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Nagi MA, Luangsinsiri C, Thavorncharoensap M. A systematic review of economic evaluations of vaccines in Middle East and North Africa countries: is existing evidence good enough to support policy decision-making? Expert Rev Pharmacoecon Outcomes Res 2021; 21:1159-1178. [PMID: 34252335 DOI: 10.1080/14737167.2021.1954508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION A vaccine introduction process should be systematic and transparent and take into account many factors, including cost-effectiveness evidence. This study aimed to assess quantity, characteristic, and quality of economic evaluation (EE) studies on vaccines performed in Middle East and North Africa (MENA) countries. AREAS COVERED PubMed and Scopus electronic databases were searched since inception to December 2019 to identify published EE studies of vaccines, which were conducted in the 26 MENA countries. Methodological quality of the included studies was evaluated using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. EXPERT OPINION Of the 616 studies identified, 46 were included in the review. Most studies (65%) were conducted in Iran, Israel, and Turkey. The most commonly evaluated vaccines were rotavirus vaccine (n = 15; 33%), human Papillomavirus vaccine (n = 8; 17%), and pneumococcal vaccine (n = 7; 15%). We classified 5 (11%), 27 (59%), 12 (26%), and 2 (4%) studies as excellent, good, moderate, and poor quality, respectively. There were limited cost-effectiveness evidences in the region. It is imperative to have local guidelines on good practice and reporting, availability of local data, and funding sources to improve quantity and quality of EE studies of vaccines in the region, thereby, facilitating transparent and consistent decision-making processes.
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Affiliation(s)
- Mouaddh Abdulmalik Nagi
- Doctor of Philosophy Program in Social, Economic, and Administrative Pharmacy, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.,Faculty of Medical Sciences, Aljanad University for Science and Technology, Taiz, Yemen
| | - Chaisiri Luangsinsiri
- Doctor of Philosophy Program in Social, Economic, and Administrative Pharmacy, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.,Department of Clinical Pharmacy, Faculty of Pharmacy, Srinakharinwirot University, Nakhon Nayok, Thailand
| | - Montarat Thavorncharoensap
- Social and Administrative Pharmacy Excellence Research (SAPER) Unit, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Rajathevi, Bangkok, Thailand
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Yemeke TT, Mitgang E, Wedlock PT, Higgins C, Chen HH, Pallas SW, Abimbola T, Wallace A, Bartsch SM, Lee BY, Ozawa S. Promoting, seeking, and reaching vaccination services: A systematic review of costs to immunization programs, beneficiaries, and caregivers. Vaccine 2021; 39:4437-4449. [PMID: 34218959 PMCID: PMC10711749 DOI: 10.1016/j.vaccine.2021.05.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Understanding the costs to increase vaccination demand among under-vaccinated populations, as well as costs incurred by beneficiaries and caregivers for reaching vaccination sites, is essential to improving vaccination coverage. However, there have not been systematic analyses documenting such costs for beneficiaries and caregivers seeking vaccination. METHODS We searched PubMed, Scopus, and the Immunization Delivery Cost Catalogue (IDCC) in 2019 for the costs for beneficiaries and caregivers to 1) seek and know how to access vaccination (i.e., costs to immunization programs for social mobilization and interventions to increase vaccination demand), 2) take time off from work, chores, or school for vaccination (i.e., productivity costs), and 3) travel to vaccination sites. We assessed if these costs were specific to populations that faced other non-cost barriers, based on a framework for defining hard-to-reach and hard-to-vaccinate populations for vaccination. RESULTS We found 57 studies describing information, education, and communication (IEC) costs, social mobilization costs, and the costs of interventions to increase vaccination demand, with mean costs per dose at $0.41 (standard deviation (SD) $0.83), $18.86 (SD $50.65) and $28.23 (SD $76.09) in low-, middle-, and high-income countries, respectively. Five studies described productivity losses incurred by beneficiaries and caregivers seeking vaccination ($38.33 per person; SD $14.72; n = 3). We identified six studies on travel costs incurred by beneficiaries and caregivers attending vaccination sites ($11.25 per person; SD $9.54; n = 4). Two studies reported social mobilization costs per dose specific to hard-to-reach populations, which were 2-3.5 times higher than costs for the general population. Eight studies described barriers to vaccination among hard-to-reach populations. CONCLUSION Social mobilization/IEC costs are well-characterized, but evidence is limited on costs incurred by beneficiaries and caregivers getting to vaccination sites. Understanding the potential incremental costs for populations facing barriers to reach vaccination sites is essential to improving vaccine program financing and planning.
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Affiliation(s)
- Tatenda T Yemeke
- Division of Practice Advancement and Clinical Education, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Elizabeth Mitgang
- Public Health Informatics, Computational, and Operations Research (PHICOR), CUNY Graduate School of Public Health and Health Policy, New York City, NY 10027, USA
| | - Patrick T Wedlock
- Public Health Informatics, Computational, and Operations Research (PHICOR), CUNY Graduate School of Public Health and Health Policy, New York City, NY 10027, USA
| | - Colleen Higgins
- Division of Practice Advancement and Clinical Education, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Hui-Han Chen
- Division of Practice Advancement and Clinical Education, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Sarah W Pallas
- Global Immunization Division, U.S. Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Taiwo Abimbola
- Global Immunization Division, U.S. Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Aaron Wallace
- Global Immunization Division, U.S. Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Sarah M Bartsch
- Public Health Informatics, Computational, and Operations Research (PHICOR), CUNY Graduate School of Public Health and Health Policy, New York City, NY 10027, USA
| | - Bruce Y Lee
- Public Health Informatics, Computational, and Operations Research (PHICOR), CUNY Graduate School of Public Health and Health Policy, New York City, NY 10027, USA
| | - Sachiko Ozawa
- Division of Practice Advancement and Clinical Education, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA; Department of Maternal and Child Health, UNC Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA.
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Ghildayal N. Cost-effectiveness of Hepatitis A vaccination in a developed and developing country. Int J Health Care Qual Assur 2020; 32:1175-1199. [PMID: 31566514 DOI: 10.1108/ijhcqa-05-2019-0096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE Hepatitis A is a prevalent disease that is largely preventable by vaccine usage. The vaccine for this illness is highly underused in most regions. In an attempt to find the strategies that are most beneficial in regard to quality-adjusted life years (QALYs) and cost in current environments, the purpose of this paper is to conduct cost-effectiveness analyses to investigate vaccination strategies in a more economically developed country (MEDC), generally known as a "developed" area: the USA, and a less economically developed country (LEDC), generally known as a "developing" area: the state of Rio de Janeiro, Brazil. DESIGN/METHODOLOGY/APPROACH This study used a dynamic transmission model for comparative effectiveness analyses. The model ran two different scenarios. The two regions studied have different policies and strategies for Hepatitis A vaccination currently, and also used different strategies in 2009. In the USA, a universal vaccination policy was modeled, along with a scenario in which it was removed. In Rio de Janeiro, a no vaccination policy was modeled, along with a scenario in which a universal vaccination policy was effected. FINDINGS The comparison of resulting incremental cost-effectiveness ratio values to accepted threshold values showed universal vaccination to be cost-effective in both the USA and Rio de Janeiro as compared to no vaccination. When episode and vaccination costs and vaccination efficacy were varied, this still remained true. Universal vaccination was found to result in lower incidence of Hepatitis A in both the USA and Rio de Janeiro. Over the twenty-year time horizon, universal vaccination is projected to prevent 506,945 cases of symptomatic Hepatitis A in the USA and 42,318 cases of Hepatitis A in Rio de Janeiro. Other benefits include a projected increase in cumulative QALYs through the use of universal vaccination. ORIGINALITY/VALUE This analysis showed universal vaccination to be cost-effective as compared to no vaccination, and portions of the study's approach had not previously been applied in tandem to investigate Hepatitis A interventions. The results may help foster higher compliance rates for Hepatitis A vaccination and even greater per-person economic benefits of universal vaccination, particularly in the USA. The purpose of this study is also to encourage elevated levels of surveillance on age of infection in developing regions and consistent reevaluation utilizing dynamic transmission models in both the USA and Brazil, as well as other rapidly developing regions, in order to prevent future epidemics and costs associated with the disease.
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Affiliation(s)
- Nidhi Ghildayal
- University of Minnesota Twin Cities , Minneapolis, Minnesota, USA
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Levine H, Kopel E, Anis E, Givon-Lavi N, Dagan R. The impact of a national routine immunisation programme initiated in 1999 on Hepatitis A incidence in Israel, 1993 to 2012. ACTA ACUST UNITED AC 2015; 20:3-10. [PMID: 25719962 DOI: 10.2807/1560-7917.es2015.20.7.21040] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Data on long-term impact of universal national vaccination programmes against hepatitis A are lacking. We aimed at evaluating the impact on hepatitis A incidence of the Israeli toddlers-only universal routine two-dose vaccination programme against hepatitis A initiated in 1999. All hepatitis A episodes reported to the national surveillance system from 1993 to 2012 were analysed in relation to the vaccination programme and coverage. Mean vaccine coverage in Israel between 2003 and 2010 was 92% for the first dose, given at 18 months of age, and 88% for the second dose, given at 24 months. The annual hepatitis A incidence declined from a mean of 50.4 per 100,000 in the period between 1993 and 1998 to a mean of?<1.0, during the period from 2008 to 2012, representing a reduction of?>98%. The decline was evident in all ages and ethnicity groups, including unvaccinated populations. Of the 1,247 cases reported nationwide between 2002 and 2012, the vaccination status could be ascertained in 1,108 (89%). Among them, only 20 (2%) were reported be vaccinated with one dose and three (<1%) received two doses. The sustained results of this long-term impact study suggest that a toddlers-only universal routine two-dose vaccination programme is highly effective and practical. These findings underscore the importance of sustainability in both the surveillance systems and vaccination programmes and will aid to determine vaccination policies.
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Affiliation(s)
- H Levine
- Braun School of Public Health and Community Medicine, Hebrew University-Hadassah, Jerusalem, Israel
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Deneke MG, Arguedas MR. Hepatitis A and considerations regarding the cost-effectiveness of vaccination programs. Expert Rev Vaccines 2014; 2:661-72. [PMID: 14711327 DOI: 10.1586/14760584.2.5.661] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hepatitis A vaccines have demonstrated a high degree of immunogenicity and an excellent safety profile. Immunization of certain populations and patient subgroups is recommended according to specific epidemiological and clinical factors, such as a greater likelihood of acquisition of infection or concerns regarding the risk of development of fulminant hepatitis and death. Therefore, the economic implications of routine and/or targeted vaccination programs in the general population and high-risk individuals have been examined. In this manuscript, the available data from the literature regarding the cost-effectiveness of hepatitis vaccination programs in healthy individuals and in those with chronic liver disease are reviewed.
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Affiliation(s)
- Matthew G Deneke
- Department of Internal Medicine University Of Alabama at Birmingham, Birmingham, AL 35294, USA
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Suwantika AA, Yegenoglu S, Riewpaiboon A, Tu HAT, Postma MJ. Economic evaluations of hepatitis A vaccination in middle-income countries. Expert Rev Vaccines 2013; 12:1479-94. [PMID: 24168129 DOI: 10.1586/14760584.2013.851008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Economic evaluations of hepatitis A vaccination are important to assist national and international policy makers in different jurisdictions on making effective decisions. Up to now, a comprehensive review of the potential health and economic benefits on hepatitis A vaccination in middle-income countries (MICs) has not been performed yet. In this study, we reviewed the literature on the cost-effectiveness of hepatitis A vaccination in MICs. Most of the studies confirmed that hepatitis A vaccination was cost effective or even cost saving under certain conditions. We found that vaccine price, medical costs, incidence and discount rate were the most influential parameters on the sensitivity analyses. Vaccine price has been shown as a barrier for MICs in implementing universal vaccination of hepatitis A. Given their relatively limited financial resources, implementation of single-dose vaccination could be considered. Despite our findings, we argue that further economic evaluations in MICs are still required in the near future.
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Affiliation(s)
- Auliya A Suwantika
- Unit of PharmacoEpidemiology & PharmacoEconomics (PE2), Department of Pharmacy, University of Groningen, Groningen, The Netherlands
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Suijkerbuijk A, Lugnér A, van Pelt W, Wallinga J, Verhoef L, de Melker H, de Wit G. Assessing potential introduction of universal or targeted hepatitis A vaccination in the Netherlands. Vaccine 2012; 30:5199-205. [DOI: 10.1016/j.vaccine.2012.06.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 05/21/2012] [Accepted: 06/05/2012] [Indexed: 11/27/2022]
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De Soárez PC, Sartori AMC, Santos A, Itria A, Novaes HMD, Martelli CMT. Contributions from the systematic review of economic evaluations: the case of childhood hepatitis A vaccination in Brazil. CAD SAUDE PUBLICA 2012; 28:211-28. [DOI: 10.1590/s0102-311x2012000200002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 11/21/2011] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to present the contributions of the systematic review of economic evaluations to the development of a national study on childhood hepatitis A vaccination. A literature review was performed in EMBASE, MEDLINE, WOPEC, HealthSTAR, SciELO and LILACS from 1995 to 2010. Most of the studies (8 of 10) showed favorable cost-effectiveness results. Sensitivity analysis indicated that the most important parameters for the results were cost of the vaccine, hepatitis A incidence, and medical costs of the disease. Variability was observed in methodological characteristics and estimates of key variables among the 10 studies reviewed. It is not possible to generalize results or transfer epidemiological estimates of resource utilization and costs associated with hepatitis A to the local context. Systematic review of economic evaluation studies of hepatitis A vaccine demonstrated the need for a national analysis and provided input for the development of a new decision-making model for Brazil.
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Chodick G, Waisbourd-Zinman O, Shalev V, Kokia E, Rabinovich M, Ashkenazi S. Potential impact and cost-effectiveness analysis of rotavirus vaccination of children in Israel. Eur J Public Health 2009; 19:254-9. [DOI: 10.1093/eurpub/ckp005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Fisenka EG, Germanovich FA, Glinskaya IN, Lyabis OI, Rasuli AM. Effectiveness of universal hepatitis A immunization of children in Minsk City, Belarus: four-year follow-up. J Viral Hepat 2008; 15 Suppl 2:57-61. [PMID: 18837836 DOI: 10.1111/j.1365-2893.2008.01031.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Hepatitis A is a reportable disease in Belarus. Universal hepatitis A vaccination of children aged 6 years in Minsk City began in 2003. This analysis was conducted to evaluate the short-term impact of the program. Hepatitis A incidence data from 1954 to 2006 was compiled. Vaccination effectiveness was estimated by comparing the incidence of reported hepatitis A cases after 4 years of immunization (2006) with the incidence when the vaccination program started (2003). The vaccines used were Avaxim 160 or Avaxim 80 (95%) and Havrix 720 (5%). From 2003 through 2006, hepatitis A incidence in vaccinated children under 14 years was 20-fold lower than the incidence in unvaccinated children (0.3 cases/10000 vs 5.98/10000; odds ratio = 0.05, 95% CI: 0.012-0.202), for a vaccination effectiveness of 95%. The decreased incidence of hepatitis A in all age groups in 2006 (by 12 times in preschool children aged 1-5 years, 13 times in children aged 10-14 years and 4-6 times among adults), including those without high coverage by vaccination, suggest a herd effect. Routine vaccination also resulted in a shift of the age pattern of hepatitis A morbidity. The proportion of cases in children under 14 years decreased from 33% to 41% in 2000-2002 to 7% in 2005-2006. We conclude that introduction of universal hepatitis A vaccination in Minsk resulted in sharply reduced incidence in both vaccinated and unvaccinated children. Hepatitis A virus circulation might decrease further by beginning vaccination at a younger age.
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Affiliation(s)
- E G Fisenka
- Municipal Center of Hygiene and Epidemiology, Minsk, Belarus.
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Zhuang GH, Pan XJ, Wang XL. A cost-effectiveness analysis of universal childhood hepatitis A vaccination in China. Vaccine 2008; 26:4608-16. [DOI: 10.1016/j.vaccine.2008.05.086] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Revised: 05/03/2008] [Accepted: 05/19/2008] [Indexed: 11/16/2022]
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Lafer MM, de Moraes-Pinto MI, Weckx LY. Prevalence of antibodies against hepatitis A virus among the Kuikuro and Kaiabi Indians of Xingu National Park, Brazil. Rev Inst Med Trop Sao Paulo 2007; 49:155-7. [PMID: 17625692 DOI: 10.1590/s0036-46652007000300004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Accepted: 10/16/2006] [Indexed: 11/21/2022] Open
Abstract
A seroprevalence study to detect total antibodies against Hepatitis A Virus was done with 220 samples from 589 Native Indians from Xingu National Park, Brazil, in five Kaiabi and Kuikuro villages, the most populous ethnic groups. Using a commercial immunoassay kit we detected 97.7% positive samples (95% Confidence Interval: 95%-99%). We noticed a precocious seroconversion, before the age of six years, when the disease is usually asymptomatic. These results are similar to those found in the literature in non-Indian population studies of the Northern, Northeastern and West Central regions of Brazil. They suggest that it is not necessary to introduce vaccination against Hepatitis A in these highly endemic populations.
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Affiliation(s)
- Manuel Mindlin Lafer
- Division of Pediatric Infectious Diseases, Federal University of São Paulo (UNIFESP-EPM), SP/Brazil.
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Stein-Zamir C, Volovik I, Rishpon S. Control of Hepatitis A outbreaks in an endemic community: the role of sustained immunization coverage. Public Health 2007; 121:199-201. [PMID: 17250859 DOI: 10.1016/j.puhe.2006.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Revised: 06/09/2006] [Accepted: 08/02/2006] [Indexed: 10/23/2022]
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Lopez E, Debbag R, Coudeville L, Baron-Papillon F, Armoni J. The cost-effectiveness of universal vaccination of children against hepatitis A in Argentina: results of a dynamic health-economic analysis. J Gastroenterol 2007; 42:152-60. [PMID: 17351805 DOI: 10.1007/s00535-006-1984-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Accepted: 11/24/2006] [Indexed: 02/04/2023]
Abstract
BACKGROUND Socioeconomic improvements can reduce levels of endemic hepatitis A, but conversely increase the burden of disease. Routine childhood vaccination can rapidly control hepatitis A infection rates through the induction of herd immunity, although such programs can be costly. METHODS We evaluated the healthcare benefits and cost-effectiveness of a routine childhood vaccination program against hepatitis A in Argentina, using a dynamic model that incorporated the changing epidemiology of infection and the impact of vaccine-induced herd immunity. Demographic, disease, and economic data from Argentina were used where available. RESULTS At 95% coverage, the program would reduce the number of hepatitis A infections by 352,405 annually, avoiding 121,587 symptomatic cases and 428 deaths. Substantial healthcare benefits were also observed with vaccination coverage as low as 70%, which would prevent 295,826 infections. Economically, the program would save 23,989,963 US$ annually at 95% coverage, equivalent to 3,429 US$ per life-year gained. The program remained cost-saving in response to variation in factors, including disease-related costs, discount rate, herd immunity level, and rate of decrease of force of infection. The break-even cost per vaccine dose for the society was 25 US$ in the base-case, more than three times the current public cost of 7 US$ per dose. CONCLUSIONS Routine childhood vaccination against hepatitis A showed both health benefits and robust economic benefits in this analysis, supporting the recent decision of the Argentine government to implement such a program.
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Abstract
When first introduced in 1992 the hepatitis A vaccine was recommended for individuals at high risk of exposure. This policy was not expected to have a significant impact on disease incidence at population level in view of the epidemiology of the hepatitis A virus (HAV). More recently two countries, Israel and Bahrain, and regions or subpopulations in others (Australia, China, Byelorussia, Italy, Spain, US) have embarked upon more ambitious vaccination programmes that aim to immunize whole birth cohorts. After a brief survey of the virology and epidemiology of HAV, the disease burden it inflicts and a short history of the development of HAV vaccines--both live (in China) and killed vaccines are available--he vaccination programmes introduced in the countries mentioned above are described. The results have been spectacular: disease incidence, not only in the vaccinated cohorts but also in the whole population, have plummeted within a few years of the start of mass vaccination. There is now convincing evidence that the vaccine confers herd immunity if the main spreaders of the virus are targeted for immunization. This finding should encourage other countries to start mass vaccination programmes against HAV, particularly as pharmacoeconomic studies are beginning to show that such a strategy could be a cost-effective way of controlling the disease. It is now even conceivable to eradicate HAV. In fact, this should be easier to achieve than polio eradication as HAV vaccines confer more durable immunity than polio vaccines. However, the global disease burden of HAV is generally thought not to be high enough to justify such an undertaking in the foreseeable future.
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Abstract
Prevention of viral hepatitis infection involves health measures designed to avert transmission of viral agents and promote the use of gammaglobulin and vaccines. The availability of safe drinking water and improvements in quality of life result in better individual hygiene; these factors have had the greatest impact on hepatitis A prevention. Serum gammaglobulin administration has been replaced by vaccinations for pre-exposure, and to a great extent for post-exposure prophylaxis because of the progressively lower anti-HAV content of gammaglobulin and the short duration of the protective effect. Universal vaccination in childhood is the recommended measure for controlling hepatitis A. Adults belonging to high-risk groups should also undergo vaccination. The incidence of hepatitis B has decreased worldwide because of universal vaccination programs, initiated in preadolescence and childhood. Prevention of hepatitis C requires control of situations in which there is a likelihood of parenteral infection with the virus. Post-transfusion hepatitis has been virtually eradicated, but considerable effort is still needed to prevent nosocomial hepatitis.
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Affiliation(s)
- Miguel Bruguera
- Servicio de Hepatología, Hospital Clínic de Barcelona y Departamento de Medicina, Universidad de Barcelona, España.
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Affiliation(s)
- David B Rein
- Public Health Economics, RTI International, Atlanta, GA 30306, USA.
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Samuels N. Routine testing for IgG antibodies against hepatitis A virus in Israel. BMC Public Health 2005; 5:60. [PMID: 15935104 PMCID: PMC1173118 DOI: 10.1186/1471-2458-5-60] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Accepted: 06/06/2005] [Indexed: 11/20/2022] Open
Abstract
Background Viral hepatitis is highly endemic in Israel, with the hepatitis A virus (HAV) responsible for most cases. Improved socioeconomic factors, as well as the universal vaccination of infants (introduced in 1999) has resulted in a decline in infection rates in Israel. This study examines the benefits of routine testing for anti-HAV IgG in high-risk population. Methods A retrospective examination of the files of teenage and adult patients (aged 16–99 years; mean 33.9) in two primary care clinics found 1,017 patients who had been tested for anti-HAV IgG antibodies for either general healthcare screening or ongoing follow-up for chronic illness. Seropositive patients were then asked regarding recall of past hepatitis (i.e. jaundice, regardless of viral etiology); post-exposure prophylaxis with immune serum immunoglobulin (ISG); and active immunization with inactivated virus. Seronegative patients were subsequently sent for active immunization. Results Of the1,017 patient records studied (503 male, 514 female), a total of 692 were seropositive (354 males, 338 females; P = 0.113). Seropositivity rates increased with age (p < 0.005), and were highest among those born in Middle Eastern countries other than Israel (91.3%) and lowest among immigrants from South America (44.1%; P < 0.005). 456 of the seropositive patients were interviewed, of whom only 91 recalled past illness while 103 remembered receiving post-exposure prophylaxis (ISG) and 8 active vaccination. Those who were unaware of past infection were more likely to have been vaccinated with ISG than those who were aware (26.3% vs. 7.7%; p < 0.005). Conclusion The relatively high prevalence rate of anti-HAV seropositivity in our study may me due to the fact that the study was conducted in a primary care clinic or that it took place in Jerusalem, a relatively poor and densely populated Israeli city. Most of the seropostive patients had no recollection of prior infection, which can be explained by the fact that most hepatitis A infections occur during childhood and are asymptomatic. Routine testing for anti-HAV IgG in societies endemic for HAV would help prevent seropositive patients from receiving either post-exposure or preventive immunization and target seronegative patients for preventive vaccination.
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Affiliation(s)
- Noah Samuels
- Maccabi Healthcare Services, 130 Rachmilevich Street, Jerusalem 97791, Israel.
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Valenzuela MT, Jacobs RJ, Arteaga O, Navarrete MS, Meyerhoff AS, Innis BL. Cost-effectiveness of universal childhood hepatitis A vaccination in Chile. Vaccine 2005; 23:4110-9. [PMID: 15964479 DOI: 10.1016/j.vaccine.2005.03.021] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Revised: 03/18/2005] [Accepted: 03/24/2005] [Indexed: 11/17/2022]
Abstract
Hepatitis A is an important public health problem in Chile. Childhood vaccination has reduced hepatitis A rates in several countries, prompting this evaluation of its cost-effectiveness in Chile. Using a Markov model, we project mass vaccination would reduce hepatitis A cases among birth cohort members and their personal contacts >80%. Vaccination costs of US dollars 5.3-6.4 million would be offset by US dollars 9.2-9.4 million reductions in disease costs. Further, approximately 70 fatal infections would be averted and >4600 quality-adjusted life years would be saved. This analysis supports the cost-effectiveness of universal childhood hepatitis A vaccination in Chile.
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Affiliation(s)
- M Teresa Valenzuela
- School of Public Health, Faculty of Medicine, University of Chile, Santiago, Chile
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Ferreira CT, Silveira TRD. Hepatites virais: aspectos da epidemiologia e da prevenção. REVISTA BRASILEIRA DE EPIDEMIOLOGIA 2004. [DOI: 10.1590/s1415-790x2004000400010] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
As hepatites virais são doenças causadas por diferentes agentes etiológicos, de distribuição universal, que têm em comum o hepatotropismo. Possuem semelhanças do ponto de vista clínico-laboratorial, mas apresentam importantes diferenças epidemiológicas e quanto à sua evolução. As últimas décadas foram de notáveis conquistas no que se refere à prevenção e ao controle das hepatites virais. Entre as doenças endêmico-epidêmicas, que representam problemas importantes de saúde pública no Brasil, salientam-se as Hepatites Virais, cujo comportamento epidemiológico, no nosso país e no mundo, tem sofrido grandes mudanças nos últimos anos. A melhoria das condições de higiene e de saneamento das populações, a vacinação contra a Hepatite B e as novas técnicas moleculares de diagnóstico do vírus da Hepatite C estão entre esses avanços importantes. As condições do nosso país: sua heterogeneidade socioeconômica, a distribuição irregular dos serviços de saúde, a incorporação desigual de tecnologia avançada para diagnóstico e tratamento de enfermidades, são elementos importantes que devem ser considerados na avaliação do processo endemo-epidêmico das hepatites virais. O números de pacientes infectados é incerto, relacionado geralmente a alguns Estados e municípios brasileiros, e o esclarecimento dos agentes causadores das hepatites, cuja identificação requer técnicas laboratoriais complexas de biologia molecular, é realizado de maneira insuficiente. Por outro lado, "a progressiva integração entre as instâncias gestoras dos programas de vigilância e controle das doenças com grupos de pesquisa e desses com os serviços" e a disponibilização de bancos de dados nacionais mais confiáveis apontam para novos e melhores caminhos. No presente artigo é feita uma revisão sucinta das hepatites A, B e C, as mais freqüentes no nosso país, assim como de sua epidemiologia e das estratégias preferenciais para a prevenção dessas doenças.
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Ferreira CT, Leite JC, Taniguchi A, Vieira SM, Pereira-Lima J, da Silveira TR. Immunogenicity and safety of an inactivated hepatitis A vaccine in children with Down syndrome. J Pediatr Gastroenterol Nutr 2004; 39:337-40. [PMID: 15448421 DOI: 10.1097/00005176-200410000-00007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
OBJECTIVES Hepatitis A vaccine has not been investigated in children with Down syndrome. The aim of this study was to evaluate immunogenicity and safety of an inactivated hepatitis A vaccine in noninstitutionalized children with Down syndrome and compare their responses to those of healthy control children. METHODS An open, prospective, controlled trial of 127 children ages 1 to 12 years, 63 with Down syndrome and 64 healthy control subjects, was conducted at a single hospital. Inactivated hepatitis A virus (HAV) vaccine containing 720 enzyme-linked immunosorbent assay units of alum-adsorbed HAV was administered intramuscularly in a two-dose schedule at 0 and 6 months. Seroconversion and anti-HAV titers were measured at months 1 and 7. RESULTS Seroconversion rates at month 1 were 92% and 94% and geometric mean titers (GMT) were 164.02 and 160.77 mIU/mL in the Down syndrome (DS) and control groups, respectively. At month 7, seroconversion rates were 100% in both groups, with GMT of 1,719.86 and 2,344.90 mIU/mL in the DS and control groups, respectively (P = 0.117). Both doses were well tolerated and no significant adverse events observed. Local reaction at the injection site was the most common adverse event reported in both groups (15% in DS and 11% in controls). CONCLUSIONS The authors' data demonstrate a good response to HAV vaccination in children with DS living at home, with GMT not statistically different from that of healthy control children. HAV vaccine is well tolerated and highly immunogenic in children with DS.
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Affiliation(s)
- Cristina Targa Ferreira
- Pediatric Gastroenterology, Hospital de Clínicas de Porto Alegre, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
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Chabot I, Goetghebeur MM, Grégoire JP. The societal value of universal childhood vaccination. Vaccine 2004; 22:1992-2005. [PMID: 15121312 DOI: 10.1016/j.vaccine.2003.10.027] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2003] [Revised: 10/19/2003] [Accepted: 10/21/2003] [Indexed: 11/17/2022]
Abstract
Availability of new vaccines preventing infectious diseases in healthy children populations is increasing worldwide. In Canada, despite the current recommendation of the National Advisory Committee on Immunization to include recent vaccines in routine schedule, only a few provinces have incorporated some of the newer vaccines in routine vaccination programs. A review was undertaken of economic evaluations of childhood vaccination strategies performed from the societal point of view in industrialized countries, to gain perspective on their global benefits. The general trend supports most universal vaccination programs as cost-saving or cost-effective for society. Comparison of vaccination programs with other health care interventions indicates that vaccines are often one of society's best healthcare investments. Current data suggest that the Canadian society would benefit from a more complete immunization program.
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Affiliation(s)
- Isabelle Chabot
- Department of Health Economics & Outcomes Research, Merck Frosst Canada Ltd., Kirkland, Que., Canada.
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Van Damme P, Banatvala J, Fay O, Iwarson S, McMahon B, Van Herck K, Shouval D, Bonanni P, Connor B, Cooksley G, Leroux-Roels G, Von Sonnenburg F. Hepatitis A booster vaccination: is there a need? Lancet 2003; 362:1065-71. [PMID: 14522539 DOI: 10.1016/s0140-6736(03)14418-2] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hepatitis A is one of the most common vaccine-preventable infectious diseases in the world. Effective vaccines against hepatitis A have been available since 1992, and they provide long-term immunity against the infection. However, there is no worldwide consensus on how long protection will last or whether there will be a need for hepatitis A virus (HAV) booster vaccinations in the future. In most countries, booster-vaccination policy is guided by manufacturers' recommendations, national authorities, or both. In June, 2002, a panel of international experts met to review the long-term immunogenicity and protection conferred by HAV vaccine in different population groups. Data have shown that after a full primary vaccination course, protective antibody amounts persist beyond 10 years in healthy individuals, and underlying immune memory provides protection far beyond the duration of anti-HAV antibodies. The group concluded that there is no evidence to lend support to HAV booster vaccination after a full primary vaccination course in a healthy individual. However, further investigations are needed before deciding if boosters can be omitted in special patient-groups.
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Affiliation(s)
- P Van Damme
- Centre for the Evaluation of Vaccination, WHO Collaborating Centre for Control and Prevention of Viral Hepatitis, Unit of Epidemiology and Social Medicine, University of Antwerp, 2610 , Antwerp, Belgium.
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Ferreira CT, da Silveira TR, Vieira SM, Taniguchi A, Pereira-Lima J. Immunogenicity and safety of hepatitis A vaccine in children with chronic liver disease. J Pediatr Gastroenterol Nutr 2003; 37:258-61. [PMID: 12960646 DOI: 10.1097/00005176-200309000-00011] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Acute hepatitis A superimposed on chronic liver disease has been associated with a more severe course of disease and development of fulminant hepatitis. The aim of this study was to evaluate the immunogenicity and safety of an inactivated hepatitis A virus vaccine in children with chronic liver disease. PATIENTS AND METHODS This was an open, prospective, and controlled trial with 89 anti-HAV negative children between 1 and 16 years of age studied at a pediatric liver disease and transplantation referral center. Inactivated HAV vaccine (Havrix), from GlaxoSmithKline Biologicals containing 720 Elisa units of alum-adsorbed hepatitis A antigen per 0.5 ml dose was used. Thirty-four pediatric patients with chronic liver disease (mean age: 7.0 +/- 4.86 years) and 55 healthy controls (mean age: 4.8 +/- 2.7 years) received two doses of Havrix vaccine in months zero and six. Seroconversion and anti-HAV titers expressed as geometric mean titers (GMT) in mIU/ml were measured at months one and seven, by a modified Hepatitis A virus antibodies (HAVAB) assay. RESULTS Seroconversion rates at four weeks after primary immunization were 76% and 94% and the GMT 107.77 and 160.77 mIU/ml in the patient and control groups, respectively. One month after second dose the seroconversion rates were 97% and 100% in the groups with GMT of 812.40 and 2,344.90 mIU/ml. Both doses were well tolerated with no significant adverse events observed. Local injection-site symptoms were the most common reactions reported in both groups. CONCLUSION Although GMTs were significantly lower in children with chronic liver disease compared to healthy controls, the overall seroconversion rates were not different. Hepatitis A virus vaccine was safe, well-tolerated, and immunogenic in children with chronic liver disease.
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Affiliation(s)
- Cristina Targa Ferreira
- Hospital de Clinicas and Universidade Federal do Rio Grande do Sul, School of Medicine, Porto Alegre, Brazil.
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26
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Abstract
STATEMENT OF PROBLEM Many healthcare decisions are difficult because they are complex and have important consequences such as the impact on survival or quality-of-life of individuals and on allocation of limited resources. The present state-of-the-art in healthcare decision modeling is often inadequate to properly assess these decisions. METHODS Based on a literature search and the experience of the authors, typical methodologies used in healthcare decision analysis modeling are explored and compared with methods used in other practices. An example of hormonal therapy decisions is used. RESULTS Useful methods that have been developed in other fields are presented. These include methods targeted toward appropriate assessment and representation of the complexity of decisions, assessment of uncertainty, use of nonexpected value decision analysis, and use of multi-attribute decision criteria. CONCLUSION The state-of-the-art in healthcare decision modeling can be improved through learning from other practices.
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Affiliation(s)
- Robert C Lee
- Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada.
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Abstract
Hepatitis A is a major public health problem in the United States and other developed countries, largely because decreased natural immunity allows for increased susceptibility. To evaluate the cost-effectiveness of routine vaccination of children, adolescents, and certain high-risk adults against hepatitis A, economic analyses of hepatitis A vaccination were identified through searches of MEDLINE, EMBASE, and BIOSIS (February, 1992, to December, 2001) for studies, reviews, editorials, and letters from peer-reviewed journals published in English, French, German, Italian, or Spanish. Experts were also contacted. Articles conforming to accepted standards of quality for health-economic studies were used to compile data on vaccination of children, and results were synthesized in a narrative review. This review of economic analyses of vaccine use in several developed countries shows cost-effectiveness comparable with that of other vaccines in children and within accepted boundaries for adolescents and high-risk adults.
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Affiliation(s)
- Philip Rosenthal
- Pediatric Liver Transplant Program, University of California, San Francisco, 94143, USA.
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Chodick G, Lerman Y, Wood F, Aloni H, Peled T, Ashkenazi S. Cost-utility analysis of hepatitis A prevention among health-care workers in Israel. J Occup Environ Med 2002; 44:109-15. [PMID: 11851212 DOI: 10.1097/00043764-200202000-00005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This study was conducted to evaluate the efficiency of different strategies of preventing hepatitis A (HA) among physicians, nurses, and paramedical staff by means of cost-effectiveness analysis. The strategies compared were passive immunization during a hepatitis A outbreak, systematic mass vaccination of all workers, and screening for antibodies to HA virus followed by vaccination of nonimmune employees. To predict the prevented number of HA cases, an epidemiological model was incorporated based on our previous nationwide study on clinical HA cases, seroepidemiological survey, and other scientific medical literature. Under the model assumptions, the lowest cost per prevented HA case ($6240) was achieved by screening prior vaccination among 18- to 39-year-old physicians and paramedical workers, and highest ($61,858) by mass vaccination of nurses over age 39 years. Because the price per prevented case may show that mass vaccination is highly cost-effective, especially among 18- to 39-year-old physicians and paramedical workers ($6399 and $8196, respectively), the cost per gained quality-adjusted life-year seems less attractive ($56,532 and $61,350, respectively). This cost per saved quality-adjusted life-year is similar to many other medical interventions but is markedly higher than other primary prevention vaccines, which are mostly associated with a negative ratio. In view of the conducted study, and taking $60,000 as a limit cost per saved quality-adjusted life-year, we propose selective vaccination for physicians and for paramedical workers. Mass vaccination should be offered to all health care workers, aside from nurses 40+ years of age, once the active HA vaccine price is reduced to $23.
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Affiliation(s)
- Gabriel Chodick
- Sackler Faculty of Medicine, Tel Aviv University, Department of Epidemiology & Preventive Medicine, POB 39040 Ramat-Aviv, Tel Aviv 69978, Israel.
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Poovorawan Y, Chatchatee P, Chongsrisawat V. Epidemiology and prophylaxis of viral hepatitis: a global perspective. J Gastroenterol Hepatol 2002; 17 Suppl:S155-66. [PMID: 12000601 DOI: 10.1046/j.1440-1746.17.s1.4.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Viral hepatitis with various forms of acute and chronic liver disease as potential and ultimately fatal sequelae presents a public health problem worldwide. METHODS Recent published reports on the global epidemiology and prophylaxis of viral hepatitis were reviewed. RESULTS With the advances in novel technologies, eight distinct types of hepatitis virus have been described: Hepatitis A, B, C, D, E, G, TT and SEN viruses. Hepatitis A and E viruses are transmitted by the fecal-oral route and do not induce a chronic carrier state. Due to major changes in epidemiology of hepatitis A virus their significance is more pronounced in areas of intermediate endemicity. Since the available hepatitis A vaccine is rather expensive, cost-benefit studies should be performed with emphasis on the area under consideration or specialized vulnerable groups. Parenterally transmitted hepatitis B and C viruses are major causes of chronic liver disease, including cirrhosis, hepatocellular carcinoma and end-stage liver failure. Hepatitis D virus is unable to replicate on its own, it requires an established hepatitis B virus infection to be able to replicate. Since its introduction, hepatitis B vaccine has been widely used leading to a significant decrease in HBV infection in countries with universal vaccination. Hepatitis G and TT viruses have been characterized within the latter part of the past decade but their significance as to the causation of human liver disease has yet to be elucidated. Likewise, the precise impact of the most recently described SEN virus isolated from patients with post-transfusion hepatitis awaits further studies. CONCLUSIONS In the course of this review, we present the situation and focus on research activities emphasizing epidemiology and prevention of the various forms of viral hepatitis.
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Affiliation(s)
- Yong Poovorawan
- Viral Hepatitis Research Unit, Department of Pediatrics, Chulalongkorn University and Hospital, Bangkok, Thailand.
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Beutels P, Edmunds WJ, Antoñanzas F, De Wit GA, Evans D, Feilden R, Fendrick AM, Ginsberg GM, Glick HA, Mast E, Péchevis M, Van Doorslaer EKA, van Hout BA. Economic evaluation of vaccination programmes: a consensus statement focusing on viral hepatitis. PHARMACOECONOMICS 2002; 20:1-7. [PMID: 11817988 DOI: 10.2165/00019053-200220010-00001] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The methods that have been used to estimate the clinical and economic impact of vaccination programmes are not always uniform, which makes it difficult to compare results between economic analyses. Furthermore, the relative efficiency of vaccination programmes can be sensitive to some of the more controversial aspects covered by general guidelines for the economic evaluation of healthcare programmes, such as discounting of health gains and the treatment of future unrelated costs. In view of this, we interpret some aspects of these guidelines with respect to vaccination and offer recommendations for future analyses. These recommendations include more transparency and validation, more careful choice of models (tailored to the infection and the target groups), more extensive sensitivity analyses, and for all economic evaluations (also nonvaccine related) to be in better accordance with general guidelines. We use these recommendations to interpret the evidence provided by economic evaluation applied to viral hepatitis vaccination. We conclude that universal hepatitis B vaccination (of neonates, infants or adolescents) seems to be the most optimal strategy worldwide, except in the few areas of very low endemicity, where the evidence to enable a choice between selective and universal vaccination remains inconclusive. While targeted hepatitis A vaccination seems economically unattractive, universal hepatitis A vaccination strategies have not yet been sufficiently investigated to draw general conclusions.
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Bruguera M. Vacuna de la hepatitis A en el control de los casos secundarios de hepatitis A. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1576-9887(02)70266-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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