of a proof‐of‐concept trial, called Optimizing treatment for acute Malnutrition (OptiMA), conducted in Burkina Faso in 2016. A total of 4958 eligible children whose mid‐upper arm circumference (MUAC) was less than 125 mm or with oedema were followed weekly and given ready‐to‐use therapeutic foods (RUTF). We evaluated the service utilization and outcomes among patients and estimated resource use and variable cost per patient, and examined factors driving variation in resource use. Children with lower initial MUAC level grew faster but required more time to recover than those with higher initial MUAC level. They also had higher rates of death, default and nonresponse. The simplified OptiMA approach for treating acute malnutrition achieved high rates of recovery overall (84%), especially among less severe cases, with modest quantities of RUTF. The average overall variable cost per child admitted was US$38.0 (SD: 20.5) half of which was accounted for by the cost of RUTF. Cost per recovered case was correlated with case severity, ranging from US$35.1 to US$132.8. If simplified integrated programmes using severity‐based RUTF dosing can increase access to treatment at earlier, less severe stages of acute malnutrition, they can help avoid more serious and costlier cases. This paper evaluates utilization patterns, outcomes, and associated costs for treating acute malnutrition cases among a cohort of children in Burkina Faso. Children with lower initial mid upper arm circumference (MUAC) level grew faster but required more time to recover than those with higher initial MUAC level. The average cost per child admitted was US$38.0 half of which was accounted for by the cost of ready to use therapeutic foods (RUTF). If simplified programs can increase access to treatment at earlier, less severe stages of acute malnutrition, they can help avoid more serious and costlier cases.
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WHO-led consensus statement on vaccine delivery costing: process, methods, and findings. BMC Med 2022; 20:88. [PMID: 35255920 PMCID: PMC8902809 DOI: 10.1186/s12916-022-02278-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 01/27/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Differences in definitions and methodological approaches have hindered comparison and synthesis of economic evaluation results across multiple health domains, including immunization. At the request of the World Health Organization's (WHO) Immunization and Vaccines-related Implementation Research Advisory Committee (IVIR-AC), WHO convened an ad hoc Vaccine Delivery Costing Working Group, comprising experts from eight organizations working in immunization costing, to address a lack of standardization and gaps in definitions and methodological guidance. The aim of the Working Group was to develop a consensus statement harmonizing terminology and principles and to formulate recommendations for vaccine delivery costing for decision making. This paper discusses the process, findings of the review, and recommendations in the Consensus Statement. METHODS The Working Group conducted several interviews, teleconferences, and one in-person meeting to identify groups working in vaccine delivery costing as well as existing guidance documents and costing tools, focusing on those for low- and middle-income country settings. They then reviewed the costing aims, perspectives, terms, methods, and principles in these documents. Consensus statement principles were drafted to align with the Global Health Cost Consortium costing guide as an agreed normative reference, and consensus definitions were drafted to reflect the predominant view across the documents reviewed. RESULTS The Working Group identified four major workstreams on vaccine delivery costing as well as nine guidance documents and eleven costing tools for immunization costing. They found that some terms and principles were commonly defined while others were specific to individual workstreams. Based on these findings and extensive consultation, recommendations to harmonize differences in terminology and principles were made. CONCLUSIONS Use of standardized principles and definitions outlined in the Consensus Statement within the immunization delivery costing community of practice can facilitate interpretation of economic evidence by global, regional, and national decision makers. Improving methodological alignment and clarity in program costing of health services such as immunization is important to support evidence-based policies and optimal resource allocation. On the other hand, this review and Consensus Statement development process revealed the limitations of our ability to harmonize given that study designs will vary depending upon the policy question that is being addressed and the country context.
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Tanzania HIV Investment Case (IC) 2.0: Using modeling to explore optimization under severe resource constraints. JOURNAL OF GLOBAL HEALTH REPORTS 2022. [DOI: 10.29392/001c.30063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Lives saved with vaccination for 10 pathogens across 112 countries in a pre-COVID-19 world. eLife 2021; 10:e67635. [PMID: 34253291 PMCID: PMC8277373 DOI: 10.7554/elife.67635] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/26/2021] [Indexed: 12/12/2022] Open
Abstract
Background Vaccination is one of the most effective public health interventions. We investigate the impact of vaccination activities for Haemophilus influenzae type b, hepatitis B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, rotavirus, rubella, Streptococcus pneumoniae, and yellow fever over the years 2000-2030 across 112 countries. Methods Twenty-one mathematical models estimated disease burden using standardised demographic and immunisation data. Impact was attributed to the year of vaccination through vaccine-activity-stratified impact ratios. Results We estimate 97 (95%CrI[80, 120]) million deaths would be averted due to vaccination activities over 2000-2030, with 50 (95%CrI[41, 62]) million deaths averted by activities between 2000 and 2019. For children under-5 born between 2000 and 2030, we estimate 52 (95%CrI[41, 69]) million more deaths would occur over their lifetimes without vaccination against these diseases. Conclusions This study represents the largest assessment of vaccine impact before COVID-19-related disruptions and provides motivation for sustaining and improving global vaccination coverage in the future. Funding VIMC is jointly funded by Gavi, the Vaccine Alliance, and the Bill and Melinda Gates Foundation (BMGF) (BMGF grant number: OPP1157270 / INV-009125). Funding from Gavi is channelled via VIMC to the Consortium's modelling groups (VIMC-funded institutions represented in this paper: Imperial College London, London School of Hygiene and Tropical Medicine, Oxford University Clinical Research Unit, Public Health England, Johns Hopkins University, The Pennsylvania State University, Center for Disease Analysis Foundation, Kaiser Permanente Washington, University of Cambridge, University of Notre Dame, Harvard University, Conservatoire National des Arts et Métiers, Emory University, National University of Singapore). Funding from BMGF was used for salaries of the Consortium secretariat (authors represented here: TBH, MJ, XL, SE-L, JT, KW, NMF, KAMG); and channelled via VIMC for travel and subsistence costs of all Consortium members (all authors). We also acknowledge funding from the UK Medical Research Council and Department for International Development, which supported aspects of VIMC's work (MRC grant number: MR/R015600/1).JHH acknowledges funding from National Science Foundation Graduate Research Fellowship; Richard and Peggy Notebaert Premier Fellowship from the University of Notre Dame. BAL acknowledges funding from NIH/NIGMS (grant number R01 GM124280) and NIH/NIAID (grant number R01 AI112970). The Lives Saved Tool (LiST) receives funding support from the Bill and Melinda Gates Foundation.This paper was compiled by all coauthors, including two coauthors from Gavi. Other funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. All authors had full access to all the data in the study and had final responsibility for the decision to submit for publication.
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Role of data from cost and other economic analyses in healthcare decision-making for HIV, TB and sexual/reproductive health programmes in South Africa. Health Policy Plan 2021; 36:1545-1551. [PMID: 34212192 PMCID: PMC8597963 DOI: 10.1093/heapol/czab071] [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: 02/11/2021] [Revised: 05/23/2021] [Accepted: 06/13/2021] [Indexed: 11/19/2022] Open
Abstract
An increasing focus on the use of the results of cost analyses and other economic evaluations in health programme decision-making by governments, donors and technical support partners working in low- and middle-income countries is accompanied by recognition that this use is impeded by several factors, including the lack of skills, data and coordination between spheres of the government. We describe our experience generating economic evaluation data for human immunodeficiency virus, tuberculosis and sexual/reproductive health programmes in South Africa alongside the results of a series of in-depth interviews (IDIs) among decision-makers within the South African government and implementing organizations (data users) and producers of economic evaluations (data producers). We summarize results across (1) the process of implementing a new intervention; (2) barriers to the use of cost data and suggested solutions and (3) the transferability of experiences to the planned South African implementation of universal health coverage (UHC). Based on our experience and the IDIs, we suggest concrete steps towards the improvement of economic data use in the planning and the establishment of structures mandated under the transition to UHC. Our key recommendations include the following: (1) compile a publicly available and regularly updated in-country cost repository; (2) increase the availability of programmatic outcomes data at the aggregate level; (3) agree upon and implement a set of primary decision criteria for the adoption and funding of interventions; (4) combine the efforts of health economics institutions into a stringent system for health technology assessments and (5) improve the link between national and provincial planning and budgeting.
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The incremental cost of improving immunization coverage in India through the Intensified Mission Indradhanush programme. Health Policy Plan 2021; 36:1316-1324. [PMID: 33950262 PMCID: PMC8428614 DOI: 10.1093/heapol/czab053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/02/2021] [Accepted: 04/21/2021] [Indexed: 11/12/2022] Open
Abstract
Intensified Mission Indradhanush (IMI) was a strategic endeavour launched by the Government of India aiming to achieve 90% full immunization coverage in the country by 2018. The basic strategy of this special drive involved identifying missed children and vaccinating them in temporary outreach sites for 1 week over consecutive 4-month period starting from October 2017. This study estimated the incremental economic and financial cost of conducting IMI in India from a government provider perspective. Five states—Assam, Bihar, Maharashtra, Rajasthan and Uttar Pradesh were purposefully selected because of high concentration of IMI activities. The stratified random sample of 40 districts, 90 sub-districts and 289 sub-centres were included in this study. Cost data were retrospectively collected at all levels from administrative records, financial records and staff interviews involved in IMI. The weighted incremental economic cost per dose (including vaccine costs) was lowest in Uttar Pradesh (US$3.45) and highest in Maharashtra (U$12.23). Incremental economic cost per IMI dose was found to be higher than a recent routine immunization costing study by Chatterjee and colleagues in 2018, suggesting that it requires additional resources to immunize children through an intensified push in hard-to-reach areas. Incremental financial cost of the IMI programme estimated in this study will be helpful for the government for any future planning of such special initiative. The reasons for variation of unit costs of IMI across the study districts are not known, but lower baseline coverage, high population density, migration, geography and terrain and vaccinating small numbers of children per session could account for the range of findings. Further analysis is required to understand the determinants of cost variations of the IMI programme, which may aid in better planning and more efficient use of resources for future intensified efforts.
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Estimating the health impact of vaccination against ten pathogens in 98 low-income and middle-income countries from 2000 to 2030: a modelling study. Lancet 2021; 397:398-408. [PMID: 33516338 PMCID: PMC7846814 DOI: 10.1016/s0140-6736(20)32657-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 07/07/2020] [Accepted: 12/03/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND The past two decades have seen expansion of childhood vaccination programmes in low-income and middle-income countries (LMICs). We quantify the health impact of these programmes by estimating the deaths and disability-adjusted life-years (DALYs) averted by vaccination against ten pathogens in 98 LMICs between 2000 and 2030. METHODS 16 independent research groups provided model-based disease burden estimates under a range of vaccination coverage scenarios for ten pathogens: hepatitis B virus, Haemophilus influenzae type B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, Streptococcus pneumoniae, rotavirus, rubella, and yellow fever. Using standardised demographic data and vaccine coverage, the impact of vaccination programmes was determined by comparing model estimates from a no-vaccination counterfactual scenario with those from a reported and projected vaccination scenario. We present deaths and DALYs averted between 2000 and 2030 by calendar year and by annual birth cohort. FINDINGS We estimate that vaccination of the ten selected pathogens will have averted 69 million (95% credible interval 52-88) deaths between 2000 and 2030, of which 37 million (30-48) were averted between 2000 and 2019. From 2000 to 2019, this represents a 45% (36-58) reduction in deaths compared with the counterfactual scenario of no vaccination. Most of this impact is concentrated in a reduction in mortality among children younger than 5 years (57% reduction [52-66]), most notably from measles. Over the lifetime of birth cohorts born between 2000 and 2030, we predict that 120 million (93-150) deaths will be averted by vaccination, of which 58 million (39-76) are due to measles vaccination and 38 million (25-52) are due to hepatitis B vaccination. We estimate that increases in vaccine coverage and introductions of additional vaccines will result in a 72% (59-81) reduction in lifetime mortality in the 2019 birth cohort. INTERPRETATION Increases in vaccine coverage and the introduction of new vaccines into LMICs have had a major impact in reducing mortality. These public health gains are predicted to increase in coming decades if progress in increasing coverage is sustained. FUNDING Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation.
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Cost-effectiveness of postpartum haemorrhage first response bundle and non-surgical interventions for refractory postpartum haemorrhage in India: an ex-ante modelling study. THE LANCET GLOBAL HEALTH 2020. [DOI: 10.1016/s2214-109x(20)30183-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Transitioning financial responsibility for health programs from external donors to developing countries: Key issues and recommendations for policy and research. J Glob Health 2019; 8:010301. [PMID: 29391944 PMCID: PMC5782833 DOI: 10.7189/jogh.08.010301] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Correction: Improved calibration estimators for the total cost of health programs and application to immunization in Brazil. PLoS One 2019; 14:e0215701. [PMID: 30986248 PMCID: PMC6464206 DOI: 10.1371/journal.pone.0215701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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2000. Rapid, Point-of-care Diagnosis of Tuberculosis with Novel Truenat Assay: Cost-Effectiveness and Budgetary Impact Analysis for India’s Public Sector. Open Forum Infect Dis 2018. [PMCID: PMC6254532 DOI: 10.1093/ofid/ofy210.1656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background Methods Results Conclusion Disclosures
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Health impact of delayed implementation of cervical cancer screening programs in India: A modeling analysis. Int J Cancer 2018; 144:687-696. [PMID: 30132850 PMCID: PMC6519250 DOI: 10.1002/ijc.31823] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 07/27/2018] [Accepted: 08/01/2018] [Indexed: 11/22/2022]
Abstract
India has the highest burden of cervical cancer in the world. To estimate the consequences of delaying implementation of organized cervical cancer screening, we projected the avertable burden of disease under different implementation scenarios of a screening program. We used an individual‐based microsimulation model of human papillomavirus (HPV) infection and cervical cancer calibrated to epidemiologic data from India to project age‐specific cancer incidence and mortality reductions associated with screening (once‐in‐a‐lifetime among women aged 30–34 years) with one‐visit visual inspection with acetic acid (VIA) and one‐ and two‐visit HPV DNA testing. We then applied these reductions to a population model to project the lifetime cervical cancer cases and deaths averted under different implementation scenarios taking place from 2017 to 2026: (1) immediate implementation of screening with currently available screening tests (one‐visit VIA, two‐visit HPV testing); (2) immediate implementation of screening with currently available screening tests, with a switch to point‐of‐care one‐visit HPV testing in 5 years; and (3) 5‐year delayed implementation of screening with current screening tests or point‐of‐care HPV testing. Immediate implementation of two‐visit HPV testing with a switch to one‐visit HPV testing averted 574,100 cases and 382,500 deaths over the lifetimes of 81.4 million 30‐ to 34‐year‐old women screened once between 2017 and 2026. Delayed implementation with a one‐visit HPV test averted 209,300 cases and 139,100 deaths. Delaying implementation of screening programs in high‐burden settings will result in substantial morbidity and mortality among women beyond the age for adolescent HPV vaccination. What's new? Nearly one‐quarter of cervical cancer cases worldwide occur in India. Nonetheless, while the disease can be prevented through screening for precancerous lesions, very few Indian women receive Pap tests. Here, the authors estimated cervical cancer burden in India assuming different screening program implementation scenarios, including immediate implementation with both one‐visit VIA and two‐visit human papillomavirus (HPV) testing and delayed implementation with a one‐visit HPV test. Models showed that immediate implementation of two‐visit HPV testing averted more than double the number of cases and deaths from cervical cancer among 30‐ to 34‐year‐old women compared with delayed implementation with one‐visit HPV testing.
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The investment case for hepatitis B and C in South Africa: adaptation and innovation in policy analysis for disease program scale-up. Health Policy Plan 2018; 33:528-538. [PMID: 29529282 PMCID: PMC5894072 DOI: 10.1093/heapol/czy018] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2018] [Indexed: 12/13/2022] Open
Abstract
Even though WHO has approved global goals for hepatitis elimination, most countries have yet to establish programs for hepatitis B and C, which account for 320 million infections and over a million deaths annually. One reason for this slow response is the paucity of robust, compelling analyses showing that national HBV/HCV programs could have a significant impact on these epidemics and save lives in a cost-effective, affordable manner. In this context, our team used an investment case approach to develop a national hepatitis action plan for South Africa, grounded in a process of intensive engagement of local stakeholders. Costs were estimated for each activity using an ingredients-based, bottom-up costing tool designed by the authors. The health impact and cost-effectiveness of the Action Plan were assessed by simulating its four priority interventions (HBV birth dose vaccination, PMTCT, HBV treatment and HCV treatment) using previously developed models calibrated to South Africa's demographic and epidemic profile. The Action Plan is estimated to require ZAR3.8 billion (US$294 million) over 2017-2021, about 0.5% of projected government health spending. Treatment scale-up over the initial 5-year period would avert 13 000 HBV-related and 7000 HCV-related deaths. If scale up continues beyond 2021 in line with WHO goals, more than 670 000 new infections, 200 000 HBV-related deaths, and 30 000 HCV-related deaths could be averted. The incremental cost-effectiveness of the Action Plan is estimated at $3310 per DALY averted, less than the benchmark of half of per capita GDP. Our analysis suggests that the proposed scale-up can be accommodated within South Africa's fiscal space and represents good use of scarce resources. Discussions are ongoing in South Africa on the allocation of budget to hepatitis. Our work illustrates the value and feasibility of using an investment case approach to assess the costs and relative priority of scaling up HBV/HCV services.
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Quantifying and reducing statistical uncertainty in sample-based health program costing studies in low- and middle-income countries. SAGE Open Med 2018; 6:2050312118765602. [PMID: 29636964 PMCID: PMC5888835 DOI: 10.1177/2050312118765602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 02/26/2018] [Indexed: 11/15/2022] Open
Abstract
Objectives: In many low- and middle-income countries, the costs of delivering public health programs such as for HIV/AIDS, nutrition, and immunization are not routinely tracked. A number of recent studies have sought to estimate program costs on the basis of detailed information collected on a subsample of facilities. While unbiased estimates can be obtained via accurate measurement and appropriate analyses, they are subject to statistical uncertainty. Quantification of this uncertainty, for example, via standard errors and/or 95% confidence intervals, provides important contextual information for decision-makers and for the design of future costing studies. While other forms of uncertainty, such as that due to model misspecification, are considered and can be investigated through sensitivity analyses, statistical uncertainty is often not reported in studies estimating the total program costs. This may be due to a lack of awareness/understanding of (1) the technical details regarding uncertainty estimation and (2) the availability of software with which to calculate uncertainty for estimators resulting from complex surveys. We provide an overview of statistical uncertainty in the context of complex costing surveys, emphasizing the various potential specific sources that contribute to overall uncertainty. Methods: We describe how analysts can compute measures of uncertainty, either via appropriately derived formulae or through resampling techniques such as the bootstrap. We also provide an overview of calibration as a means of using additional auxiliary information that is readily available for the entire program, such as the total number of doses administered, to decrease uncertainty and thereby improve decision-making and the planning of future studies. Results: A recent study of the national program for routine immunization in Honduras shows that uncertainty can be reduced by using information available prior to the study. This method can not only be used when estimating the total cost of delivering established health programs but also to decrease uncertainty when the interest lies in assessing the incremental effect of an intervention. Conclusion: Measures of statistical uncertainty associated with survey-based estimates of program costs, such as standard errors and 95% confidence intervals, provide important contextual information for health policy decision-making and key inputs for the design of future costing studies. Such measures are often not reported, possibly because of technical challenges associated with their calculation and a lack of awareness of appropriate software. Modern statistical analysis methods for survey data, such as calibration, provide a means to exploit additional information that is readily available but was not used in the design of the study to significantly improve the estimation of total cost through the reduction of statistical uncertainty.
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Morocco investment case for hepatitis C: using analysis to drive the translation of political commitment to action. JOURNAL OF GLOBAL HEALTH REPORTS 2018. [DOI: 10.29392/joghr.3.e2019011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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The cost-effectiveness of alternative vaccination strategies for polyvalent meningococcal vaccines in Burkina Faso: A transmission dynamic modeling study. PLoS Med 2018; 15:e1002495. [PMID: 29364884 PMCID: PMC5783340 DOI: 10.1371/journal.pmed.1002495] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 12/19/2017] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND The introduction of a conjugate vaccine for serogroup A Neisseria meningitidis has dramatically reduced disease in the African meningitis belt. In this context, important questions remain about the performance of different vaccine policies that target remaining serogroups. Here, we estimate the health impact and cost associated with several alternative vaccination policies in Burkina Faso. METHODS AND FINDINGS We developed and calibrated a mathematical model of meningococcal transmission to project the disability-adjusted life years (DALYs) averted and costs associated with the current Base policy (serogroup A conjugate vaccination at 9 months, as part of the Expanded Program on Immunization [EPI], plus district-specific reactive vaccination campaigns using polyvalent meningococcal polysaccharide [PMP] vaccine in response to outbreaks) and three alternative policies: (1) Base Prime: novel polyvalent meningococcal conjugate (PMC) vaccine replaces the serogroup A conjugate in EPI and is also used in reactive campaigns; (2) Prevention 1: PMC used in EPI and in a nationwide catch-up campaign for 1-18-year-olds; and (3) Prevention 2: Prevention 1, except the nationwide campaign includes individuals up to 29 years old. Over a 30-year simulation period, Prevention 2 would avert 78% of the meningococcal cases (95% prediction interval: 63%-90%) expected under the Base policy if serogroup A is not replaced by remaining serogroups after elimination, and would avert 87% (77%-93%) of meningococcal cases if complete strain replacement occurs. Compared to the Base policy and at the PMC vaccine price of US$4 per dose, strategies that use PMC vaccine (i.e., Base Prime and Preventions 1 and 2) are expected to be cost saving if strain replacement occurs, and would cost US$51 (-US$236, US$490), US$188 (-US$97, US$626), and US$246 (-US$53, US$703) per DALY averted, respectively, if strain replacement does not occur. An important potential limitation of our study is the simplifying assumption that all circulating meningococcal serogroups can be aggregated into a single group; while this assumption is critical for model tractability, it would compromise the insights derived from our model if the effectiveness of the vaccine differs markedly between serogroups or if there are complex between-serogroup interactions that influence the frequency and magnitude of future meningitis epidemics. CONCLUSIONS Our results suggest that a vaccination strategy that includes a catch-up nationwide immunization campaign in young adults with a PMC vaccine and the addition of this new vaccine into EPI is cost-effective and would avert a substantial portion of meningococcal cases expected under the current World Health Organization-recommended strategy of reactive vaccination. This analysis is limited to Burkina Faso and assumes that polyvalent vaccines offer equal protection against all meningococcal serogroups; further studies are needed to evaluate the robustness of this assumption and applicability for other countries in the meningitis belt.
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The health and economic impact of scaling cervical cancer prevention in 50 low- and lower-middle-income countries. Int J Gynaecol Obstet 2017; 138 Suppl 1:47-56. [DOI: 10.1002/ijgo.12184] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Projected savings through public health voluntary licences of HIV drugs negotiated by the Medicines Patent Pool (MPP). PLoS One 2017; 12:e0177770. [PMID: 28542239 PMCID: PMC5444652 DOI: 10.1371/journal.pone.0177770] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 05/03/2017] [Indexed: 11/19/2022] Open
Abstract
The Medicines Patent Pool (MPP) was established in 2010 to ensure timely access to low-cost generic versions of patented antiretroviral (ARV) medicines in low- and middle-income countries (LMICs) through the negotiation of voluntary licences with patent holders. While robust data on the savings generated by MPP and other major global public health initiatives is important, it is also difficult to quantify. In this study, we estimate the savings generated by licences negotiated by the MPP for ARV medicines to treat HIV/AIDS in LMICs for the period 2010–2028 and generate a cost-benefit ratio–based on people living with HIV (PLHIVs) in any new countries which gain access to an ARV due to MPP licences and the price differential between originator’s tiered price and generics price, within the period where that ARV is patented. We found that the direct savings generated by the MPP are estimated to be USD 2.3 billion (net present value) by 2028, representing an estimated cost-benefit ratio of 1:43, which means for every USD 1 spent on MPP, the global public health community saves USD 43. The saving of USD 2.3 billion is equivalent to more than 24 million PLHIV receiving first-line ART in LMICs for 1 year at average prices today.
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Invasive cardiopulmonary exercise testing in the evaluation of unexplained dyspnea: Insights from a multidisciplinary dyspnea center. Eur J Prev Cardiol 2017; 24:1190-1199. [PMID: 28506086 DOI: 10.1177/2047487317709605] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Unexplained dyspnea is a common diagnosis that often results in repeated diagnostic testing and even delayed treatments while a determination of the cause is being investigated. Through a retrospective study, we evaluated the diagnostic efficacy of a multidisciplinary dyspnea evaluation center (MDEC) using invasive cardiopulmonary exercise test to diagnose potential causes of unexplained dyspnea. Methods We reviewed the medical records of all patients referred with unexplained dyspnea to the MDEC between March 2011 and October 2014. We assessed the diagnostic efficacy before and after presentation to the MDEC. Results During the study period a total of 864 patients were referred to the MDEC and, of those, 530 patients underwent further investigation with invasive cardiopulmonary exercise test and constituted the study sample. The median age was 57 (44-68) years, 67.2% were women, and median body mass index was 26.22 (22.78-31.01). A diagnosis was made in 530 patients including: exercise pulmonary arterial hypertension of 88 (16.6%), heart failure with preserved ejection fraction of 94 (17.7%), dysautonomia 112 (21.1%), oxidative myopathy of 130 (24.5%), primary hyperventilation of 43 (8.1%), and other 58 (10.9%). The time from initial presentation to referral was significantly longer than time to diagnosis after referral for non-standardized conventional methods versus diagnosis through MDEC using invasive cardiopulmonary exercise test (511 days (292-1095 days) vs. 27 days (13-53 days), p < 0.0001). In a subgroup analysis, we reviewed that patients referred from cardiovascular clinics were more likely to have a greater number of diagnostic tests performed and, conversely, patients referred from pulmonary clinics were more likely to have a greater number of treatments prescribed before referral to MDEC. Conclusions As a result of this retrospective study, we have evaluated that a multidisciplinary approach that includes invasive cardiopulmonary exercise test dramatically reduces the time to diagnosis compared with traditional treatment and testing methods.
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Understanding and improving the one and three times GDP per capita cost-effectiveness thresholds. Health Policy Plan 2016; 32:141-145. [DOI: 10.1093/heapol/czw096] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2016] [Indexed: 11/13/2022] Open
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Cost-Effectiveness of a Model Infection Control Program for Preventing Multi-Drug-Resistant Organism Infections in Critically Ill Surgical Patients. Surg Infect (Larchmt) 2016; 17:589-95. [PMID: 27399263 DOI: 10.1089/sur.2015.222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Interventions to contain two multi-drug-resistant Acinetobacter (MDRA) outbreaks reduced the incidence of multi-drug-resistant (MDR) organisms, specifically methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and Clostridium difficile in the general surgery intensive care unit (ICU) of our hospital. We therefore conducted a cost-effective analysis of a proactive model infection-control program to reduce transmission of MDR organisms based on the practices used to control the MDRA outbreak. METHODS We created a model of a proactive infection control program based on the 2011 MDRA outbreak response. We built a decision analysis model and performed univariable and probabilistic sensitivity analyses to evaluate the cost-effectiveness of the proposed program compared with standard infection control practices to reduce transmission of these MDR organisms. RESULTS The cost of a proactive infection control program would be $68,509 per year. The incremental cost-effectiveness ratio (ICER) was calculated to be $3,804 per aversion of transmission of MDR organisms in a one-year period compared with standard infection control. On the basis of probabilistic sensitivity analysis, a willingness-to-pay (WTP) threshold of $14,000 per transmission averted would have a 42% probability of being cost-effective, rising to 100% at $22,000 per transmission averted. CONCLUSIONS This analysis gives an estimated ICER for implementing a proactive program to prevent transmission of MDR organisms in the general surgery ICU. To better understand the causal relations between the critical steps in the program and the rate reductions, a randomized study of a package of interventions to prevent healthcare-associated infections should be considered.
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Abstract
OBJECTIVES To estimate the present value of current and future funding needed for HIV treatment and prevention in 9 sub-Saharan African (SSA) countries that account for 70% of HIV burden in Africa under different scenarios of intervention scale-up. To analyse the gaps between current expenditures and funding obligation, and discuss the policy implications of future financing needs. DESIGN We used the Goals module from Spectrum, and applied the most up-to-date cost and coverage data to provide a range of estimates for future financing obligations. The four different scale-up scenarios vary by treatment initiation threshold and service coverage level. We compared the model projections to current domestic and international financial sources available in selected SSA countries. RESULTS In the 9 SSA countries, the estimated resources required for HIV prevention and treatment in 2015-2050 range from US$98 billion to maintain current coverage levels for treatment and prevention with eligibility for treatment initiation at CD4 count of <500/mm(3) to US$261 billion if treatment were to be extended to all HIV-positive individuals and prevention scaled up. With the addition of new funding obligations for HIV--which arise implicitly through commitment to achieve higher than current treatment coverage levels--overall financial obligations (sum of debt levels and the present value of the stock of future HIV funding obligations) would rise substantially. CONCLUSIONS Investing upfront in scale-up of HIV services to achieve high coverage levels will reduce HIV incidence, prevention and future treatment expenditures by realising long-term preventive effects of ART to reduce HIV transmission. Future obligations are too substantial for most SSA countries to be met from domestic sources alone. New sources of funding, in addition to domestic sources, include innovative financing. Debt sustainability for sustained HIV response is an urgent imperative for affected countries and donors.
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Cost-effectiveness analysis of introducing universal human papillomavirus vaccination of girls aged 11 years into the National Immunization Program in Brazil. Vaccine 2016; 33 Suppl 1:A135-42. [PMID: 25919154 DOI: 10.1016/j.vaccine.2014.12.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 12/12/2014] [Accepted: 12/15/2014] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To evaluate the impact and cost-effectiveness of introducing universal human papillomavirus (HPV) vaccination into the National Immunization Program (NIP) in Brazil. METHODS The Excel-based CERVIVAC decision support model was used to compare two strategies: (1) status quo (with current screening program) and (2) vaccination of a cohort of 11-year-old girls. National parameters for the epidemiology and costs of cervical cancer were estimated in depth. The estimates were based on data from the health information systems of the public health system, the PNAD 2008 national household survey, and relevant scientific literature on Brazil. Costs are expressed in 2008 United States dollars (US$), and a 5% discount rate is applied to both future costs and future health benefits. RESULTS Introducing the HPV vaccine would reduce the burden of disease. The model estimated there would be 229 deaths avoided and 6677 disability-adjusted life years (DALYs) averted in the vaccinated cohort. The incremental cost-effectiveness ratios (ICERs) per DALY averted from the perspectives of the government (US$ 7663), health system (US$ 7412), and society (US$ 7298) would be considered cost-effective, according to the parameters adopted by the World Health Organization. In the sensitivity analysis, the ICERs were most sensitive to variations in discount rate, disease burden, vaccine efficacy, and proportion of cervical cancer caused by types 16 and 18. However, universal HPV vaccination remained a cost-effective strategy in most variations of the key estimates. CONCLUSIONS Vaccine introduction could contribute additional benefits in controlling cervical cancer, but it requires large investments by the NIP. Among the essential conditions for attaining the expected favorable results are immunization program sustainability, equity in a population perspective, improvement of the screening program, and development of a surveillance system.
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ProVac Global Initiative: a vision shaped by ten years of supporting evidence-based policy decisions. Vaccine 2016; 33 Suppl 1:A21-7. [PMID: 25919164 DOI: 10.1016/j.vaccine.2014.12.080] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 12/19/2014] [Accepted: 12/22/2014] [Indexed: 10/23/2022]
Abstract
INTRODUCTION The Pan American Health Organization (PAHO) created the ProVac Initiative in 2004 with the goal of strengthening national technical capacity to make evidence-based decisions on new vaccine introduction, focusing on economic evaluations. In view of the 10th anniversary of the ProVac Initiative, this article describes its progress and reflects on lessons learned to guide the next phase. METHODS We quantified the output of the Initiative's capacity-building efforts and critically assess its progress toward achieving the milestones originally proposed in 2004. Additionally, we reviewed how country studies supported by ProVac have directly informed and strengthened the deliberations around new vaccine introduction. RESULTS Since 2004, ProVac has conducted four regional workshops and supported 24 health economic analyses in 15 Latin American and Caribbean countries. Five Regional Centers of Excellence were funded, resulting in six operational research projects and nine publications. Twenty four decisions on new vaccine introductions were supported with ProVac studies. Enduring products include the TRIVAC and CERVIVAC cost-effectiveness models, the COSTVAC program costing model, methodological guides, workshop training materials and the OLIVES on-line data repository. Ten NITAGs were strengthened through ProVac activities. DISCUSSION The evidence accumulated suggests that initiatives with emphasis on sustainable training and direct support for countries to generate evidence themselves, can help accelerate the introduction of the most valuable new vaccines. International and Regional Networks of Collaborators are necessary to provide technical support and tools to national teams conducting analyses. Timeliness, integration, quality and country ownership of the process are four necessary guiding principles for national economic evaluations to have an impact on policymaking. It would be an asset to have a model that offers different levels of complexity to choose from depending on the vaccine being evaluated, the availability of data, and the time frame of the decision. CONCLUSION Decision support for new vaccine introduction in low- and middle-income countries is critical to maximizing the efficiency and impact of vaccination programs. Global technical cooperation will be required. In the future, PAHO and WHO have an opportunity to expand the reach of the ProVac philosophy, models, and methods to additional regions and countries requiring real-time support. The ProVac Global Initiative is proposed as an effective mechanism to do so.
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The Cost of Responding to an Acinetobacter Outbreak in Critically Ill Surgical Patients. Surg Infect (Larchmt) 2015; 17:58-64. [PMID: 26356287 DOI: 10.1089/sur.2015.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Our institution had an outbreak of multi-drug-resistant Acinetobacter (MDRA) in 2011. We analyzed the costs of responding to this outbreak from the hospital's perspective. METHODS We estimated retrospectively the excess costs associated with an MDRA outbreak response at a major academic medical center, including the costs of staffing, supplies, administrative time, deep cleaning, and environmental testing. Differences in mean costs before and during the 2011 MDRA outbreak were analyzed using the Student t-test. RESULTS The overall excess cost incurred during the outbreak response was $371,079 in 2011 U.S. dollars. The largest contributors were the extra resources needed to staff and clean the two intensive care units (ICUs) (78%). In the general surgery ICU, the mean weekly cost of nursing during the outbreak was $13,276 more for regular hours (+15%; p < 0.01) than in the pre-outbreak period and $2,682 more for overtime hours (+86%; p = 0.02). In the trauma ICU, the cost was $20,746 more for regular hours (+24%; p < 0.01) and $3,445 more for overtime hours (+124%; p < 0.01). The costs of supplies ($13,036; +30%; p = 0.03) and gloves ($2,572; +48%; p = 0.01) also were greater during the outbreak. Administrative time, consumables, use of a surge pod, and environmental testing accounted for the remainder of the extra costs. CONCLUSIONS Our institution incurred $371,079 in excess costs as a result of an MDRA outbreak. This figure does not include the costs related to treatment of the infections, loss of reimbursement because of hospital-acquired infection, legal services, or changes in staff morale, patient satisfaction, or hospital reputation. Strategies to prevent and control such outbreaks better have substantial value.
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Funding AIDS programmes in the era of shared responsibility: an analysis of domestic spending in 12 low-income and middle-income countries. LANCET GLOBAL HEALTH 2015; 3:e52-61. [PMID: 25539970 DOI: 10.1016/s2214-109x(14)70342-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND As the incomes of many AIDS-burdened countries grow and donors' budgets for helping to fight the disease tighten, national governments and external funding partners increasingly face the following question: what is the capacity of countries that are highly affected by AIDS to finance their responses from domestic sources, and how might this affect the level of donor support? In this study, we attempt to answer this question. METHODS We propose metrics to estimate domestic AIDS financing, using methods related to national prioritisation of health spending, disease burden, and economic growth. We apply these metrics to 12 countries in sub-Saharan Africa with a high prevalence of HIV/AIDS, generating scenarios of possible future domestic expenditure. We compare the results with total AIDS financing requirements to calculate the size of the resulting funding gaps and implications for donors. FINDINGS Nearly all 12 countries studied fall short of the proposed expenditure benchmarks. If they met these benchmarks fully, domestic spending on AIDS would increase by 2·5 times, from US$2·1 billion to $5·1 billion annually, covering 64% of estimated future funding requirements and leaving a gap of around a third of the total $7·9 billion needed. Although upper-middle-income countries, such as Botswana, Namibia, and South Africa, would become financially self-reliant, lower-income countries, such as Mozambique and Ethiopia, would remain heavily dependent on donor funds. INTERPRETATION The proposed metrics could be useful to stimulate further analysis and discussion around domestic spending on AIDS and corresponding donor contributions, and to structure financial agreements between recipient country governments and donors. Coupled with improved resource tracking, such metrics could enhance transparency and accountability for efficient use of money and maximise the effect of available funding to prevent HIV infections and save lives. FUNDING US Centers for Disease Control and Prevention.
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Estimating age-based antiretroviral therapy costs for HIV-infected children in resource-limited settings based on World Health Organization weight-based dosing recommendations. BMC Health Serv Res 2014; 14:201. [PMID: 24885453 PMCID: PMC4021070 DOI: 10.1186/1472-6963-14-201] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 04/02/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pediatric antiretroviral therapy (ART) has been shown to substantially reduce morbidity and mortality in HIV-infected infants and children. To accurately project program costs, analysts need accurate estimations of antiretroviral drug (ARV) costs for children. However, the costing of pediatric antiretroviral therapy is complicated by weight-based dosing recommendations which change as children grow. METHODS We developed a step-by-step methodology for estimating the cost of pediatric ARV regimens for children ages 0-13 years old. The costing approach incorporates weight-based dosing recommendations to provide estimated ARV doses throughout childhood development. Published unit drug costs are then used to calculate average monthly drug costs. We compared our derived monthly ARV costs to published estimates to assess the accuracy of our methodology. RESULTS The estimates of monthly ARV costs are provided for six commonly used first-line pediatric ARV regimens, considering three possible care scenarios. The costs derived in our analysis for children were fairly comparable to or slightly higher than available published ARV drug or regimen estimates. CONCLUSIONS The methodology described here can be used to provide an accurate estimation of pediatric ARV regimen costs for cost-effectiveness analysts to project the optimum packages of care for HIV-infected children, as well as for program administrators and budget analysts who wish to assess the feasibility of increasing pediatric ART availability in constrained budget environments.
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Abstracts of the 13th Bethune Round Table Conference on International Surgery. May 10-11, 2013. Vancouver, British Columbia, Canada. Can J Surg 2013; 56:S44-52. [PMID: 23883512 DOI: 10.1503/cjs.015713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Establishing a regional network of academic centers to support decision making for new vaccine introduction in Latin America and the Caribbean: The ProVac experience. Vaccine 2013; 31 Suppl 3:C12-8. [DOI: 10.1016/j.vaccine.2013.05.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 04/30/2013] [Accepted: 05/08/2013] [Indexed: 11/29/2022]
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Cost-effectiveness of additional catheter-directed thrombolysis for deep vein thrombosis. J Thromb Haemost 2013; 11:1032-42. [PMID: 23452204 PMCID: PMC4027959 DOI: 10.1111/jth.12184] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 02/20/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Additional treatment with catheter-directed thrombolysis (CDT) has recently been shown to reduce post-thrombotic syndrome (PTS). OBJECTIVES To estimate the cost effectiveness of additional CDT compared with standard treatment alone. METHODS Using a Markov decision model, we compared the two treatment strategies in patients with a high proximal deep vein thrombosis (DVT) and a low risk of bleeding. The model captured the development of PTS, recurrent venous thromboembolism and treatment-related adverse events within a lifetime horizon and the perspective of a third-party payer. Uncertainty was assessed with one-way and probabilistic sensitivity analyzes. Model inputs from the CaVenT study included PTS development, major bleeding from CDT and utilities for post DVT states including PTS. The remaining clinical inputs were obtained from the literature. Costs obtained from the CaVenT study, hospital accounts and the literature are expressed in US dollars ($); effects in quality adjusted life years (QALY). RESULTS In base case analyzes, additional CDT accumulated 32.31 QALYs compared with 31.68 QALYs after standard treatment alone. Direct medical costs were $64,709 for additional CDT and $51,866 for standard treatment. The incremental cost-effectiveness ratio (ICER) was $20,429/QALY gained. One-way sensitivity analysis showed model sensitivity to the clinical efficacy of both strategies, but the ICER remained < $55,000/QALY over the full range of all parameters. The probability that CDT is cost effective was 82% at a willingness to pay threshold of $50,000/QALY gained. CONCLUSIONS Additional CDT is likely to be a cost-effective alternative to the standard treatment for patients with a high proximal DVT and a low risk of bleeding.
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Abstract
OBJECTIVE To compare the cost-effectiveness of hepatitis B virus (HBV) control strategies combining universal vaccination with hepatitis B immunoglobulin (HBIG) treatment for neonates of carrier mothers. METHODS Drawing on Taiwan's experience, we developed a decision-analytic model to estimate the clinical and economic outcomes for 4 strategies: (1) strategy V-universal vaccination; (2) strategy S-V plus screening for hepatitis B surface antigen (HBsAg) and HBIG treatment for HBsAg-positive mothers' neonates; (3) strategy E-V plus screening for hepatitis B e-antigen (HBeAg), HBIG for HBeAg-positive mothers' neonates; (4) strategy S&E-V plus screening for HBsAg then HBeAg, HBIG for all HBeAg-positive, and some HBeAg-negative/HBsAg-positive mothers' neonates. RESULTS Strategy S averted the most infections, followed by S&E, E, and V. In most cases, the more effective strategies were also more costly. The willingness-to-pay (WTP) above which strategy S was cost-effective rose as carrier rate declined and was <$4000 per infection averted for carrier rates >5%. The WTP below which strategy V was optimal also increased as carrier rate declined, from $1400 at 30% carrier rate to $3100 at 5% carrier rate. Strategies involving E were optimal for an intermediate range of WTP that narrowed as carrier rate declined. CONCLUSIONS HBIG treatment for neonates of HBsAg carrier mothers is likely to be a cost-effective addition to universal vaccination, particularly in settings with adequate health care infrastructure. Targeting HBIG to neonates of higher risk HBeAg-positive mothers may be preferred where WTP is moderate. However, in very resource-limited settings, universal vaccination alone is optimal.
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Economic analyses to support decisions about HPV vaccination in low- and middle-income countries: a consensus report and guide for analysts. BMC Med 2013; 11:23. [PMID: 23363734 PMCID: PMC3582485 DOI: 10.1186/1741-7015-11-23] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 01/30/2013] [Indexed: 11/10/2022] Open
Abstract
Low- and middle-income countries need to consider economic issues such as cost-effectiveness, affordability and sustainability before introducing a program for human papillomavirus (HPV) vaccination. However, many such countries lack the technical capacity and data to conduct their own analyses. Analysts informing policy decisions should address the following questions: 1) Is an economic analysis needed? 2) Should analyses address costs, epidemiological outcomes, or both? 3) If costs are considered, what sort of analysis is needed? 4) If outcomes are considered, what sort of model should be used? 5) How complex should the analysis be? 6) How should uncertainty be captured? 7) How should model results be communicated? Selecting the appropriate analysis is essential to ensure that all the important features of the decision problem are correctly represented, but that the analyses are not more complex than necessary. This report describes the consensus of an expert group convened by the World Health Organization, prioritizing key issues to be addressed when considering economic analyses to support HPV vaccine introduction in these countries.
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Performing Country-led Economic Evaluations to Inform Immunization Policy: ProVac Experiences in Latin America and the Caribbean. Value Health Reg Issues 2012; 1:248-253. [DOI: 10.1016/j.vhri.2012.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Economic returns to investment in AIDS treatment in low and middle income countries. PLoS One 2011; 6:e25310. [PMID: 21998648 PMCID: PMC3187775 DOI: 10.1371/journal.pone.0025310] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 08/31/2011] [Indexed: 12/01/2022] Open
Abstract
Since the early 2000s, aid organizations and developing country governments have invested heavily in AIDS treatment. By 2010, more than five million people began receiving antiretroviral therapy (ART)--yet each year, 2.7 million people are becoming newly infected and another two million are dying without ever having received treatment. As the need for treatment grows without commensurate increase in the amount of available resources, it is critical to assess the health and economic gains being realized from increasingly large investments in ART. This study estimates total program costs and compares them with selected economic benefits of ART, for the current cohort of patients whose treatment is cofinanced by the Global Fund to Fight AIDS, Tuberculosis and Malaria. At end 2011, 3.5 million patients in low and middle income countries will be receiving ART through treatment programs cofinanced by the Global Fund. Using 2009 ART prices and program costs, we estimate that the discounted resource needs required for maintaining this cohort are $14.2 billion for the period 2011-2020. This investment is expected to save 18.5 million life-years and return $12 to $34 billion through increased labor productivity, averted orphan care, and deferred medical treatment for opportunistic infections and end-of-life care. Under alternative assumptions regarding the labor productivity effects of HIV infection, AIDS disease, and ART, the monetary benefits range from 81 percent to 287 percent of program costs over the same period. These results suggest that, in addition to the large health gains generated, the economic benefits of treatment will substantially offset, and likely exceed, program costs within 10 years of investment.
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Strengthening the technical capacity at country-level to make informed policy decisions on new vaccine introduction: lessons learned by PAHO's ProVac Initiative. Vaccine 2010; 29:1099-106. [PMID: 21144916 DOI: 10.1016/j.vaccine.2010.11.075] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 11/17/2010] [Accepted: 11/21/2010] [Indexed: 11/26/2022]
Abstract
Rotavirus, pneumococcal conjugate and HPV vaccines have the potential to make substantial gains in health, specifically in reducing child mortality and improving women's health. Decisions regarding new vaccine introduction should be grounded in a broad evidence base that reflects national conditions. In this paper, we describe the Pan American Health Organization ProVac Initiative's experience in strengthening national decision making regarding new vaccine introduction through five sets of activities: (1) strengthening infrastructure for decision making; (2) developing tools for economic analyses and providing training to national multidisciplinary teams; (3) collecting data, conducting analysis, and gathering a framework of evidence; (4) advocating for evidence-based decisions; and (5) effectively planning for new vaccine introduction when evidence supports it. Key lessons learned regarding the role of multidisciplinary country teams, provision of direct technical support, development of tools, and provision of distance and in-person training are highlighted.
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Abstract
INTRODUCTION Physician decisions drive most of the increases in health care expenditures, yet virtually no published literature has sought to understand the types of evidence used by physicians as they make decisions in real time. METHODS Ten pediatric cardiologists recorded every clinically significant decision made during procedures, test interpretation, or delivery of inpatient and outpatient care during 5 full days and 5 half days of care delivery. The basis for each decision was assigned to one of 10 predetermined categories, ranging from arbitrary and anecdotal, to various qualities of published studies, to parental preference and avoiding a lawsuit. RESULTS During the 7.5 days, 1188 decisions (158/day) were made. Almost 80% of decisions were deemed by the physicians to have no basis in any prior published data and fewer than 3% of decisions were based on a study specific to the question at hand. CONCLUSIONS In this pilot study, physicians were unable to cite a formal evidence source for most of their real-time clinical decision making, including those that consumed medical resources. Novel approaches to building an evidence base produced from real-time clinical decisions may be essential for health care reform based on data.
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Adopting a surgical safety checklist could save money and improve the quality of care in U.S. hospitals. Health Aff (Millwood) 2010; 29:1593-9. [PMID: 20820013 PMCID: PMC3069616 DOI: 10.1377/hlthaff.2009.0709] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Use of the World Health Organization's Surgical Safety Checklist has been associated with a significant reduction in major postoperative complications after inpatient surgery. We hypothesized that implementing the checklist in the United States would generate cost savings for hospitals. We performed a decision analysis comparing implementation of the checklist to existing practice in U.S. hospitals. In a hospital with a baseline major complication rate after surgery of at least 3 percent, the checklist generates cost savings once it prevents at least five major complications. Using the checklist would both save money and improve the quality of care in hospitals throughout the United States.
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Abstract
BACKGROUND Development of new, effective, and affordable tuberculosis (TB) therapies has been identified as a critical priority for global TB control. As new candidates emerge from the global TB drug pipeline, the potential impacts of novel, shorter regimens on TB incidence and mortality have not yet been examined. METHODS AND FINDINGS We used a mathematical model of TB to evaluate the expected benefits of shortening the duration of effective chemotherapy for active pulmonary TB. First, we considered general relationships between treatment duration and TB dynamics. Next, as a specific example, we calibrated the model to reflect the current situation in the South-East Asia region. We found that even with continued and rapid progress in scaling up the World Health Organization's DOTS strategy of directly observed, short-course chemotherapy, the benefits of reducing treatment duration would be substantial. Compared to a baseline of continuing DOTS coverage at current levels, and with currently available tools, a 2-mo regimen introduced by 2012 could prevent around 20% (range 13%-28%) of new cases and 25% (range 19%-29%) of TB deaths in South-East Asia between 2012 and 2030. If effective treatment with existing drugs expands rapidly, overall incremental benefits of shorter regimens would be lower, but would remain considerable (13% [range 8%-19%] and 19% [range 15%-23%] reductions in incidence and mortality, respectively, between 2012 and 2030). A ten-year delay in the introduction of new drugs would erase nearly three-fourths of the total expected benefits in this region through 2030. CONCLUSIONS The introduction of new, shorter treatment regimens could dramatically accelerate the reductions in TB incidence and mortality that are expected under current regimens-with up to 2- or 3-fold increases in rates of decline if shorter regimens are accompanied by enhanced case detection. Continued progress in reducing the global TB burden will require a balanced approach to pursuing new technologies while promoting wider implementation of proven strategies.
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Abstract
Antiretroviral therapy (ART) initiated on a prenatal basis in HIV-infected pregnant women is a highly effective method for preventing mother-to-child HIV transmission. We developed a decision analytic model to project the clinical and economic outcomes of alternative HIV screening strategies (voluntary prenatal screening [VPS], routine prenatal screening [RPS], and mandatory newborn screening [MNS]) for a high-risk population of incarcerated pregnant women. Data for the decision model came from the HIV voluntary counseling and testing program at Connecticut's sole correctional facility for women and a comprehensive anonymously linked serosurvey of all inmates who entered the facility during the 2-year period beginning in October 1994. Based on serosurvey results, in the absence of any HIV screening program, 2.5 cases of pediatric HIV infection would be expected per 1000 pregnancies. Multiplied by the discounted lifetime cost per case of $247,000, this translates to a cost of $624 per testing-eligible prison entrant. Entrants were considered eligible if they were pregnant and their HIV status was unknown. MNS would save money, cost $364 per eligible entrant, and simultaneously reduce the rate of infections to 1.1 per 1000 pregnancies. Doing both MNS and RPS is most effective in reducing the rate of new infections (down to 0.2 per 1000 pregnancies). It would, however, increase costs to $430 per eligible entrant. This would result in an incremental cost of $73,603 per additional pediatric HIV case averted when compared with MNS alone. If mandatory newborn testing was not considered a feasible option, RPS would dominate VPS and would be cost-saving compared with no screening. RPS compares favorably with alternative uses of HIV prevention and treatment resources. In correctional facilities where voluntary newborn screening is already in place, our findings show that there remains a small marginal benefit to be realized from switching to RPS. In settings where HIV screening policies are not in place, however, the implementation of RPS can be expected to significantly reduce pediatric HIV cases and net health care expenditures.
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Escherichia coli ghost production by expression of lysis gene E and Staphylococcal nuclease. Appl Environ Microbiol 2004; 69:6106-13. [PMID: 14532068 PMCID: PMC201253 DOI: 10.1128/aem.69.10.6106-6113.2003] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The production of bacterial ghosts from Escherichia coli is accomplished by the controlled expression of phage phiX174 lysis gene E and, in contrast to other gram-negative bacterial species, is accompanied by the rare detection of nonlysed, reproductive cells within the ghost preparation. To overcome this problem, the expression of a secondary killing gene was suggested to give rise to the complete genetic inactivation of the bacterial samples. The expression of staphylococcal nuclease A in E. coli resulted in intracellular accumulation of the protein and degradation of the host DNA into fragments shorter than 100 bp. Two expression systems for the nuclease are presented and were combined with the protein E-mediated lysis system. Under optimized conditions for the coexpression of gene E and the staphylococcal nuclease, the concentration of viable cells fell below the lower limit of detection, whereas the rates of ghost formation were not affected. With regard to the absence of reproductive cells from the ghost fractions, the reduction of viability could be determined as being at least 7 to 8 orders of magnitude. The lysis process was characterized by electrophoretic analysis and absolute quantification of the genetic material within the cells and the culture supernatant via real-time PCR. The ongoing degradation of the bacterial nucleic acids resulted in a continuous quantitative clearance of the genetic material associated with the lysing cells until the concentrations fell below the detection limits of either assay. No functional, released genetic units (genes) were detected within the supernatant during the lysis process, including nuclease expression.
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Abstract
Pasteurella haemolytica is a cattle pathogen of significant economic impact. An effective vaccine against bovine pneumonic pasteurellosis is therefore of high importance. Apart from economic concerns, pasteurellosis caused by P. haemolytica is a serious disease leading to death in cattle if it remains untreated. In this study P. haemolytica-ghosts are presented as a promising vaccine candidate in cattle. To obtain sufficient vaccination material a fermentation protocol for P. haemolytica-ghost production was established. With the obtained experimental P. haemolytica-ghost vaccine, cattle immunization studies were performed based on a Pasteurella cattle challenge model developed specifically for vaccine validation. It was shown that protective immunization of cattle against homologous challenge was induced by adjuvanted P. haemolytica-ghosts. The level of protection was similar to a commercially available vaccine.
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Decreased glomerular expression of agrin in diabetic nephropathy and podocytes, cultured in high glucose medium. EXPERIMENTAL NEPHROLOGY 2001; 9:214-22. [PMID: 11340306 DOI: 10.1159/000052614] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
AIM A decrease in glomerular heparan sulfate (HS) proteoglycan (PG), without apparent decrease in HSPG core protein expression, has been reported to occur in diabetic nephropathy (DN). In most studies however, agrin, the major HSPG core protein in the glomerular basement membrane, has not been studied. This prompted us to study the glomerular expression of agrin in parallel to the expression of HS-glycosaminoglycans (GAG) in biopsies of patients with DN. Furthermore, the influence of glucose on agrin production in cultured podocytes and the expression of agrin in fetal kidneys was investigated. METHODS Cryostat sections of renal biopsies from patients with DN (n = 8) and healthy controls (HC, n = 8), were stained for agrin and HS-GAG. Sections of fetal kidneys were double stained for agrin and CD35 or CD31. Stainings were performed by indirect immunofluorescence (IIF). The production of agrin by cultured human podocytes was tested by ELISA and IIF. RESULTS The expression of agrin, detected by AS46, was significantly reduced in biopsies from patients with DN compared to HC (p < 0.01). Similar findings were observed when monoclonal antibody JM72 was used (p < 0.05). In addition, a significant reduction in the glomerular expression of HS-GAG was detected with JM403 in these patients (p < 0.01). Agrin is expressed in cultured podocytes, the expression hereof was reduced when the cells were cultured in the presence of 25 mM D-glucose (p < 0.01). In biopsies of human fetal kidneys, glomerular expression of agrin coincided with the expression of CD31. In early stages of glomerular differentiation there was a strong staining for agrin and CD31 while CD35 was only slightly positive. CONCLUSIONS Our data argue against a selective dysregulation in HSPG sulfation in DN, but suggest a pivotal role for hyperglycemia in the downregulation of agrin core protein production.
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Comparative studies in the promoter and exon 1 regions of tumour suppressor p53 in several mammalian species: absence of mutations in a panel of spontaneous domestic animal tumours. JOURNAL OF VETERINARY MEDICINE. A, PHYSIOLOGY, PATHOLOGY, CLINICAL MEDICINE 2000; 47:593-7. [PMID: 11199207 DOI: 10.1046/j.1439-0442.2000.00322.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tumour suppressor p53 is critical in a broad panel of tumour types in human, mouse and other mammals. Regions of the promoter and exon 1 play an important role in expression of p53. In the present study, the DNA sequences of promoter and exon 1 regions of four domestic animal species (dog, cat, horse and cattle) are determined and compared with experimental rodents (mouse, rat and hamster) and man. A broad panel of tumour types have been investigated for mutations in this regulatory area in 90 canine, 136 feline, 25 equine and 10 bovine patients. No mutation was detected in any of the tumours analysed.
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Results of flexor-to-extensor and extensor brevis tendon transfer for correction of the crossover second toe deformity. Foot Ankle Int 1999; 20:781-8. [PMID: 10609706 DOI: 10.1177/107110079902001205] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Between 1990 and 1995, 38 patients (42 feet) underwent repair for crossover toe deformity, 31 (35 feet) of whom returned for final examination at an average of 51.6 months (range, 24-81 months). Causes included trauma, iatrogenic, and unknown. Presenting complaints included dorsal pain with either metatarsalgia or joint pain, isolated metatarsophalangeal (MP) joint pain, metatarsalgia, painful plantar callus, metatarsalgia and joint pain, and painful dorsal callus. All patients were treated with one of two operative techniques, either the flexor-to-extensor tendon transfer or the extensor brevis tendon transfer. Choice of procedure depended on the stage of preoperative deformity. Twenty-four patients were completely satisfied with the surgical correction, 6 were satisfied with reservations, and 1 was dissatisfied. The average postoperative AOFAS score for all patients was 85 points (range, 54-100 points), which correlated strongly with patient satisfaction. Twenty-two patients stated that they had no postoperative pain, 8 reported some pain, and 1 had frequent pain at the corrected toe. In 30 feet, there was no recurrence; three patients had mild residual crossover toe deformity, and two patients had recurrent deformity, although all MP joints were stable. Follow-up radiographs demonstrated substantial reduction in MP joint angles in both the AP (from 7 degrees to -1 degree) and lateral (from 45 degrees to 25 degrees) projections. This article reviews the surgical technique of both procedures, proposes specific indications for each, and presents outcomes. Based on our findings, the extensor brevis tendon transfer is appropriate for stage 1, stage 2, and flexible stage 3 deformities. Flexor-to-extensor tendon transfer is appropriate for rigid stage 3 and stage 4 deformities and for all patients with a symptomatic neuroma of the second web space (where the extensor brevis transfer is not possible). Stiffness of the MP joint is a potential problem with the flexor-to-extensor tendon transfer.
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Abstract
Controlled expression of cloned PhiX174 gene E in Gram-negative bacteria results in lysis of the bacteria by formation of an E-specific transmembrane tunnel structure built through the cell envelope complex. Bacterial ghosts from a variety of bacteria are used as non-living candidate vaccines. In the recombinant ghost system, foreign proteins are attached on the inside of the inner membrane as fusions with specific anchor sequences. Ghosts have a sealed periplasmic space and the export of proteins into this space vastly extends the capacity of ghosts or recombinant ghosts to function as carriers of foreign antigens. In addition, S-layer proteins forming shell-like self assembly structures can be expressed in candidate vaccine strains prior to E-mediated lysis. Such recombinant S-layer proteins carrying foreign epitopes further extend the possibilities of ghosts as carriers of foreign epitopes. As ghosts have inherent adjuvant properties, they can be used as adjuvants in combination with subunit vaccines. Subunits or other ligands can also be coupled to matrixes like dextran which are used to fill the internal lumen of ghosts. Oral, aerogenic or parenteral immunization of experimental animals with recombinant ghosts induced specific humoral and cellular immune responses against bacterial and target components including protective mucosal immunity. The most relevant advantage of recombinant bacterial ghosts as immunogens is that no inactivation procedures that denature relevant immunogenic determinants are employed in this production. This fact explains the superior quality of ghosts when compared to other inactivated vaccines. The endotoxic component of the outer membrane does not limit the use of ghosts as vaccine candidates but triggers the release of several potent immunoregulatory cytokines. As carriers, there is no limitation in the size of foreign antigens that can be inserted in the membrane and the capacity of all spaces including the membranes, peri-plasma and internal lumen of the ghosts can be fully utilized. This extended recombinant ghost system represents a new strategy for adjuvant free combination vaccines.
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Abstract
Controlled expression of cloned PhiX174 gene E in Gram-negative bacteria results in lysis of the bacteria by formation of an E-specific transmembrane tunnel structure built through the cell envelope complex. Bacterial ghosts have been produced from a great variety of bacteria and are used as non-living candidate vaccines. In the recombinant ghost system, foreign proteins are attached on the inside of the inner membrane as fusions with specific anchor sequences. Ghosts have a sealed periplasmic space and the export of proteins into this space vastly extents the capacity of ghosts or recombinant ghosts to function as carriers of foreign antigens, immunomodulators or other substances. In addition, S-layer proteins forming shell-like self assembly structures can be expressed in bacterial candidate vaccine strains prior to E-mediated lysis. Such recombinant S-layer proteins carrying inserts of foreign epitopes of up to 600 amino acids within the flexible surface loop areas of the S-layer further extend the possibilities of ghosts as carriers of foreign epitopes. As ghosts do not need the addition of adjuvants to induce immunity in experimental animals they can also be used as carriers or targeting vehicles or as adjuvants in combination with subunit vaccines. Matrixes like dextran which can be used to fill the internal lumen of ghosts can be substituted with various ligands to bind the subunit or other materials of interest. Oral, aerogenic or parenteral immunization of experimental animals with recombinant ghosts induced specific humoral and cellular immune responses against bacterial and target components including protective mucosal immunity. The most relevant advantage of ghosts and recombinant bacterial ghosts as immunogens is that no inactivation procedures that denature relevant immunogenic determinants are employed in the production of ghosts. This fact explains the superior quality of ghosts when compared to other inactivated vaccines. As carriers of foreign antigens there is no limitation in the size of foreign antigens to be inserted and the capacity of all spaces including the membranes, periplasma and internal lumen of the ghosts can be fully utilized. Using the different building blocks and combining them into the recombinant ghost system represents a new strategy for adjuvant free combination vaccines.
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Heterologous phi X174 gene E-expression in Ralstonia eutropha: E-mediated lysis is not restricted to gamma-subclass of proteobacteria. J Biotechnol 1998; 66:211-7. [PMID: 9866870 DOI: 10.1016/s0168-1656(98)00128-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
E-lysis of Ralstonia eutropha H16, which belongs to the beta-subclass, was undertaken to verify whether transmembrane tunnel formation is possible in bacteria which do not belong to the enterobacteriaceae. For this purpose, a new gene E expression plasmid, pKG12, with two origins of replication, oriV and oriT, from plasmid pRP4, chloramphenicol and kanamycin resistance genes and a casette composed of lambda cI857 and lambda pR gene E was constructed. Temperature upshift of R. eutropha H16 (pKG12) from 28 to 45 degrees C during exponential growth resulted in lysis of the strain with features characteristic of E-mediated lysis of Escherichia coli. The cytoplasmic contents released can easily be separated from the still intact envelope fraction by centrifugation or filtration. As R. eutropha H16 represents an important industrial organism, E-mediated lysis could facilitate procedures for the recovery of intracellular mediators or products like polyhydroxyalkanoates.
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Abstract
The poly(beta-hydroxybutyrate) (PHB) biosynthetic genes of Ralstonia eutropha that are organized in a single operon (phaCAB) have been cloned in Escherichia coli, where the expression of the genes in the wild-type pha operon from plasmid pTZ18U-PHB leads to the formation of 50-80% PHB/celldry mass when the cells are grown in Luria-Bertani medium supplemented with 1% glucose (w/v). In combination with the phaCAB genes, expression of cloned lysis gene E of bacteriophage PhiX174 from plasmid pSH2 has been used to release PHB granules produced in E. coli. It was shown that small PHB granules in a semiliquid stage are squeezed out of the cells through the E-lysis tunnel structure which is characterized by a small opening in the envelope with borders of fused inner and outer membranes. All envelope components remain intact after E-lysis and can be removed from the mixture of released PHB granules by density gradient centrifugation. In addition, a modified E-lysis procedure is described which enables the release of PHB from cell pellets in pure water or low ionic strength buffer. PHB granules in aqueous solution can be aggregated by divalent cations. Addition of glassmilk speeds up the agglomeration of PHB granules and binding to glass beads can either be used for collection or further purification of PHB in aqueous solutions.
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